Publications by category
Journal articles
Lange I, Perry C (In Press). A quick, easy and non-invasive method to quantify coral growth rates using photogrammetry 1 and 3D model comparisons.
Methods in Ecology and EvolutionAbstract:
A quick, easy and non-invasive method to quantify coral growth rates using photogrammetry 1 and 3D model comparisons
1. Coral growth rates vary significantly with environmental conditions and are thus important indicators of coral health and reef carbonate production. Despite the importance of this metric, data are sparse for most coral genera and species globally, including for many key reef-building species. Traditional methods to obtain growth rates, such as coral coring or staining with Alizarin are destructive and only work for a limited number of species and morphological growth forms.
2. Emerging approaches, using underwater photogrammetry to create digital models of coral colonies, are providing novel and non-invasive ways to explore colony-scale growth patterns and to address existing knowledge gaps. We developed an easy-to-follow workflow to construct 3D models from overlapping photographs and to measure linear, radial and vertical extension rates of branching, massive and encrusting corals after aligning colony models from subsequent years.
3. The method presented here was applied to measure extension rates for 47 colonies of nine coral species in the remote Chagos Archipelago, Indian Ocean. Proposed image acquisition and software settings produced 3D models of consistently high resolution and detail (precision ≤0.2 mm) and variability in growth measurements was small despite manual alignment, clipping and ruler placement (standard deviation ≤0.9 mm). Measured extension rates for the Chagos Archipelago are similar to published rates in the Indo-Pacific where comparable data is available, and provide the first published rates for several species. For encrusting corals, the results emphasize the importance of differentiating between radial and vertical growth.
4. Photogrammetry and 3D model comparisons provide a fast, easy, inexpensive and non-invasive method to quantify coral growth rates for a range of species and morphological growth forms. The simplicity of the presented workflow encourages its repeatability and permits non-specialists to learn photogrammetry with the goal of obtaining coral growth rates. Coral growth rates are essential metrics to quantify functional consequences of ongoing community changes on coral reefs and expanded datasets for key coral taxa will aid predictions of geographic variations in coral reef response to increasing global stressors.
Abstract.
Lange I, Perry CT (In Press). Bleaching impacts on carbonate production in the Chagos Archipelago: influence of functional coral groups on carbonate budget trajectories. Coral Reefs
Salter M, Perry C (In Press). Calcium carbonate production by fish in temperate marine environments. Limnology and Oceanography, 1-42.
Lange ID, Perry CT, Alvarez-Filip L (In Press). Carbonate budgets as indicators of functional reef “health”: a critical review of data underpinning census-based methods and current knowledge gaps. Ecological Indicators
Perry C, Murphy GN, Kench PS, Smithers SG, Edinger EN, Steneck RS, Mumby PJ (In Press). Caribbean-wide decline in carbonate production threatens coral reef growth. Nature Communications(4).
Perry C, Salter M, Morgan K, Harborne A (In Press). Census estimates of algal and epiphytic carbonate production highlight tropical seagrass meadows as sediment production hotspots. Frontiers in Marine Science
East H, Perry C, Kench P, Liang Y, Gulliver P (In Press). Coral Reef Island Initiation and Development Under Higher Than Present Sea Levels. Geophysical Research Letters
Molina-Hernández A, Medellín-Maldonado F, Lange I, Perry C, Alvarez-Filip L (In Press). Coral reef erosion: in situ measurement on different dead coral substrates on a Caribbean reef. Limnology and Oceanography
Husband E, Perry CT, Lange ID (In Press). Estimating rates of coral carbonate production from aerial
3 and archive imagery by applying colony scale conversion metrics. Coral Reefs
de Bakker D, van Duyl FC, Perry CT, Meesters EH (In Press). Extreme spatial heterogeneity in carbonate accretion potential on a Caribbean fringing reef linked to local human disturbance gradients. Global Change Biology
Estrada-Saldivar N, Jordan-Dalhgren E, Rodriguez-Martinez R, Perry CT, Alvarez-Filip L (In Press). Functional consequences of the long-term decline of reef-building corals in the Caribbean: evidence of across-reef functional convergence. Royal Society Open Science
Perry C (In Press). Geo-ecological functions provided by coral reef fishes vary among regions and impact reef carbonate cycling regimes. Ecosphere
Perry C, Smithers SG, Kench PS, Pears B (In Press). Impacts of Severe Tropical Cyclone Yasi on nearshore, terrigenous sediment-dominated reefs of the central Great Barrier Reef, Australia. Geomorphology, 222, 92-105.
Perry C, Kench PS, O'Leary MJ, Morgan KM, Januchowski-Hartle F (In Press). Linking reef ecology to island-building: Parrotfish identified as major producers of island-building sediment in the Maldives. Geology (Boulder), 43, 503-506.
Morgan KM, Perry CT, Johnson J, Smithers SG (In Press). Nearshore turbid-zone corals exhibit high bleaching tolerance on the Great Barrier Reef following the 2016 ocean warming event. Frontiers in Marine Science
Johnson J, Perry CT, Smithers SG, Morgan KM, Santodomingo N, Johnson K (In Press). Palaeoecological records of coral community development
on a turbid, nearshore reef complex: baselines for assessing
ecological change. Coral Reefs
Salter MA, Harborne AR, Perry CT, Wilson RW (In Press). Phase heterogeneity in carbonate production by marine fish influences their roles in sediment generation and the inorganic carbon cycle. Scientific Reports
Perry C (In Press). Post-bleaching coral community change on southern Maldivian reefs: is there potential for rapid recovery?. Coral Reefs
Yarlett R, Perry C, Wilson RW (In Press). Quantifying production rates and size fractions of parrotfish-derived sediment: a key functional role on Maldivian coral reefs. Ecology and Evolution
Salter MA, Perry CT, Stuart-Smith R, Edgar GJ, Wilson RW, Harborne AR (In Press). Reef fish carbonate production assessments highlight regional variation in sedimentary significance. Geology
Perry C, Morgan K, Yarlett R (In Press). Reef habitat type and spatial extent as interacting controls on platform-scale carbonate budgets. Frontiers in Marine Science
Johnson J, Perry CT, Smithers SG, Morgan KM, Woodroffe SA (In Press). Reef shallowing is a critical driver of benthic foraminiferal assemblage composition on nearshore turbid-zone coral reefs. Palaeogeography, Palaeoclimatology, Palaeoecology
Perry C, Murphy G, Graham NAJ, Wilson SK, Januchowski-Hartley F, East H (In Press). Remote coral reefs can sustain high growth potential and may match future sea-level trends. Scientific Reports
Perry C (In Press). Seagrass meadows are important sources of reef island-building sediment. Communications Earth & Environment
Perry C, Morgan KM, Salter MA (In Press). Sediment generation by Halimeda on atoll interior coral reefs of the southern Maldives: a census-based approach for estimating carbonate production by calcareous green algae. Sedimentary Geology
Molina-Hernández A, González-Barrios F, Perry C, Alvarez-Filip L (In Press). Two decades of carbonate budget change on shifted coral reef assemblages: are these reefs being locked into low net budget states?. Proceeedings of the Royal Society: B
Ghilardi M, Salter MA, Parravicini V, Ferse SCA, Rixen T, Wild C, Birkicht M, Perry CT, Berry A, Wilson RW, et al (2023). Temperature, species identity and morphological traits predict carbonate excretion and mineralogy in tropical reef fishes.
Nature Communications,
14(1).
Abstract:
Temperature, species identity and morphological traits predict carbonate excretion and mineralogy in tropical reef fishes
AbstractAnthropogenic pressures are restructuring coral reefs globally. Sound predictions of the expected changes in key reef functions require adequate knowledge of their drivers. Here we investigate the determinants of a poorly-studied yet relevant biogeochemical function sustained by marine bony fishes: the excretion of intestinal carbonates. Compiling carbonate excretion rates and mineralogical composition from 382 individual coral reef fishes (85 species and 35 families), we identify the environmental factors and fish traits that predict them. We find that body mass and relative intestinal length (RIL) are the strongest predictors of carbonate excretion. Larger fishes and those with longer intestines excrete disproportionately less carbonate per unit mass than smaller fishes and those with shorter intestines. The mineralogical composition of excreted carbonates is highly conserved within families, but also controlled by RIL and temperature. These results fundamentally advance our understanding of the role of fishes in inorganic carbon cycling and how this contribution will change as community composition shifts under increasing anthropogenic pressures.
Abstract.
Lange I, Perry C, Stuhr M (2022). Recovery trends of reef carbonate budgets at remote coral atolls 6 years post-bleaching.
Limnology and OceanographyAbstract:
Recovery trends of reef carbonate budgets at remote coral atolls 6 years post-bleaching
Coral bleaching events and resultant changes in benthic community composition and population size structure can diminish the important geo-ecological functions reefs provide, including habitat provision and carbonate production to support reef accretion. Net reef carbonate budgets, the balance between carbonate production and erosion processes, are thus important functional indicators of reef health. This study quantifies changes in coral community composition and colony size structures, and the resultant reef carbonate budget trajectories after the 2015/2016 bleaching event in the remote Chagos Archipelago, Indian Ocean. ReefBudget surveys were conducted at 12 sites across three atolls in 2015, 2018 and 2021, with calculations of biological carbonate production and erosion supported by locally obtained calcification and bioerosion rates. Carbonate budgets (in G = kg CaCO3 m-2 yr-1) shifted from net positive states in 2015 (mean±SD: 3.8±2.6 G) to net negative states in 2018 (-2.4±1.4 G) in response to bleaching-driven mass coral mortality. By 2021, all sites were on a trajectory of recovery, but net budgets differed significantly between atolls (-2.0±1.7 to 2.2±1.4 G). At Salomon atoll, the 3-fold faster recovery of carbonate production and return to positive reef budget states only six years post-bleaching was associated with the persistence of high structural complexity and the rapid recovery of fast growing tabular Acropora spp. Inter-atoll differences in colony size distributions furthermore illustrate that coral identity and size class are more important predictors of reef functions and post-disturbance recovery speed than coral cover alone.
Abstract.
Lange ID, Molina-Hernández A, Medellín-Maldonado F, Perry CT, Álvarez-Filip L (2022). Structure-from-motion photogrammetry demonstrates variability in coral growth within colonies and across habitats.
PLOS ONE,
17(11), e0277546-e0277546.
Abstract:
Structure-from-motion photogrammetry demonstrates variability in coral growth within colonies and across habitats
Coral growth is an important metric of coral health and underpins reef-scale functional attributes such as structural complexity and calcium carbonate production. There persists, however, a paucity of growth data for most reef-building regions, especially for coral species whose skeletal architecture prevents the use of traditional methods such as coring and Alizarin staining. We used structure-from-motion photogrammetry to quantify a range of colony-scale growth metrics for six coral species in the Mexican Caribbean and present a newly developed workflow to measure colony volume change over time. Our results provide the first growth metrics for two species that are now major space occupiers on Caribbean reefs, Agaricia agaricites and Agaricia tenuifolia. We also document higher linear extension, volume increase and calcification rates within back reef compared to fore reef environments for four other common species: Orbicella faveolata, Porites astreoides, Siderastrea siderea and Pseudodiploria strigosa. Linear extension rates in our study were lower than those obtained via computed tomography (CT) scans of coral cores from the same sites, as the photogrammetry method averages growth in all dimensions, while the CT method depicts growth only along the main growth axis (upwards). The comparison of direct volume change versus potential volume increase calculated from linear extension emphasizes the importance of assessing whole colony growth to improve calcification estimates. The method presented here provides an approach that can generate accurate calcification estimates alongside a range of other whole-colony growth metrics in a non-invasive way.
Abstract.
Cornwall CE, Comeau S, Kornder NA, Perry CT, van Hooidonk R, DeCarlo TM, Pratchett MS, Anderson KD, Browne N, Carpenter R, et al (2021). Global declines in coral reef calcium carbonate production under ocean acidification and warming.
Proceedings of the National Academy of Sciences,
118(21).
Abstract:
Global declines in coral reef calcium carbonate production under ocean acidification and warming
Significance
. The growth of coral reefs is threatened by the dual stressors of ocean warming and acidification. Despite a wealth of studies assessing the impacts of climate change on individual taxa, projections of their impacts on coral reef net carbonate production are limited. By projecting impacts across 233 different locations, we demonstrate that the majority of coral reefs will be unable to maintain positive net carbonate production globally by the year 2100 under representative concentration pathways RCP4.5 and 8.5, while even under RCP2.6, coral reefs will suffer reduced accretion rates. Our results provide quantitative projections of how different climate change stressors will influence whole ecosystem carbonate production across coral reefs in all major ocean basins.
Abstract.
Pereira-Filho GH, Mendes VR, Perry CT, Shintate GI, Niz WC, Sawakuchi AO, Bastos AC, Giannini PCF, Motta FS, Millo C, et al (2021). Growing at the limit: Reef growth sensitivity to climate and oceanographic changes in the South Western Atlantic. Global and Planetary Change, 201, 103479-103479.
Duvat VKE, Magnan AK, Perry CT, Spencer T, Bell JD, Wabnitz CCC, Webb AP, White I, McInnes KL, Gattuso JP, et al (2021). Risks to future atoll habitability from climate-driven environmental changes.
Wiley Interdisciplinary Reviews: Climate Change,
12(3).
Abstract:
Risks to future atoll habitability from climate-driven environmental changes
Recent assessments of future risk to atoll habitability have focused on island erosion and submergence, and have overlooked the effects of other climate-related drivers, as well as differences between ocean basins and island types. Here we investigate the cumulative risk arising from multiple drivers (sea-level rise; changes in rainfall, ocean–atmosphere oscillations and tropical cyclone intensity; ocean warming and acidification) to five Habitability Pillars: Land, Freshwater supply, Food supply, Settlements and infrastructure, and Economic activities. Risk is assessed for urban and rural islands of the Pacific and Indian Oceans, under RCP2.6 and RCP8.5, in 2050 and 2090, and considering a moderate adaptation scenario. Risks will be highest in the Western Pacific which will experience increased island destabilization together with a high threat to freshwater, and decreased land-based and marine food supply from reef-dependent fish and tuna and tuna-like resources. Risk accumulation will occur at a lower rate in the Central Pacific (lower pressure on land, with more limited cascading effects on other Habitability Pillars; increase in pelagic fish stocks) and the Central Indian Ocean (mostly experiencing increased land destabilization and reef degradation). Risk levels will vary significantly between urban islands, depending on geomorphology and local shoreline disturbances. Rural islands will experience less contrasting risk levels, but higher risks than urban islands in the second half of the century. This article is categorized under: Trans-Disciplinary Perspectives > Regional Reviews.
Abstract.
McWhorter JK, Halloran PR, Roff G, Skirving WJ, Perry CT, Mumby PJ (2021). The importance of 1.5°C warming for the Great Barrier Reef. Global Change Biology, 28(4), 1332-1341.
Lange ID, Benkwitt CE, McDevitt-Irwin JM, Tietjen KL, Taylor B, Chinkin M, Gunn RL, Palmisciano M, Steyaert M, Wilson B, et al (2021). Wave exposure shapes reef community composition and recovery trajectories at a remote coral atoll.
Coral Reefs,
40(6), 1819-1829.
Abstract:
Wave exposure shapes reef community composition and recovery trajectories at a remote coral atoll
AbstractIn a time of unprecedented ecological change, understanding natural biophysical relationships between reef resilience and physical drivers is of increasing importance. This study evaluates how wave forcing structures coral reef benthic community composition and recovery trajectories after the major 2015/2016 bleaching event in the remote Chagos Archipelago, Indian Ocean. Benthic cover and substrate rugosity were quantified from digital imagery at 23 fore reef sites around a small coral atoll (Salomon) in 2020 and compared to data from a similar survey in 2006 and opportunistic surveys in intermediate years. Cluster analysis and principal component analysis show strong separation of community composition between exposed (modelled wave exposure > 1000 J m−3) and sheltered sites (< 1000 J m−3) in 2020. This difference is driven by relatively high cover of Porites sp. other massive corals, encrusting corals, soft corals, rubble and dead table corals at sheltered sites versus high cover of pavement and sponges at exposed sites. Total coral cover and rugosity were also higher at sheltered sites. Adding data from previous years shows benthic community shifts from distinct exposure-driven assemblages and high live coral cover in 2006 towards bare pavement, dead Acropora tables and rubble after the 2015/2016 bleaching event. The subsequent recovery trajectories at sheltered and exposed sites are surprisingly parallel and lead communities towards their respective pre-bleaching communities. These results demonstrate that in the absence of human stressors, community patterns on fore reefs are strongly controlled by wave exposure, even during and after widespread coral loss from bleaching events.
Abstract.
Hays GC, Koldewey HJ, Andrzejaczek S, Attrill MJ, Barley S, Bayley DTI, Benkwitt CE, Block B, Schallert RJ, Carlisle AB, et al (2020). A review of a decade of lessons from one of the world’s largest MPAs: conservation gains and key challenges. Marine Biology, 167(11).
Perry CT, Morgan KM, Lange ID, Yarlett RT (2020). Bleaching-driven reef community shifts drive pulses of increased reef sediment generation.
Royal Society Open Science,
7(4), 192153-192153.
Abstract:
Bleaching-driven reef community shifts drive pulses of increased reef sediment generation
. The ecological impacts of coral bleaching on reef communities are well documented, but resultant impacts upon reef-derived sediment supply are poorly quantified. This is an important knowledge gap because these biogenic sediments underpin shoreline and reef island maintenance. Here, we explore the impacts of the 2016 bleaching event on sediment generation by two dominant sediment producers (parrotfish and
. Halimeda
. spp.) on southern Maldivian reefs. Our data identifies two pulses of increased sediment generation in the 3 years since bleaching. The first occurred within approximately six months after bleaching as parrotfish biomass and resultant erosion rates increased, probably in response to enhanced food availability. The second pulse occurred 1 to 3 years post-bleaching, after further increases in parrotfish biomass and a major (approx. fourfold) increase in
. Halimeda
. spp. abundance. Total estimated sediment generation from these two producers increased from approximately 0.5 kg CaCO
. 3
. m
. −2
. yr
. −1
. (pre-bleaching; 2016) to approximately 3.7 kg CaCO
. 3
. m
. −2
. yr
. −1
. (post-bleaching; 2019), highlighting the strong links between reef ecology and sediment generation. However, the relevance of this sediment for shoreline maintenance probably diverges with each producer group, with parrotfish-derived sediment a more appropriate size fraction to potentially contribute to local island shorelines.
.
Abstract.
Hattam C, Evans L, Morrissey K, Hooper T, Young K, Khalid F, Bryant M, Thani A, Slade L, Perry C, et al (2020). Building resilience in practice to support coral communities in the Western Indian Ocean. Environmental Science & Policy, 106, 182-190.
Yarlett RT, Perry CT, Wilson RW, Harborne AR (2020). Inter-Habitat Variability in Parrotfish Bioerosion Rates and Grazing Pressure on an Indian Ocean Reef Platform.
Diversity,
12(10), 381-381.
Abstract:
Inter-Habitat Variability in Parrotfish Bioerosion Rates and Grazing Pressure on an Indian Ocean Reef Platform
Parrotfish perform a variety of vital ecological functions on coral reefs, but we have little understanding of how these vary spatially as a result of inter-habitat variability in species assemblages. Here, we examine how two key ecological functions that result from parrotfish feeding, bioerosion and substrate grazing, vary between habitats over a reef scale in the central Maldives. Eight distinct habitats were delineated in early 2015, prior to the 2016 bleaching event, each supporting a unique parrotfish assemblage. Bioerosion rates varied from 0 to 0.84 ± 0.12 kg m−2 yr−1 but were highest in the coral rubble- and Pocillopora spp.-dominated habitat. Grazing pressure also varied markedly between habitats but followed a different inter-habitat pattern from that of bioerosion, with different contributing species. Total parrotfish grazing pressure ranged from 0 to ~264 ± 16% available substrate grazed yr-1 in the branching Acropora spp.-dominated habitat. Despite the importance of these functions in influencing reef-scale physical structure and ecological health, the highest rates occurred over less than 30% of the platform area. The results presented here provide new insights into within-reef variability in parrotfish ecological functions and demonstrate the importance of considering how these interact to influence reef geo-ecology.
Abstract.
East HK, Perry CT, Beetham EP, Kench PS, Liang Y (2020). Modelling reef hydrodynamics and sediment mobility under sea level rise in atoll reef island systems. Global and Planetary Change, 192, 103196-103196.
Salter MA, Rodríguez-Martínez RE, Álvarez-Filip L, Jordán-Dahlgren E, Perry CT (2020). Pelagic Sargassum as an emerging vector of high rate carbonate sediment import to tropical Atlantic coastlines. Global and Planetary Change, 103332-103332.
Morgan KM, Perry CT, Arthur R, Williams HTP, Smithers SG (2020). Projections of coral cover and habitat change on turbid reefs under future sea-level rise.
Proceedings. Biological sciences,
287(1929), 20200541-20200541.
Abstract:
Projections of coral cover and habitat change on turbid reefs under future sea-level rise
Global sea-level rise (SLR) is projected to increase water depths above coral reefs. Although the impacts of climate disturbance events on coral cover and three-dimensional complexity are well documented, knowledge of how higher sea levels will influence future reef habitat extent and bioconstruction is limited. Here, we use 31 reef cores, coupled with detailed benthic ecological data, from turbid reefs on the central Great Barrier Reef, Australia, to model broad-scale changes in reef habitat following adjustments to reef geomorphology under different SLR scenarios. Model outputs show that modest increases in relative water depth above reefs (Representative Concentration Pathway (RCP) 4.5) over the next 100 years will increase the spatial extent of habitats with low coral cover and generic diversity. More severe SLR (RCP8.5) will completely submerge reef flats and move reef slope coral communities below the euphotic depth, despite the high vertical accretion rates that characterize these reefs. Our findings suggest adverse future trajectories associated with high emission climate scenarios which could threaten turbid reefs globally and their capacity to act as coral refugia from climate change.
Abstract.
Lange ID, Perry CT, Morgan KM, Roche R, Benkwitt CE, Graham NAJ (2020). Site-Level Variation in Parrotfish Grazing and Bioerosion as a Function of Species-Specific Feeding Metrics.
Diversity,
12(10), 379-379.
Abstract:
Site-Level Variation in Parrotfish Grazing and Bioerosion as a Function of Species-Specific Feeding Metrics
Parrotfish provide important ecological functions on coral reefs, including the provision of new settlement space through grazing and the generation of sediment through bioerosion of reef substrate. Estimating these functions at an ecosystem level depends on accurately quantifying the functional impact of individuals, yet parrotfish feeding metrics are only available for a limited range of sites, species and size classes. We quantified bite rates, proportion of bites leaving scars and scar sizes in situ for the dominant excavator (Cetoscarus ocellatus, Chlorurus strongylocephalus, Ch. sordidus) and scraper species (Scarus rubroviolaceus, S. frenatus, S. niger, S. tricolor, S. scaber, S. psittacus) in the central Indian Ocean. This includes the first record of scar frequencies and sizes for the latter three species. Bite rates varied with species and life phase and decreased with body size. The proportion of bites leaving scars and scar sizes differed among species and increased with body size. Species-level allometric relationships between body size and each of these feeding metrics were used to parameterize annual individual grazing and bioerosion rates which increase non-linearly with body size. Large individuals of C. ocellatus, Ch. strongylocephalus and S. rubroviolaceus can graze 200–400 m2 and erode >500 kg of reef substrate annually. Smaller species graze 1–100 m2 yr−1 and erode 0.2–30 kg yr−1. We used these individual functional rates to quantify community grazing and bioerosion levels at 15 sites across the Maldives and the Chagos Archipelago. Although parrotfish density was 2.6 times higher on Maldivian reefs, average grazing (3.9 ± 1.4 m2 m−2 reef yr−1) and bioerosion levels (3.1 ± 1.2 kg m−2 reef yr−1) were about 15% lower than in the Chagos Archipelago (4.5 ± 2.3 and 3.7 ± 3.0, respectively), due to the dominance of small species and individuals in the Maldives (90% <30 cm length). This demonstrates that large-bodied species and individuals contribute disproportionally to both grazing and bioerosion. Across all sites, grazing increased by 66 ± 5 m2 ha−1 and bioerosion by 109 ± 9 kg ha−1 for every kg increase in parrotfish biomass. However, for a given level of parrotfish biomass, grazing and bioerosion levels were higher on Maldivian reefs than in the Chagos Archipelago. This suggests that small-bodied fish assemblages can maintain ecosystem functions, but only if key species are present in sufficiently high numbers.
Abstract.
Winter G, Storlazzi C, Vitousek S, van Dongeren A, McCall R, Hoeke R, Skirving W, Marra J, Reyns J, Aucan J, et al (2020). Steps to Develop Early Warning Systems and Future Scenarios of Storm Wave-Driven Flooding Along Coral Reef-Lined Coasts. Frontiers in Marine Science, 7
Perry CT, Alvarez-Filip L (2019). Changing geo-ecological functions of coral reefs in the Anthropocene.
Functional Ecology,
33(6), 976-988.
Abstract:
Changing geo-ecological functions of coral reefs in the Anthropocene
The ecology of many coral reefs has changed markedly over recent decades in response to various combinations of local and global stressors. These ecological changes have important implications for the abundance of taxa that regulate the production and erosion of skeletal carbonates, and thus for many of the geo-ecological functions that coral reefs provide, including reef framework production and sediment generation, the maintenance of reef habitat complexity and reef growth potential. These functional attributes underpin many of the ecosystem goods and services that reefs provide to society. Rapidly changing conditions of reefs in the Anthropocene are likely to significantly impact the capacity of reefs to sustain these geo-ecological functions. Although the Anthropocene footprint of disturbance will be expressed differently across ecoregions and habitats, the end point for many reefs may be broadly similar: (a) progressively shifting towards net neutral or negative carbonate budget states; (b) becoming structurally flatter; and (c) having lower vertical growth rates. It is also likely that a progressive depth-homogenisation will occur in terms of these processes. The Anthropocene is likely to be defined by an increasing disconnect between the ecological processes that drive carbonate production on the reef surface, and the net geological outcome of that production, that is, the accumulation of the underlying reef structure. Reef structures are thus likely to become increasingly relict or senescent features, which will reduce reef habitat complexity and sediment generation rates, and limit reef potential to accrete vertically at rates that can track rising sea levels. In the absence of pervasive stressors, recovery of degraded coral communities has been observed, resulting in high net-positive budgets being regained. However, the frequency and intensity of climate-driven bleaching events are predicted to increase over the next decades. This would increase the spatial footprint of disturbances and exacerbate the magnitude of the changes described here, limiting the capacity of many reefs to maintain their geo-ecological functions. The enforcement of effective marine protection or the benefits of geographic isolation or of favourable environmental conditions (“refugia” sites) may offer the hope of more optimistic futures in some locations. A >plain language summary is available for this article.
Abstract.
Yarlett RT, Perry CT, Wilson RW, Philpot KE (2018). Constraining species-size class variability in rates of parrotfish bioerosion on Maldivian coral reefs: implications for regional-scale bioerosion estimates.
Marine Ecology Progress Series,
590, 155-169.
Abstract:
Constraining species-size class variability in rates of parrotfish bioerosion on Maldivian coral reefs: implications for regional-scale bioerosion estimates
Parrotfish are important bioeroders on coral reefs, and thus influence reef carbonate budgets and generate large volumes of carbonate sand that contribute to local beach and reef island maintenance. However, despite the importance of this process, there is a paucity of data with which variations in bioerosion rates as a function of species, feeding modes, and body size of parrotfish can be constrained. There is, in addition, limited knowledge regarding how resultant rates may vary within and between reef-building regions. Here, direct estimates of parrotfish bioerosion rates were quantified across different size classes of 6 common species of Maldivian parrotfish. These species comprise both ‘scraper’ and ‘excavator’ taxa, and our data indicate marked variations in mean bioerosion rates among these species. We also note that all species exhibited an apparent bimodal feeding cycle, with peaks in the late morning and early afternoon. Highest bioerosion rates were found in the ‘excavator’ Chlorurus strongylocephalus (~460 kg ind.-1 yr-1), nearly 130 times greater than rates calculated for comparably sized (>45 cm) ‘scraper’ species. Our data provide metrics that can be used in conjunction with parrotfish biomass or density data to improve estimates of parrotfish bioerosion on central Indian Ocean reefs, a region of high parrotfish density, but from which only limited metrics exist. We emphasise the importance of obtaining sub-regional scale process data to better inform estimates of reef bioerosion, especially to support attempts to model the impacts of fishing pressure, which commonly results in removal of high-rate bioeroding taxa.
Abstract.
Perry C (2018). Loss of coral reef growth capacity to track future increases in sea level. Nature
Perry C, Morgan KM (2017). Bleaching drives collapse in reef carbonate budgets and reef growth potential on southern Maldives reefs. Scientific Reports
Januchowski-Hartley FA, Graham NAJ, Wilson SK, Jennings S, Perry CT (2017). Drivers and predictions of coral reef carbonate budget trajectories.
Proceedings of the Royal Society B: Biological Sciences,
284(1847), 20162533-20162533.
Abstract:
Drivers and predictions of coral reef carbonate budget trajectories
Climate change is one of the greatest threats to the long-term maintenance of coral-dominated tropical ecosystems, and has received considerable attention over the past two decades. Coral bleaching and associated mortality events, which are predicted to become more frequent and intense, can alter the balance of different elements that are responsible for coral reef growth and maintenance. The geomorphic impacts of coral mass mortality have received relatively little attention, particularly questions concerning temporal recovery of reef carbonate production and the factors that promote resilience of reef growth potential. Here, we track the biological carbonate budgets of inner Seychelles reefs from 1994 to 2014, spanning the 1998 global bleaching event when these reefs lost more than 90% of coral cover. All 21 reefs had positive budgets in 1994, but in 2005 budgets were predominantly negative. By 2014, carbonate budgets on seven reefs were comparable with 1994, but on all reefs where an ecological regime shift to macroalgal dominance occurred, budgets remained negative through 2014. Reefs with higher massive coral cover, lower macroalgae cover and lower excavating parrotfish biomass in 1994 were more likely to have positive budgets post-bleaching. If mortality of corals from the 2016 bleaching event is as severe as that of 1998, our predictions based on past trends would suggest that six of eight reefs with positive budgets in 2014 would still have positive budgets by 2030. Our results highlight that reef accretion and framework maintenance cannot be assumed from the ecological state alone, and that managers should focus on conserving aspects of coral reefs that support resilient carbonate budgets.
Abstract.
Perry C, Kench P, Smithers S, Riegl B, Gulliver P, Daniells J (2017). Terrigenous sediment-dominated reef platform infilling: an unexpected precursor to reef island formation and a test of the reef platform size–island age model in the Pacific.
Coral Reefs,
36(3), 1013-1021.
Abstract:
Terrigenous sediment-dominated reef platform infilling: an unexpected precursor to reef island formation and a test of the reef platform size–island age model in the Pacific
Low-lying coral reef islands are considered highly vulnerable to climate change, necessitating an improved understanding of when and why they form, and how the timing of formation varies within and among regions. Several testable models have been proposed that explain inter-regional variability as a function of sea-level history and, more recently, a reef platform size model has been proposed from the Maldives (central Indian Ocean) to explain intra-regional (intra-atoll) variability. Here we present chronostratigraphic data from Pipon Island, northern Great Barrier Reef (GBR), enabling us to test the applicability of existing regional island evolution models, and the platform size control hypothesis in a Pacific context. We show that reef platform infilling occurred rapidly (~4–5 mm yr−1) under a “bucket-fill” type scenario. Unusually, this infilling was dominated by terrigenous sedimentation, with platform filling and subsequent reef flat formation complete by ~5000 calibrated years BP (cal BP). Reef flat exposure as sea levels slowly fell post highstand facilitated a shift towards intertidal and subaerial-dominated sedimentation. Our data suggest, however, a lag of ~1500 yr before island initiation (at ~3200 cal BP), i.e. later than that reported from smaller and more evolutionarily mature reef platforms in the region. Our data thus support: (1) the hypothesis that platform size acts to influence the timing of platform filling and subsequent island development at intra-regional scales; and (2) the hypothesis that the low wooded islands of the northern GBR conform to a model of island formation above an elevated reef flat under falling sea levels.
Abstract.
Morgan KM, Perry CT, Smithers SG, Johnson JA, Gulliver PA (2017). Transitions in coral reef accretion rates linked to intrinsic ecological shifts on turbid-zone nearshore reefs. Geology (Boulder)
East HK, Perry CT, Kench PS, Liang Y (2016). Atoll-scale comparisons of the sedimentary structure of coral reef rim islands, Huvadhu Atoll, Maldives.
JOURNAL OF COASTAL RESEARCH, 577-581.
Author URL.
Daw TM, Hicks CC, Brown K, Chaigneau T, Januchowski-Hartley FA, Cheung WWL, Rosendo S, Crona B, Coulthard S, Sandbrook C, et al (2016). Elasticity in ecosystem services: Exploring the variable relationship between ecosystems and human well-being.
Ecology and Society,
21(2).
Abstract:
Elasticity in ecosystem services: Exploring the variable relationship between ecosystems and human well-being
Although ecosystem services are increasingly recognized as benefits people obtain from nature, we still have a poor understanding of how they actually enhance multidimensional human well-being, and how well-being is affected by ecosystem change. We develop a concept of “ecosystem service elasticity” (ES elasticity) that describes the sensitivity of human well-being to changes in ecosystems. ES Elasticity is a result of complex social and ecological dynamics and is context dependent, individually variable, and likely to demonstrate nonlinear dynamics such as thresholds and hysteresis. We present a conceptual framework that unpacks the chain of causality from ecosystem stocks through flows, goods, value, and shares to contribute to the well-being of different people. This framework builds on previous conceptualizations, but places multidimensional well-being of different people as the final element. This ultimately disaggregated approach emphasizes how different people access benefits and how benefits match their needs or aspirations. Applying this framework to case studies of individual coastal ecosystem services in East Africa illustrates a wide range of social and ecological factors that can affect ES elasticity. For example, food web and habitat dynamics affect the sensitivity of different fisheries ecosystem services to ecological change. Meanwhile high cultural significance, or lack of alternatives enhance ES elasticity, while social mechanisms that prevent access can reduce elasticity. Mapping out how chains are interlinked illustrates how different types of value and the well-being of different people are linked to each other and to common ecological stocks. We suggest that examining chains for individual ecosystem services can suggest potential interventions aimed at poverty alleviation and sustainable ecosystems while mapping out of interlinkages between chains can help to identify possible ecosystem service trade-offs and winners and losers. We discuss conceptual and practical challenges of applying such a framework and conclude on its utility as a heuristic for structuring interdisciplinary analysis of ecosystem services and human wellbeing.
Abstract.
Morgan KM, Perry C, Smithers SG, Johnson JA, Daniell J (2016). Evidence of extensive reef development and high coral cover in nearshore environments: implications for understanding coral adaptation in turbid settings. Scientific Reports
Murphy GN, Perry CT, Chin P, McCoy C (2016). New approaches to quantifying bioerosion by endolithic sponge populations: applications to the coral reefs of Grand Cayman. Coral Reefs, 35(3), 1109-1121.
Perry CT, Steneck RS, Murphy GN, Kench PS, Edinger EN, Smithers SG, Mumby PJ (2015). Regional-scale dominance of non-framework building corals on Caribbean reefs affects carbonate production and future reef growth.
Global Change Biology,
21(3), 1153-1164.
Abstract:
Regional-scale dominance of non-framework building corals on Caribbean reefs affects carbonate production and future reef growth
Coral cover on Caribbean reefs has declined rapidly since the early 1980's. Diseases have been a major driver, decimating communities of framework building Acropora and Orbicella coral species, and reportedly leading to the emergence of novel coral assemblages often dominated by domed and plating species of the genera Agaricia, Porites and Siderastrea. These corals were not historically important Caribbean framework builders, and typically have much smaller stature and lower calcification rates, fuelling concerns over reef carbonate production and growth potential. Using data from 75 reefs from across the Caribbean we quantify: (i) the magnitude of non-framework building coral dominance throughout the region and (ii) the contribution of these corals to contemporary carbonate production. Our data show that live coral cover averages 18.2% across our sites and coral carbonate production 4.1 kg CaCO3 m-2 yr-1. However, non-framework building coral species dominate and are major carbonate producers at a high proportion of sites; they are more abundant than Acropora and Orbicella at 73% of sites; contribute an average 68% of the carbonate produced; and produce more than half the carbonate at 79% of sites. Coral cover and carbonate production rate are strongly correlated but, as relative abundance of non-framework building corals increases, average carbonate production rates decline. Consequently, the use of coral cover as a predictor of carbonate budget status, without species level production rate data, needs to be treated with caution. Our findings provide compelling evidence for the Caribbean-wide dominance of non-framework building coral taxa, and that these species are now major regional carbonate producers. However, because these species typically have lower calcification rates, continued transitions to states dominated by non-framework building coral species will further reduce carbonate production rates below 'predecline' levels, resulting in shifts towards negative carbonate budget states and reducing reef growth potential.
Abstract.
Perry C, Steneck RS, Murphy GN, Kench PS, Edinger EN, Smithers SG, Mumby PJ (2015). Regional-scale dominance of non-framework building corals on Caribbean reefs affects carbonate production and future reef growth. Global Change Biology, 21, 1153-1164.
Perry CT, Steneck RS, Murphy GN, Kench PS, Edinger EN, Smithers SG, Mumby PJ (2015). Regional-scale dominance of non-framework building corals on Caribbean reefs affects carbonate production and future reef growth.
Glob Chang Biol,
21(3), 1153-1164.
Abstract:
Regional-scale dominance of non-framework building corals on Caribbean reefs affects carbonate production and future reef growth.
Coral cover on Caribbean reefs has declined rapidly since the early 1980's. Diseases have been a major driver, decimating communities of framework building Acropora and Orbicella coral species, and reportedly leading to the emergence of novel coral assemblages often dominated by domed and plating species of the genera Agaricia, Porites and Siderastrea. These corals were not historically important Caribbean framework builders, and typically have much smaller stature and lower calcification rates, fuelling concerns over reef carbonate production and growth potential. Using data from 75 reefs from across the Caribbean we quantify: (i) the magnitude of non-framework building coral dominance throughout the region and (ii) the contribution of these corals to contemporary carbonate production. Our data show that live coral cover averages 18.2% across our sites and coral carbonate production 4.1 kg CaCO3 m(-2) yr(-1). However, non-framework building coral species dominate and are major carbonate producers at a high proportion of sites; they are more abundant than Acropora and Orbicella at 73% of sites; contribute an average 68% of the carbonate produced; and produce more than half the carbonate at 79% of sites. Coral cover and carbonate production rate are strongly correlated but, as relative abundance of non-framework building corals increases, average carbonate production rates decline. Consequently, the use of coral cover as a predictor of carbonate budget status, without species level production rate data, needs to be treated with caution. Our findings provide compelling evidence for the Caribbean-wide dominance of non-framework building coral taxa, and that these species are now major regional carbonate producers. However, because these species typically have lower calcification rates, continued transitions to states dominated by non-framework building coral species will further reduce carbonate production rates below 'predecline' levels, resulting in shifts towards negative carbonate budget states and reducing reef growth potential.
Abstract.
Author URL.
Perry CT, Murphy GN, Kench PS, Edinger EN, Smithers SG, Steneck RS, Mumby PJ (2014). Changing dynamics of Caribbean reef carbonate budgets: emergence of reef bioeroders as critical controls on present and future reef growth potential.
Proceedings. Biological sciences / the Royal Society,
281(1796).
Abstract:
Changing dynamics of Caribbean reef carbonate budgets: emergence of reef bioeroders as critical controls on present and future reef growth potential
© 2014 the Author(s) Published by the Royal Society. All rights reserved.Coral cover has declined rapidly on Caribbean reefs since the early 1980s, reducing carbonate production and reef growth. Using a cross-regional dataset, we show that widespread reductions in bioerosion rates-a key carbonate cycling process-have accompanied carbonate production declines. Bioerosion by parrotfish, urchins, endolithic sponges and microendoliths collectively averages 2 G (where G = kg CaCO3 m(-2) yr(-1)) (range 0.96-3.67 G). This rate is at least 75% lower than that reported from Caribbean reefs prior to their shift towards their present degraded state. Despite chronic overfishing, parrotfish are the dominant bioeroders, but erosion rates are reduced from averages of approximately 4 to 1.6 G. Urchin erosion rates have declined further and are functionally irrelevant to bioerosion on most reefs. These changes demonstrate a fundamental shift in Caribbean reef carbonate budget dynamics. To-date, reduced bioerosion rates have partially offset carbonate production declines, limiting the extent to which more widespread transitions to negative budget states have occurred. However, given the poor prognosis for coral recovery in the Caribbean and reported shifts to coral community states dominated by slower calcifying taxa, a continued transition from production to bioerosion-controlled budget states, which will increasingly threaten reef growth, is predicted.
Abstract.
Perry CT, Murphy GN, Kench PS, Edinger EN, Smithers SG, Steneck RS, Mumby PJ (2014). Changing dynamics of Caribbean reef carbonate budgets: emergence of reef bioeroders as critical controls on present and future reef growth potential.
Proc Biol Sci,
281(1796).
Abstract:
Changing dynamics of Caribbean reef carbonate budgets: emergence of reef bioeroders as critical controls on present and future reef growth potential.
Coral cover has declined rapidly on Caribbean reefs since the early 1980s, reducing carbonate production and reef growth. Using a cross-regional dataset, we show that widespread reductions in bioerosion rates-a key carbonate cycling process-have accompanied carbonate production declines. Bioerosion by parrotfish, urchins, endolithic sponges and microendoliths collectively averages 2 G (where G = kg CaCO3 m(-2) yr(-1)) (range 0.96-3.67 G). This rate is at least 75% lower than that reported from Caribbean reefs prior to their shift towards their present degraded state. Despite chronic overfishing, parrotfish are the dominant bioeroders, but erosion rates are reduced from averages of approximately 4 to 1.6 G. Urchin erosion rates have declined further and are functionally irrelevant to bioerosion on most reefs. These changes demonstrate a fundamental shift in Caribbean reef carbonate budget dynamics. To-date, reduced bioerosion rates have partially offset carbonate production declines, limiting the extent to which more widespread transitions to negative budget states have occurred. However, given the poor prognosis for coral recovery in the Caribbean and reported shifts to coral community states dominated by slower calcifying taxa, a continued transition from production to bioerosion-controlled budget states, which will increasingly threaten reef growth, is predicted.
Abstract.
Author URL.
Perry C, Steneck RS, Murphy GN, Kench PS, Edinger EN, Smithers SG, Mumby PJ (2014). Changing dynamics of Caribbean reef carbonate budgets: emergence of reef bioeroders as critical controls on present and future reef growth potential. Proceedings of the Royal Society of London: Biological Sciences, 281, 2014-2018.
Hepburn L, Blanchon P, Murphy G, Cousins L, Perry C (2014). Community structure and paleoecological implications of calcareous encrusters on artificial substrates across a Mexican reef. Coral Reefs, 34, 189-200.
Roche RC, Perry CT, Smithers SG, Leng MJ, Grove CA, Sloane HJ, Unsworth CE (2014). Mid-Holocene sea surface conditions and riverine influence on the inshore Great Barrier Reef.
Holocene,
24(8), 885-897.
Abstract:
Mid-Holocene sea surface conditions and riverine influence on the inshore Great Barrier Reef
We present measurements of Sr/Ca, δ18O, and spectral luminescence ratios (G/B) from a mid-Holocene Porites sp. microatoll recovered from the nearshore Great Barrier Reef (GBR). These records were used as proxies to reconstruct sea surface temperature (SST), the δ18O of surrounding seawater (δ18Osw), and riverine influence, respectively, and compared with records from a modern Porites sp. microatoll growing in the same environment. Strong riverine influence in the mid-Holocene record is indicated by (1) an increased annual δ18Osw range in the mid-Holocene record, (2) negative peaks in δ18O characteristic of flood events, and (3) a higher G/B luminescence ratio. Seasonal cycles in G/B suggest that humic acid inputs were elevated for a longer portion of the year during the mid-Holocene. The seasonal cycle of δ18Osw peaked earlier in the year in the mid-Holocene record relative to the modern, while mean δ18Osw values from the mid-Holocene record were similar to modern values. These records provide an insight into the oceanographic conditions the nearshore GBR experienced during mid-Holocene climatic shifts and are consistent with a strong Australian-Indonesian Summer Monsoon (AISM) system at ~ 4700 cal. yr BP. © the Author(s) 2014.
Abstract.
Roche RC, Perry C, Smithers SG, Leng MJ, Grove CA, Sloane HJ, Unsworth C (2014). Mid-Holocene sea surface conditions and riverine influence on the inshore Great Barrier Reef. The Holocene: a major interdisciplinary journal focusing on recent environmental change
Salter MA, Perry C, Wilson RW (2014). Size fraction analysis of fish-derived carbonates in shallow sub-tropical marine environments and a potentially unrecognised origin for peloidal carbonates. Sedimentary Geology, 314, 17-30.
Salter MA, Perry CT, Wilson RW (2014). Size fraction analysis of fish-derived carbonates in shallow sub-tropical marine environments and a potentially unrecognised origin for peloidal carbonates.
Sedimentary Geology,
314, 17-30.
Abstract:
Size fraction analysis of fish-derived carbonates in shallow sub-tropical marine environments and a potentially unrecognised origin for peloidal carbonates
Marine bony fish are now known as primary producers of calcium carbonate. Furthermore, within the shallow sub-tropical platform settings of the Bahamas, this production process has been shown to occur at rates relevant to carbonate sediment production budgets. Fish excrete these carbonates as loosely aggregated pellets which, post-excretion, exhibit a range of distinctive crystal morphologies and have mineralogies ranging from low (0-4mol% MgCO3) to high (4-40mol% MgCO3) Mg-calcites, aragonite and amorphous carbonate phases. Here we provide the first quantitative assessment of the size fractions of the carbonates produced by a range of tropical fish species, and document the extent of post-excretion carbonate pellet break down under a range of physical agitation conditions. Specifically, we document the morphologies and size fractions of: i) intact pellets at the point of excretion; ii) intact pellets after agitation in seawater; and iii) the particles released from pellets post-disaggregation. Results indicate that fish-derived pellets initially fall within the very fine to very coarse sand fractions. Exposure to conditions of moderate seawater agitation for 30days results in significant pellet diminution; 66% of initial pellet mass being released as individual particles, whilst 34% is retained as partially intact pellets that are smaller (fine sand-grade) and more rounded than initial pellets. In contrast, pellets exposed to very gently agitated conditions for up to 200days show little change. Where pellet disaggregation does occur, particles are commonly released as individual clay- and silt-grade crystals. However, some morphotypes (e.g. polycrystalline spheres) can be intergrown and are released as strongly cohesive particle clusters falling within the coarse silt to fine sand fractions. Only very vigorous agitation may disaggregate such particles, resulting in the release of their component clay-grade crystals. We conclude that fish-derived carbonates may thus contribute not only to the mud-fraction of marine carbonates, but also to the fine sand fraction as intergrown particles, and to the fine to coarse sand fractions as intact and partially intact pellets. These experimental data indicate that hydrodynamic regimes local to sites of excretion will influence the generation of carbonates with different size fraction ranges. Rapid pellet disaggregation is more likely in high energy settings, hypothesised to result in redistribution of liberated mud-grade particles to lower energy platform-top settings and/or off-platform. In contrast, pellets excreted in lower energy settings are more likely to be preserved intact, and are thus proposed as a previously unrecognised source of pelletal and peloidal carbonate sediments. •Break-up of carbonate pellets produced by marine bony fish is investigated. •Pellets can remain intact and may contribute to sedimentary pellets and peloids. •Rapid pellet break-up releases component particles in agitated settings. •Particle size ranges from clay to fine sand grade: different depositional fates. •Relevant to surface sediments in shallow sub-tropical marine provinces.
Abstract.
Berkeley A, Perry C, Smithers SG, Hoon SH (2014). Towards a formal description of foraminiferal assemblage formation in near shore environments: qualitative and quantitative concepts. Marine Micropalaeontology, 112, 27-38.
Gulliver P, Palmer S, Perry C, Smithers S (2013). Are coral clasts from a turbid near-shore reef environment a suitable material for radiocarbon analysis?.
Radiocarbon,
55(2-3), 624-630.
Abstract:
Are coral clasts from a turbid near-shore reef environment a suitable material for radiocarbon analysis?
Use of coral skeletons to determine growth histories of reefs situated in warm, clear tropical waters is well established. Recently, however, there has been increasing awareness of the significance of reefs occurring in environments that are considered as marginal for coral growth, such as turbid inshore settings characterized by episodes of elevated turbidity, low light penetration, and periodic sediment burial. While these conditions are generally considered as limiting for coral growth, coral reefs in these settings can exhibit high live coral cover and species diversity, and thus can be both ecologically and geologically significant. Turbid-zone reefs are also commonly concentrated along eroding shorelines with many analogues to erosional shorelines developed during the Holocene transgression. A growing number of studies of these previously undocumented reefs reveal that the reef deposits are detrital in nature, comprising a framework dominated by reef rubble and coral clasts and set within a fine-grained terrigenous sediment matrix. In addition to the recognized effects of diagenesis or algal encrustations on the radiocarbon signature of coral samples, episodic high-energy events may rework sediments and can result in age reversals in the same stratigraphic unit. As in other reef settings, the possibility of such reworking can complicate the reconstruction of turbid-zone reef growth chronologies. In order to test the accuracy of dating coral clasts for developing growth histories of these reef deposits, 5 replicate samples from 5 separate coral clasts were taken from 2 sedimentary units in a core collected from Paluma Shoals, an inshore turbid-zone reef located in Halifax Bay, central Great Barrier Reef, Australia. Results show that where care is taken to screen the clasts for skeletal preservation, primary mineralogical structures, and δ13C values indicative of marine carbonate, then reliable 14C dates can be recovered from individual turbid reef coral samples. In addition, the results show that these individual clasts were deposited coevally. © 2013 by the Arizona Board of Regents on behalf of the University of Arizona.
Abstract.
Kennedy EV, Perry CT, Halloran PR, Iglesias-Prieto R, Schönberg CHL, Wisshak M, Form AU, Carricart-Ganivet JP, Fine M, Eakin CM, et al (2013). Avoiding coral reef functional collapse requires local and global action.
Curr Biol,
23(10), 912-918.
Abstract:
Avoiding coral reef functional collapse requires local and global action.
Coral reefs face multiple anthropogenic threats, from pollution and overfishing to the dual effects of greenhouse gas emissions: rising sea temperature and ocean acidification. While the abundance of coral has declined in recent decades, the implications for humanity are difficult to quantify because they depend on ecosystem function rather than the corals themselves. Most reef functions and ecosystem services are founded on the ability of reefs to maintain their three-dimensional structure through net carbonate accumulation. Coral growth only constitutes part of a reef's carbonate budget; bioerosion processes are influential in determining the balance between net structural growth and disintegration. Here, we combine ecological models with carbonate budgets and drive the dynamics of Caribbean reefs with the latest generation of climate models. Budget reconstructions using documented ecological perturbations drive shallow (6-10 m) Caribbean forereefs toward an increasingly fragile carbonate balance. We then projected carbonate budgets toward 2080 and contrasted the benefits of local conservation and global action on climate change. Local management of fisheries (specifically, no-take marine reserves) and the watershed can delay reef loss by at least a decade under "business-as-usual" rises in greenhouse gas emissions. However, local action must be combined with a low-carbon economy to prevent degradation of reef structures and associated ecosystem services.
Abstract.
Author URL.
Browne NK, Smithers SG, Perry CT (2013). Carbonate and terrigenous sediment budgets for two inshore turbid reefs on the central Great Barrier Reef. Marine Geology, 346, 101-123.
Perry CT, Smithers SG, Gulliver P (2013). Rapid vertical accretion on a ‘young’ shore-detached turbid zone reef: Offshore Paluma Shoals, central Great Barrier Reef, Australia.
Coral Reefs, 1-6.
Author URL.
Perry CT, Kench PS, Smithers SG, Yamano H, O'Leary M, Gulliver P (2013). Time scales and modes of reef lagoon infilling in the maldives and controls on the onset of reef island formation.
Geology,
41(10), 1111-1114.
Abstract:
Time scales and modes of reef lagoon infilling in the maldives and controls on the onset of reef island formation
Faro are annular reefs, with reef fl ats near sea level and lagoons of variable depth, characteristic of both the perimeter and lagoons of Maldivian (Indian Ocean) atolls. Their geomorphic development remains largely unknown, but where faro lagoons (termed velu in Maldivian) have infilled and support reef islands, these provide precious habitable land. Understanding the timing and modes of velu infilling is thus directly relevant to questions about reef island development and vulnerability. Here we use a chronostratigraphic data set obtained from a range of atoll-interior faro with partially to fully filled velu (including those with reef islands) from Baa (South Maalhosmadulu) Atoll, Maldives, to determine time scales and modes of velu infilling, and to identify the temporal and spatial thresholds that control reef island formation. Our data suggest a systematic relationship between faro size, velu infilling, and island development. These relationships likely vary between atolls as a function of atoll lagoon depth, but in Baa Atoll, our data set indicates the following faro-size relationships exist: (1) faros 0.5 km2 but ~1.25 km2 have unfilled (deeper) velu which might only infill over long time scales and which are thus unlikely to support new island initiation. These new observations, when combined with previously published data on Maldivian reef island development, suggest that while the velu of the largest faro are unlikely to fill over the next few centuries (at least), other faro with near-infilled velu may provide important foci for future reef-island building, even under present highstand (and slightly rising) sea levels. © 2013 Geological Society of America.
Abstract.
Browne N, Smithers SG, Perry C, Ridd P (2012). A field based technique for measuring sediment flux on coral reefs: application to turbid reefs on the Great Barrier Reef. Journal of Coastal Research: an international forum for the littoral sciences, in press
Browne N, Smithers SG, Perry C (2012). Coral reefs of the turbid inner Great Barrier Reef: a geological perspective on occurrence, composition and growth. Earth-Science Reviews, in press
Browne NK, Smithers SG, Perry CT (2012). Coral reefs of the turbid inner-shelf of the Great Barrier Reef, Australia: an environmental and geomorphic perspective on their occurrence, composition and growth. Earth-Science Reviews, 115(1-2), 1-20.
Perry C, Edinger EN, Kench PS, Murphy G, Steneck RS, Smithers SG, Mumby PJ (2012). Estimating rates of biologically driven coral reef framework production and erosion: a new census-based carbonate budget methodology and applications to the reefs of Bonaire. Coral Reefs, in press
Perry C, Smithers SG, Gulliver P, Browne N (2012). Evidence of very rapid reef accretion and reef growth under high turbidity and terrigenous sedimentation. Geology (Boulder), 40, 719-722.
Salter MA, Perry CT, Wilson RW (2012). Production of mud-grade carbonates by marine fish: Crystalline products and their sedimentary significance. Sedimentology
Salter MA, Perry C, Wilson RW (2012). Production of mud-grade carbonates by marine fish: crystalline products and their sedimentary significance. Sedimentolology, in press
Browne NK, Smithers SG, Perry CT (2012). Spatial and temporal variations in turbidity on two inshore turbid reefs on the Great Barrier Reef, Australia. Coral Reefs, 32(1), 195-210.
Wilson RW, Reardon EE, Perry CT (2011). A fishy tale: a missing part of the inorganic ocean carbon cycle.
The Biochemist(June), 30-34.
Author URL.
Perry CT, Smithers SG (2011). Cycles of coral reef ‘turn-on’, rapid growth and ‘turn-off’ over the past 8,500 years: a context for understanding modern ecological states and trajectories. Global Change Biology, 17, 76-86.
Perry CT, Salter MA, Harborne AR, Crowley SF, Jelks HJ, Wilson RW (2011). Fish as major carbonate mud producers and missing components of the tropical carbonate factory. Proceedings of the National Academy of Science, 108, 3865-3869.
Perry CT, Salter MA, Harborne AR, Crowley SF, Jelks HL, Wilson RW (2011). Fish as major carbonate mud producers and missing components of the tropical carbonate factory.
Proc Natl Acad Sci U S A,
108(10), 3865-3869.
Abstract:
Fish as major carbonate mud producers and missing components of the tropical carbonate factory.
Carbonate mud is a major constituent of recent marine carbonate sediments and of ancient limestones, which contain unique records of changes in ocean chemistry and climate shifts in the geological past. However, the origin of carbonate mud is controversial and often problematic to resolve. Here we show that tropical marine fish produce and excrete various forms of precipitated (nonskeletal) calcium carbonate from their guts ("low" and "high" Mg-calcite and aragonite), but that very fine-grained (mostly < 2 μm) high Mg-calcite crystallites (i.e. > 4 mole % MgCO(3)) are their dominant excretory product. Crystallites from fish are morphologically diverse and species-specific, but all are unique relative to previously known biogenic and abiotic sources of carbonate within open marine systems. Using site specific fish biomass and carbonate excretion rate data we estimate that fish produce ∼6.1 × 10(6) kg CaCO(3)/year across the Bahamian archipelago, all as mud-grade (the < 63 μm fraction) carbonate and thus as a potential sediment constituent. Estimated contributions from fish to total carbonate mud production average ∼14% overall, and exceed 70% in specific habitats. Critically, we also document the widespread presence of these distinctive fish-derived carbonates in the finest sediment fractions from all habitat types in the Bahamas, demonstrating that these carbonates have direct relevance to contemporary carbonate sediment budgets. Fish thus represent a hitherto unrecognized but significant source of fine-grained carbonate sediment, the discovery of which has direct application to the conceptual ideas of how marine carbonate factories function both today and in the past.
Abstract.
Author URL.
Perry CT, Kench PS, Smithers SG, Riegl BR, Yamano H, O'Leary MJ (2011). Implications of reef ecosystem change for the stability and maintenance of coral reef islands. Global Change Biology, 17, 3679-3696.
Roche R, Perry CT, Johnson KG, Saltana K, Smithers SG, Thompson AA (2011). Mid-Holocene coral community data as a baseline for understanding contemporary reef ecological states. Palaeogeography, Palaeoclimatology, Palaeoecology, 299, 159-167.
Perry CT, Smithers SG, Wassenburg J, Roche R (2011). Recurrent patterns of coral community and sediment facies development through successive phases of Holocene reef growth and decline. Marine Geology, 289, 60-71.
Roche R, Abel RA, Johnson KG, Perry CT (2011). Spatial variation in porosity and skeletal element characteristics in apical tips of the branching coral Acropora pulchra (Brook 1891). Coral Reefs, 30, 195-201.
Perry CT, Smithers SG (2010). Evidence for the episodic 'turn-on' and ‘turn-off' of turbid-zone, inner-shelf coral reefs during the late Holocene sea-level highstand. Geology, 38, 119-122.
Browne N, Smithers SG, Perry CT (2010). Geomorphology and community structure of Middle Reef, central Great Barrier Reef, Australia: an inner-shelf turbid zone reef subjected to episodic mortality events. Coral Reefs, 26, 683-689.
O'Leary M, Perry CT (2010). Holocene reef accretion on the Rodrigues carbonate platform: an alternative to the classic ‘bucket-fill’ model. Geology, 38, 855-858.
Palmer SE, Perry CT, Smithers SG, Gulliver P (2010). Internal structure and accretionary history of a Holocene nearshore, turbid-zone coral reef: Paluma Shoals, central Great Barrier Reef, Australia. Marine Geology, 276, 14-29.
Roche R, Abel RA, Johnson KG, Perry CT (2010). Quantification of porosity in Acropora pulchra (Brook 1891) using X-ray micro-computed tomography techniques. Journal of Experimental Marine Biology & Ecology, 396, 1-9.
Berkeley A, Perry CT, Smithers SG (2010). Taphonomic signatures and patterns of test degradation on tropical, intertidal benthic foraminifera. Marine Micropalaeontology, 73, 148-163.
Berkeley A, Perry CT, Smithers SG, Horton BP, Cundy AB (2009). Foraminiferal biofacies across mangrove-mudflat environments at Cocoa Creek, north Queensland, Australia. Marine Geology, 263, 64-86.
Perry CT, Berkeley A (2009). Intertidal substrate modification as a result of mangrove planting: impacts of introduced mangrove species on sediment microfacies characteristics. Estuarine, Coastal and Shelf Science, 81, 225-237.
Perry CT, Smithers SG, Johnson KG (2009). Long-term coral community records from Lugger Shoal on the terrigenous inner-shelf of the central Great Barrier Reef, Australia. Coral Reefs, 28, 941-948.
Perry CT, Smithers SG (2009). Stabilisation of intertidal cobbles and gravels by Goniastrea aspera: an analogue for substrate colonisation during marine transgressions?. Coral Reefs, 28, 805-806.
O'Leary MJ, Perry CT, Turner J, Beavington-Penney SJ (2009). The significant role of sediment bio-retexturing within a contemporary carbonate
platform system: implications for carbonate microfacies development. Sedimentary Geology, 219, 169-179.
Perry CT, Smithers SG, Palmer SE, Larcombe P, Johnson KG (2008). A 1200 year paleoecological record of coral community development from the terrigenous inner-shelf of the Great Barrier Reef. Geology, 36, 691-694.
Perry CT, Spencer T, Kench PS (2008). Carbonate budgets and reef production states: a geomorphic perspective on the ecological phase-shift concept. Coral Reefs, 27, 853-866.
Perry CT, Berkeley A, Smithers SG (2008). Microfacies Characteristics of a Tropical, Mangrove-Fringed Shoreline, Cleveland Bay, Queensland, Australia: Sedimentary and Taphonomic Controls on Mangrove Facies Development. Journal of Sedimentary Research, 78(2), 77-97.
Perry CT, Berkeley A, Smithers SG (2008). Microfacies characteristics of a tropical, mangrove-fringed shoreline, Cleveland Bay, central Great Barrier Reef, Australia: mangrove sequence development and facies preservation. Journal of Sedimentary Research, 78, 77-97.
Perry CT, Hepburn LJ (2008). Syn-depositional alteration of coral reef framework through bioerosion, encrustation and cementation: taphonomic signatures of reef accretion and reef depositional events. Earth-Science Reviews, 86, 106-144.
Berkeley A, Perry CT, Smithers SG, Horton BP (2008). The spatial and vertical distribution of living (stained) benthic foraminifera from a tropical, intertidal environment, north Queensland, Australia. Marine Micropalaeontology, 69, 240-261.
Berkeley A, Perry CT, Smithers SG, Horton BP, Taylor KG (2007). A review of the ecological and taphonomic controls on foraminiferal assemblage development in intertidal environments. Earth-Science Reviews, 83(3-4), 205-230.
Taylor KG, Perry CT, Greenaway AM, Machent PG (2007). Bacterial iron oxide reduction in a terrigenous sediment-impacted tropical shallow marine carbonate system, north Jamaica. Marine Chemistry, 107(4), 449-463.
Mallela J, Perry CT (2006). Calcium carbonate budgets for two coral reefs affected by different terrestrial runoff regimes, Rio Bueno, Jamaica. Coral Reefs, 26(1), 129-145.
PERRY CT, TAYLOR KG (2006). Inhibition of dissolution within shallow water carbonate sediments: impacts of terrigenous sediment input on syn-depositional carbonate diagenesis. Sedimentology, 53(3), 495-513.
Perry CT, Smithers SG (2006). Taphonomic signatures of turbid-zone reef development: Examples from Paluma Shoals and Lugger Shoal, inshore central Great Barrier Reef, Australia. Palaeogeography, Palaeoclimatology, Palaeoecology, 242(1-2), 1-20.
Perry CT, Taylor KG, Machent PG (2006). Temporal shifts in reef lagoon sediment composition, Discovery Bay, Jamaica. Estuarine, Coastal and Shelf Science, 67(1-2), 133-144.
MACDONALD I, PERRY C, LARCOMBE P (2005). Comment on ?Rivers, runoff, and reefs? by McLaughlin et al. [Global Planetary Change 39 (2003) 191?199]. Global and Planetary Change, 45(4), 333-337.
Perry CT, Beavington-Penney SJ (2005). Epiphytic calcium carbonate production and facies development within sub-tropical seagrass beds, Inhaca Island, Mozambique. Sedimentary Geology, 174(3-4), 161-176.
Perry CT (2005). Morphology and occurrence of rhodoliths in siliciclastic, intertidal environments from a high latitude reef setting, southern Mozambique. Coral Reefs, 24(2), 201-207.
Perry CT (2005). Structure and development of detrital reef deposits in turbid nearshore environments, Inhaca Island, Mozambique. Marine Geology, 214(1-3), 143-161.
Chapters
Perry CT, Harborne AR (2016). Bioerosion on Modern Reefs: Impacts and Responses Under Changing Ecological and Environmental Conditions. In (Ed) Coral Reefs of the World, Springer Netherlands, 69-101.
Perry CT (2010). Carbonate budgets and reef framework accumulation. In (Ed) Encyclopaedia of Modern Coral Reefs, Springer-Verlag, 185-190.
Kench PS, Perry CT, Spencer T (2010). Coral Reefs. In (Ed) Geomorphology and Global Environmental Change: Landscape Scale Implications, Cambridge: Cambridge University Press, 180-213.
Perry CT (2010). Holocene high energy window. In Hopley D (Ed) Encyclopaedia of Modern Coral Reefs, Springer-Verlag, 558-561.
Perry CT (2010). Turbid-zone and terrigenous sediment-influenced reefs. In (Ed) Encyclopaedia of Modern Coral Reefs, Springer-Verlag, 1110-1120.
Publications by year
In Press
Lange I, Perry C (In Press). A quick, easy and non-invasive method to quantify coral growth rates using photogrammetry 1 and 3D model comparisons.
Methods in Ecology and EvolutionAbstract:
A quick, easy and non-invasive method to quantify coral growth rates using photogrammetry 1 and 3D model comparisons
1. Coral growth rates vary significantly with environmental conditions and are thus important indicators of coral health and reef carbonate production. Despite the importance of this metric, data are sparse for most coral genera and species globally, including for many key reef-building species. Traditional methods to obtain growth rates, such as coral coring or staining with Alizarin are destructive and only work for a limited number of species and morphological growth forms.
2. Emerging approaches, using underwater photogrammetry to create digital models of coral colonies, are providing novel and non-invasive ways to explore colony-scale growth patterns and to address existing knowledge gaps. We developed an easy-to-follow workflow to construct 3D models from overlapping photographs and to measure linear, radial and vertical extension rates of branching, massive and encrusting corals after aligning colony models from subsequent years.
3. The method presented here was applied to measure extension rates for 47 colonies of nine coral species in the remote Chagos Archipelago, Indian Ocean. Proposed image acquisition and software settings produced 3D models of consistently high resolution and detail (precision ≤0.2 mm) and variability in growth measurements was small despite manual alignment, clipping and ruler placement (standard deviation ≤0.9 mm). Measured extension rates for the Chagos Archipelago are similar to published rates in the Indo-Pacific where comparable data is available, and provide the first published rates for several species. For encrusting corals, the results emphasize the importance of differentiating between radial and vertical growth.
4. Photogrammetry and 3D model comparisons provide a fast, easy, inexpensive and non-invasive method to quantify coral growth rates for a range of species and morphological growth forms. The simplicity of the presented workflow encourages its repeatability and permits non-specialists to learn photogrammetry with the goal of obtaining coral growth rates. Coral growth rates are essential metrics to quantify functional consequences of ongoing community changes on coral reefs and expanded datasets for key coral taxa will aid predictions of geographic variations in coral reef response to increasing global stressors.
Abstract.
Lange I, Perry CT (In Press). Bleaching impacts on carbonate production in the Chagos Archipelago: influence of functional coral groups on carbonate budget trajectories. Coral Reefs
Salter M, Perry C (In Press). Calcium carbonate production by fish in temperate marine environments. Limnology and Oceanography, 1-42.
Lange ID, Perry CT, Alvarez-Filip L (In Press). Carbonate budgets as indicators of functional reef “health”: a critical review of data underpinning census-based methods and current knowledge gaps. Ecological Indicators
Perry C, Murphy GN, Kench PS, Smithers SG, Edinger EN, Steneck RS, Mumby PJ (In Press). Caribbean-wide decline in carbonate production threatens coral reef growth. Nature Communications(4).
Perry C, Salter M, Morgan K, Harborne A (In Press). Census estimates of algal and epiphytic carbonate production highlight tropical seagrass meadows as sediment production hotspots. Frontiers in Marine Science
East H, Perry C, Kench P, Liang Y, Gulliver P (In Press). Coral Reef Island Initiation and Development Under Higher Than Present Sea Levels. Geophysical Research Letters
Molina-Hernández A, Medellín-Maldonado F, Lange I, Perry C, Alvarez-Filip L (In Press). Coral reef erosion: in situ measurement on different dead coral substrates on a Caribbean reef. Limnology and Oceanography
Husband E, Perry CT, Lange ID (In Press). Estimating rates of coral carbonate production from aerial
3 and archive imagery by applying colony scale conversion metrics. Coral Reefs
de Bakker D, van Duyl FC, Perry CT, Meesters EH (In Press). Extreme spatial heterogeneity in carbonate accretion potential on a Caribbean fringing reef linked to local human disturbance gradients. Global Change Biology
Estrada-Saldivar N, Jordan-Dalhgren E, Rodriguez-Martinez R, Perry CT, Alvarez-Filip L (In Press). Functional consequences of the long-term decline of reef-building corals in the Caribbean: evidence of across-reef functional convergence. Royal Society Open Science
Perry C (In Press). Geo-ecological functions provided by coral reef fishes vary among regions and impact reef carbonate cycling regimes. Ecosphere
Perry C, Smithers SG, Kench PS, Pears B (In Press). Impacts of Severe Tropical Cyclone Yasi on nearshore, terrigenous sediment-dominated reefs of the central Great Barrier Reef, Australia. Geomorphology, 222, 92-105.
Perry C, Kench PS, O'Leary MJ, Morgan KM, Januchowski-Hartle F (In Press). Linking reef ecology to island-building: Parrotfish identified as major producers of island-building sediment in the Maldives. Geology (Boulder), 43, 503-506.
Morgan KM, Perry CT, Johnson J, Smithers SG (In Press). Nearshore turbid-zone corals exhibit high bleaching tolerance on the Great Barrier Reef following the 2016 ocean warming event. Frontiers in Marine Science
Johnson J, Perry CT, Smithers SG, Morgan KM, Santodomingo N, Johnson K (In Press). Palaeoecological records of coral community development
on a turbid, nearshore reef complex: baselines for assessing
ecological change. Coral Reefs
Salter MA, Harborne AR, Perry CT, Wilson RW (In Press). Phase heterogeneity in carbonate production by marine fish influences their roles in sediment generation and the inorganic carbon cycle. Scientific Reports
Perry C (In Press). Post-bleaching coral community change on southern Maldivian reefs: is there potential for rapid recovery?. Coral Reefs
Yarlett R, Perry C, Wilson RW (In Press). Quantifying production rates and size fractions of parrotfish-derived sediment: a key functional role on Maldivian coral reefs. Ecology and Evolution
Salter MA, Perry CT, Stuart-Smith R, Edgar GJ, Wilson RW, Harborne AR (In Press). Reef fish carbonate production assessments highlight regional variation in sedimentary significance. Geology
Salter MA, Perry C, Stuart-Smith RD, Edgar GJ, Wilson R, Harborne AR (In Press). Reef fish carbonate production assessments highlight regional variation in sedimentary significance (DATASET).
GeologyAbstract:
Reef fish carbonate production assessments highlight regional variation in sedimentary significance (DATASET)
Dataset for Salter et al. (2018) "Reef fish carbonate production assessments highlight regional variation in sedimentary significance" published in GEOLOGY
Abstract.
Perry C, Morgan K, Yarlett R (In Press). Reef habitat type and spatial extent as interacting controls on platform-scale carbonate budgets. Frontiers in Marine Science
Johnson J, Perry CT, Smithers SG, Morgan KM, Woodroffe SA (In Press). Reef shallowing is a critical driver of benthic foraminiferal assemblage composition on nearshore turbid-zone coral reefs. Palaeogeography, Palaeoclimatology, Palaeoecology
Perry C, Murphy G, Graham NAJ, Wilson SK, Januchowski-Hartley F, East H (In Press). Remote coral reefs can sustain high growth potential and may match future sea-level trends. Scientific Reports
Perry C (In Press). Seagrass meadows are important sources of reef island-building sediment. Communications Earth & Environment
Perry C, Morgan KM, Salter MA (In Press). Sediment generation by Halimeda on atoll interior coral reefs of the southern Maldives: a census-based approach for estimating carbonate production by calcareous green algae. Sedimentary Geology
Molina-Hernández A, González-Barrios F, Perry C, Alvarez-Filip L (In Press). Two decades of carbonate budget change on shifted coral reef assemblages: are these reefs being locked into low net budget states?. Proceeedings of the Royal Society: B
2023
Ghilardi M, Salter MA, Parravicini V, Ferse SCA, Rixen T, Wild C, Birkicht M, Perry CT, Berry A, Wilson RW, et al (2023). Temperature, species identity and morphological traits predict carbonate excretion and mineralogy in tropical reef fishes.
Nature Communications,
14(1).
Abstract:
Temperature, species identity and morphological traits predict carbonate excretion and mineralogy in tropical reef fishes
AbstractAnthropogenic pressures are restructuring coral reefs globally. Sound predictions of the expected changes in key reef functions require adequate knowledge of their drivers. Here we investigate the determinants of a poorly-studied yet relevant biogeochemical function sustained by marine bony fishes: the excretion of intestinal carbonates. Compiling carbonate excretion rates and mineralogical composition from 382 individual coral reef fishes (85 species and 35 families), we identify the environmental factors and fish traits that predict them. We find that body mass and relative intestinal length (RIL) are the strongest predictors of carbonate excretion. Larger fishes and those with longer intestines excrete disproportionately less carbonate per unit mass than smaller fishes and those with shorter intestines. The mineralogical composition of excreted carbonates is highly conserved within families, but also controlled by RIL and temperature. These results fundamentally advance our understanding of the role of fishes in inorganic carbon cycling and how this contribution will change as community composition shifts under increasing anthropogenic pressures.
Abstract.
2022
McWhorter J (2022). A Multidimensional Analysis of Climate Projections on the Great Barrier Reef.
Abstract:
A Multidimensional Analysis of Climate Projections on the Great Barrier Reef
Tropical coral reefs are increasingly threatened due to global warming. Corals live within a narrow thermal threshold making them one of the most sensitive species to changes in temperature. Recent warming events on the Great Barrier Reef (GBR) (2016, 2017, 2020) have caused mass coral mortality on approximately 30% of the reef (Bozec et al. 2020; Hughes, Kerry et al. 2018). This research focuses on the development and implementation of a 1-D semi-dynamic downscaling method to improve climate projections on the GBR. Coral stress metrics are used to provide detailed projections on the magnitude and frequency of warming for four socio-economic pathways (SSP) under the 6th phase of the Climate Model Intercomparison Project. Following a chapter on methods and model validation, the results in chapter 3 reveal the importance of adhering to the lowest possible emissions trajectory which limits warming to 1.5°C by the end of the century. This scenario keeps projected warming to slightly above current conditions. Under the higher emissions trajectories (~4°C and ~5°C of global average warming) coral stress metrics quadruple present-day warming conditions which would result in annual mass coral mortality events by 2080. In chapter 4, climate refugia have been identified from present-day conditions based on downscaled surface temperature outputs in agreement with observations. The lower emissions trajectories maintain these locations as refugia while the higher emissions trajectories reveal the loss of these increasingly valuable locations. Areas of climate refugia can be attributed to tidal and wind energy fluctuations providing relief from warming. However, this advantage does not persist after global warming exceeds ~3°C. Refugia are more likely to persist in the northern GBR under increased warming even though recent evidence suggests there are fewer refugia in this region. Atmospheric spatial patterns on the GBR under warming above ~3° C reveal a change in wind and shortwave radiation patterns driving a loss in the identified climate refugia locations. Lastly, stratification was tested in chapter 5 to determine if increases in stratification could provide thermal relief to bottom temperature waters from 0-50 m under increased warming into the future using downscaled bottom temperature projections. Chapter 5 results demonstrate that warming influences bottom temperatures of stratified locations, showing little support for deeper reefs to act as a climate refuge. The temporal, spatial, and bottom temperature analysis of downscaled climate projections provides insight into the consequences of a warming planet for the GBR and can be used to inform management and policy decisions to protect coral reefs.
Abstract.
Berry A (2022). Calcium carbonate production by teleost fish: an investigation into the effects of temperature and dietary calcium intake.
Abstract:
Calcium carbonate production by teleost fish: an investigation into the effects of temperature and dietary calcium intake
The marine environment is hyperosmotic to the tissues of marine teleost fish, which results in passive water loss and ion gain throughout their lifetime. In order to avoid dehydration, marine teleosts drink seawater. Ingested seawater travels through the digestive tract, where it is manipulated in order to absorb water and selected ions. Calcium carbonate (CaCO3) is precipitated as part of this process, and aids water absorption by removing Ca2+ (calcium) and HCO3- (bicarbonate) ions from solution. This precipitate (hereby referred to as carbonate), which also contains some MgCO¬3, is then excreted to the environment as a waste product, where it can dissolve or become part of the sediment. The precipitation and dissolution of carbonate forms the marine inorganic carbon cycle, which we have only recently understood that fish form a significant part. In chapter one of this thesis, I have reviewed the literature to explore the many factors that affect the production of gut carbonates by fish, including absolute quantity, composition and how they affect the fate of carbonate after excretion. In chapter two I have experimentally investigated the effect of low temperature, from 3 to 14 °C, on the quantity and composition of carbonate excreted by lumpfish, Cyclopterus lumpus. Between 3 and 7 °C, carbonate excretion increased with a Q10 of 3.50, which is comparable to other species, and had no effect on the incorporation of MgCO3. This confirms that carbonate excretion rate responds to temperatures
Abstract.
Perry C, Salter M, Lange I, Kochan D, Harborne A, Graham N (2022). Geo-ecological functions provided by coral reef fishes vary among regions and impact. reef carbonate cycling regimes - supporting data.
Lange I, Perry C, Stuhr M (2022). Recovery trends of reef carbonate budgets at remote coral atolls 6 years post-bleaching.
Limnology and OceanographyAbstract:
Recovery trends of reef carbonate budgets at remote coral atolls 6 years post-bleaching
Coral bleaching events and resultant changes in benthic community composition and population size structure can diminish the important geo-ecological functions reefs provide, including habitat provision and carbonate production to support reef accretion. Net reef carbonate budgets, the balance between carbonate production and erosion processes, are thus important functional indicators of reef health. This study quantifies changes in coral community composition and colony size structures, and the resultant reef carbonate budget trajectories after the 2015/2016 bleaching event in the remote Chagos Archipelago, Indian Ocean. ReefBudget surveys were conducted at 12 sites across three atolls in 2015, 2018 and 2021, with calculations of biological carbonate production and erosion supported by locally obtained calcification and bioerosion rates. Carbonate budgets (in G = kg CaCO3 m-2 yr-1) shifted from net positive states in 2015 (mean±SD: 3.8±2.6 G) to net negative states in 2018 (-2.4±1.4 G) in response to bleaching-driven mass coral mortality. By 2021, all sites were on a trajectory of recovery, but net budgets differed significantly between atolls (-2.0±1.7 to 2.2±1.4 G). At Salomon atoll, the 3-fold faster recovery of carbonate production and return to positive reef budget states only six years post-bleaching was associated with the persistence of high structural complexity and the rapid recovery of fast growing tabular Acropora spp. Inter-atoll differences in colony size distributions furthermore illustrate that coral identity and size class are more important predictors of reef functions and post-disturbance recovery speed than coral cover alone.
Abstract.
Lange I, Perry C, Stuhr M (2022). Recovery trends of reef carbonate budgets at remote coral atolls six years post-bleaching (dataset).
Abstract:
Recovery trends of reef carbonate budgets at remote coral atolls six years post-bleaching (dataset)
Coral bleaching events and resultant changes in benthic community composition and population size structure can diminish the important geo-ecological functions reefs provide, including habitat provision and carbonate production to support reef accretion. Net reef carbonate budgets, the balance between carbonate production and erosion processes, are thus important functional indicators of reef health. This study quantifies changes in coral community composition and colony size structures, and the resultant reef carbonate budget trajectories after the 2015/2016 bleaching event in the remote Chagos Archipelago, Indian Ocean. ReefBudget surveys were conducted at 12 sites across three atolls in 2015, 2018 and 2021, with calculations of biological carbonate production and erosion supported by locally obtained calcification and bioerosion rates. Carbonate budgets (in G = kg CaCO3 m-2 yr-1) shifted from net positive states in 2015 (mean±SD: 3.8±2.6 G) to net negative states in 2018 (-2.4±1.4 G) in response to bleaching-driven mass coral mortality. By 2021, all sites were on a trajectory of recovery, but net budgets differed significantly between atolls (-2.0±1.7 to 2.2±1.4 G). At Salomon atoll, the 3-fold faster recovery of carbonate production and return to positive reef budget states only six years post-bleaching was associated with the persistence of high structural complexity and the rapid recovery of fast growing tabular Acropora spp. Inter-atoll differences in colony size distributions furthermore illustrate that coral identity and size class are more important predictors of reef functions and post-disturbance recovery speed than coral cover alone.
Abstract.
Lange ID, Molina-Hernández A, Medellín-Maldonado F, Perry CT, Álvarez-Filip L (2022). Structure-from-motion photogrammetry demonstrates variability in coral growth within colonies and across habitats.
PLOS ONE,
17(11), e0277546-e0277546.
Abstract:
Structure-from-motion photogrammetry demonstrates variability in coral growth within colonies and across habitats
Coral growth is an important metric of coral health and underpins reef-scale functional attributes such as structural complexity and calcium carbonate production. There persists, however, a paucity of growth data for most reef-building regions, especially for coral species whose skeletal architecture prevents the use of traditional methods such as coring and Alizarin staining. We used structure-from-motion photogrammetry to quantify a range of colony-scale growth metrics for six coral species in the Mexican Caribbean and present a newly developed workflow to measure colony volume change over time. Our results provide the first growth metrics for two species that are now major space occupiers on Caribbean reefs, Agaricia agaricites and Agaricia tenuifolia. We also document higher linear extension, volume increase and calcification rates within back reef compared to fore reef environments for four other common species: Orbicella faveolata, Porites astreoides, Siderastrea siderea and Pseudodiploria strigosa. Linear extension rates in our study were lower than those obtained via computed tomography (CT) scans of coral cores from the same sites, as the photogrammetry method averages growth in all dimensions, while the CT method depicts growth only along the main growth axis (upwards). The comparison of direct volume change versus potential volume increase calculated from linear extension emphasizes the importance of assessing whole colony growth to improve calcification estimates. The method presented here provides an approach that can generate accurate calcification estimates alongside a range of other whole-colony growth metrics in a non-invasive way.
Abstract.
2021
Cornwall CE, Comeau S, Kornder NA, Perry CT, van Hooidonk R, DeCarlo TM, Pratchett MS, Anderson KD, Browne N, Carpenter R, et al (2021). Global declines in coral reef calcium carbonate production under ocean acidification and warming.
Proceedings of the National Academy of Sciences,
118(21).
Abstract:
Global declines in coral reef calcium carbonate production under ocean acidification and warming
Significance
. The growth of coral reefs is threatened by the dual stressors of ocean warming and acidification. Despite a wealth of studies assessing the impacts of climate change on individual taxa, projections of their impacts on coral reef net carbonate production are limited. By projecting impacts across 233 different locations, we demonstrate that the majority of coral reefs will be unable to maintain positive net carbonate production globally by the year 2100 under representative concentration pathways RCP4.5 and 8.5, while even under RCP2.6, coral reefs will suffer reduced accretion rates. Our results provide quantitative projections of how different climate change stressors will influence whole ecosystem carbonate production across coral reefs in all major ocean basins.
Abstract.
Pereira-Filho GH, Mendes VR, Perry CT, Shintate GI, Niz WC, Sawakuchi AO, Bastos AC, Giannini PCF, Motta FS, Millo C, et al (2021). Growing at the limit: Reef growth sensitivity to climate and oceanographic changes in the South Western Atlantic. Global and Planetary Change, 201, 103479-103479.
Yarlett R, Perry C, Wilson RW (2021). Quantifying production rates and size fractions of parrotfish-derived sediment: a key functional role on Maldivian coral reefs- supporting datasets.
Duvat VKE, Magnan AK, Perry CT, Spencer T, Bell JD, Wabnitz CCC, Webb AP, White I, McInnes KL, Gattuso JP, et al (2021). Risks to future atoll habitability from climate-driven environmental changes.
Wiley Interdisciplinary Reviews: Climate Change,
12(3).
Abstract:
Risks to future atoll habitability from climate-driven environmental changes
Recent assessments of future risk to atoll habitability have focused on island erosion and submergence, and have overlooked the effects of other climate-related drivers, as well as differences between ocean basins and island types. Here we investigate the cumulative risk arising from multiple drivers (sea-level rise; changes in rainfall, ocean–atmosphere oscillations and tropical cyclone intensity; ocean warming and acidification) to five Habitability Pillars: Land, Freshwater supply, Food supply, Settlements and infrastructure, and Economic activities. Risk is assessed for urban and rural islands of the Pacific and Indian Oceans, under RCP2.6 and RCP8.5, in 2050 and 2090, and considering a moderate adaptation scenario. Risks will be highest in the Western Pacific which will experience increased island destabilization together with a high threat to freshwater, and decreased land-based and marine food supply from reef-dependent fish and tuna and tuna-like resources. Risk accumulation will occur at a lower rate in the Central Pacific (lower pressure on land, with more limited cascading effects on other Habitability Pillars; increase in pelagic fish stocks) and the Central Indian Ocean (mostly experiencing increased land destabilization and reef degradation). Risk levels will vary significantly between urban islands, depending on geomorphology and local shoreline disturbances. Rural islands will experience less contrasting risk levels, but higher risks than urban islands in the second half of the century. This article is categorized under: Trans-Disciplinary Perspectives > Regional Reviews.
Abstract.
McWhorter JK, Halloran PR, Roff G, Skirving WJ, Perry CT, Mumby PJ (2021). The importance of 1.5°C warming for the Great Barrier Reef. Global Change Biology, 28(4), 1332-1341.
Lange ID, Benkwitt CE, McDevitt-Irwin JM, Tietjen KL, Taylor B, Chinkin M, Gunn RL, Palmisciano M, Steyaert M, Wilson B, et al (2021). Wave exposure shapes reef community composition and recovery trajectories at a remote coral atoll.
Coral Reefs,
40(6), 1819-1829.
Abstract:
Wave exposure shapes reef community composition and recovery trajectories at a remote coral atoll
AbstractIn a time of unprecedented ecological change, understanding natural biophysical relationships between reef resilience and physical drivers is of increasing importance. This study evaluates how wave forcing structures coral reef benthic community composition and recovery trajectories after the major 2015/2016 bleaching event in the remote Chagos Archipelago, Indian Ocean. Benthic cover and substrate rugosity were quantified from digital imagery at 23 fore reef sites around a small coral atoll (Salomon) in 2020 and compared to data from a similar survey in 2006 and opportunistic surveys in intermediate years. Cluster analysis and principal component analysis show strong separation of community composition between exposed (modelled wave exposure > 1000 J m−3) and sheltered sites (< 1000 J m−3) in 2020. This difference is driven by relatively high cover of Porites sp. other massive corals, encrusting corals, soft corals, rubble and dead table corals at sheltered sites versus high cover of pavement and sponges at exposed sites. Total coral cover and rugosity were also higher at sheltered sites. Adding data from previous years shows benthic community shifts from distinct exposure-driven assemblages and high live coral cover in 2006 towards bare pavement, dead Acropora tables and rubble after the 2015/2016 bleaching event. The subsequent recovery trajectories at sheltered and exposed sites are surprisingly parallel and lead communities towards their respective pre-bleaching communities. These results demonstrate that in the absence of human stressors, community patterns on fore reefs are strongly controlled by wave exposure, even during and after widespread coral loss from bleaching events.
Abstract.
Lange I, Perry C (2021). Wave exposure shapes reef community composition and recovery trajectories at a remote coral atoll (dataset).
Abstract:
Wave exposure shapes reef community composition and recovery trajectories at a remote coral atoll (dataset)
In a time of unprecedented ecological change, understanding natural biophysical relationships between reef resilience and physical drivers is of increasing importance. This study evaluates how wave forcing structures coral reef benthic community composition and recovery trajectories after the major 2015/2016 bleaching event in the remote Chagos Archipelago, Indian Ocean. Benthic cover and substrate rugosity were quantified from digital imagery at 23 fore reef sites around a small coral atoll (Salomon) in 2020 and compared to data from a similar survey in 2006 and opportunistic surveys in intermediate years. Cluster analysis and principal component analysis show strong separation of community composition between exposed (modelled wave exposure >1000 J m-3) and sheltered sites (
Abstract.
2020
Lange I, Perry C (2020). A quick, easy and non-invasive method to quantify coral growth rates using photogrammetry and 3D model comparisons (dataset).
Hays GC, Koldewey HJ, Andrzejaczek S, Attrill MJ, Barley S, Bayley DTI, Benkwitt CE, Block B, Schallert RJ, Carlisle AB, et al (2020). A review of a decade of lessons from one of the world’s largest MPAs: conservation gains and key challenges. Marine Biology, 167(11).
Perry CT, Morgan KM, Lange ID, Yarlett RT (2020). Bleaching-driven reef community shifts drive pulses of increased reef sediment generation.
Royal Society Open Science,
7(4), 192153-192153.
Abstract:
Bleaching-driven reef community shifts drive pulses of increased reef sediment generation
. The ecological impacts of coral bleaching on reef communities are well documented, but resultant impacts upon reef-derived sediment supply are poorly quantified. This is an important knowledge gap because these biogenic sediments underpin shoreline and reef island maintenance. Here, we explore the impacts of the 2016 bleaching event on sediment generation by two dominant sediment producers (parrotfish and
. Halimeda
. spp.) on southern Maldivian reefs. Our data identifies two pulses of increased sediment generation in the 3 years since bleaching. The first occurred within approximately six months after bleaching as parrotfish biomass and resultant erosion rates increased, probably in response to enhanced food availability. The second pulse occurred 1 to 3 years post-bleaching, after further increases in parrotfish biomass and a major (approx. fourfold) increase in
. Halimeda
. spp. abundance. Total estimated sediment generation from these two producers increased from approximately 0.5 kg CaCO
. 3
. m
. −2
. yr
. −1
. (pre-bleaching; 2016) to approximately 3.7 kg CaCO
. 3
. m
. −2
. yr
. −1
. (post-bleaching; 2019), highlighting the strong links between reef ecology and sediment generation. However, the relevance of this sediment for shoreline maintenance probably diverges with each producer group, with parrotfish-derived sediment a more appropriate size fraction to potentially contribute to local island shorelines.
.
Abstract.
Hattam C, Evans L, Morrissey K, Hooper T, Young K, Khalid F, Bryant M, Thani A, Slade L, Perry C, et al (2020). Building resilience in practice to support coral communities in the Western Indian Ocean. Environmental Science & Policy, 106, 182-190.
Yarlett RT, Perry CT, Wilson RW, Harborne AR (2020). Inter-Habitat Variability in Parrotfish Bioerosion Rates and Grazing Pressure on an Indian Ocean Reef Platform.
Diversity,
12(10), 381-381.
Abstract:
Inter-Habitat Variability in Parrotfish Bioerosion Rates and Grazing Pressure on an Indian Ocean Reef Platform
Parrotfish perform a variety of vital ecological functions on coral reefs, but we have little understanding of how these vary spatially as a result of inter-habitat variability in species assemblages. Here, we examine how two key ecological functions that result from parrotfish feeding, bioerosion and substrate grazing, vary between habitats over a reef scale in the central Maldives. Eight distinct habitats were delineated in early 2015, prior to the 2016 bleaching event, each supporting a unique parrotfish assemblage. Bioerosion rates varied from 0 to 0.84 ± 0.12 kg m−2 yr−1 but were highest in the coral rubble- and Pocillopora spp.-dominated habitat. Grazing pressure also varied markedly between habitats but followed a different inter-habitat pattern from that of bioerosion, with different contributing species. Total parrotfish grazing pressure ranged from 0 to ~264 ± 16% available substrate grazed yr-1 in the branching Acropora spp.-dominated habitat. Despite the importance of these functions in influencing reef-scale physical structure and ecological health, the highest rates occurred over less than 30% of the platform area. The results presented here provide new insights into within-reef variability in parrotfish ecological functions and demonstrate the importance of considering how these interact to influence reef geo-ecology.
Abstract.
Yarlett R, Perry C, Wilson RW, Harborne A (2020). Interhabitat Variability in Parrotfish Bioerosion Rates and Grazing Pressure on an Indian Ocean Reef Platform - Dataset.
East HK, Perry CT, Beetham EP, Kench PS, Liang Y (2020). Modelling reef hydrodynamics and sediment mobility under sea level rise in atoll reef island systems. Global and Planetary Change, 192, 103196-103196.
Salter MA, Rodríguez-Martínez RE, Álvarez-Filip L, Jordán-Dahlgren E, Perry CT (2020). Pelagic Sargassum as an emerging vector of high rate carbonate sediment import to tropical Atlantic coastlines. Global and Planetary Change, 103332-103332.
Morgan KM, Perry CT, Arthur R, Williams HTP, Smithers SG (2020). Projections of coral cover and habitat change on turbid reefs under future sea-level rise.
Proceedings. Biological sciences,
287(1929), 20200541-20200541.
Abstract:
Projections of coral cover and habitat change on turbid reefs under future sea-level rise
Global sea-level rise (SLR) is projected to increase water depths above coral reefs. Although the impacts of climate disturbance events on coral cover and three-dimensional complexity are well documented, knowledge of how higher sea levels will influence future reef habitat extent and bioconstruction is limited. Here, we use 31 reef cores, coupled with detailed benthic ecological data, from turbid reefs on the central Great Barrier Reef, Australia, to model broad-scale changes in reef habitat following adjustments to reef geomorphology under different SLR scenarios. Model outputs show that modest increases in relative water depth above reefs (Representative Concentration Pathway (RCP) 4.5) over the next 100 years will increase the spatial extent of habitats with low coral cover and generic diversity. More severe SLR (RCP8.5) will completely submerge reef flats and move reef slope coral communities below the euphotic depth, despite the high vertical accretion rates that characterize these reefs. Our findings suggest adverse future trajectories associated with high emission climate scenarios which could threaten turbid reefs globally and their capacity to act as coral refugia from climate change.
Abstract.
Lange ID, Perry CT, Morgan KM, Roche R, Benkwitt CE, Graham NAJ (2020). Site-Level Variation in Parrotfish Grazing and Bioerosion as a Function of Species-Specific Feeding Metrics.
Diversity,
12(10), 379-379.
Abstract:
Site-Level Variation in Parrotfish Grazing and Bioerosion as a Function of Species-Specific Feeding Metrics
Parrotfish provide important ecological functions on coral reefs, including the provision of new settlement space through grazing and the generation of sediment through bioerosion of reef substrate. Estimating these functions at an ecosystem level depends on accurately quantifying the functional impact of individuals, yet parrotfish feeding metrics are only available for a limited range of sites, species and size classes. We quantified bite rates, proportion of bites leaving scars and scar sizes in situ for the dominant excavator (Cetoscarus ocellatus, Chlorurus strongylocephalus, Ch. sordidus) and scraper species (Scarus rubroviolaceus, S. frenatus, S. niger, S. tricolor, S. scaber, S. psittacus) in the central Indian Ocean. This includes the first record of scar frequencies and sizes for the latter three species. Bite rates varied with species and life phase and decreased with body size. The proportion of bites leaving scars and scar sizes differed among species and increased with body size. Species-level allometric relationships between body size and each of these feeding metrics were used to parameterize annual individual grazing and bioerosion rates which increase non-linearly with body size. Large individuals of C. ocellatus, Ch. strongylocephalus and S. rubroviolaceus can graze 200–400 m2 and erode >500 kg of reef substrate annually. Smaller species graze 1–100 m2 yr−1 and erode 0.2–30 kg yr−1. We used these individual functional rates to quantify community grazing and bioerosion levels at 15 sites across the Maldives and the Chagos Archipelago. Although parrotfish density was 2.6 times higher on Maldivian reefs, average grazing (3.9 ± 1.4 m2 m−2 reef yr−1) and bioerosion levels (3.1 ± 1.2 kg m−2 reef yr−1) were about 15% lower than in the Chagos Archipelago (4.5 ± 2.3 and 3.7 ± 3.0, respectively), due to the dominance of small species and individuals in the Maldives (90% <30 cm length). This demonstrates that large-bodied species and individuals contribute disproportionally to both grazing and bioerosion. Across all sites, grazing increased by 66 ± 5 m2 ha−1 and bioerosion by 109 ± 9 kg ha−1 for every kg increase in parrotfish biomass. However, for a given level of parrotfish biomass, grazing and bioerosion levels were higher on Maldivian reefs than in the Chagos Archipelago. This suggests that small-bodied fish assemblages can maintain ecosystem functions, but only if key species are present in sufficiently high numbers.
Abstract.
Lange I, Perry C (2020). Site-level variation in parrotfish grazing and bioerosion as a function of species-specific feeding metrics (dataset).
Abstract:
Site-level variation in parrotfish grazing and bioerosion as a function of species-specific feeding metrics (dataset)
Parrotfish provide important ecological functions on coral reefs, including the provision of new settlement space through grazing and the generation of sediment through bioerosion of reef substrate. Estimating these functions at an ecosystem level depends on accurately quantifying the functional impact of individuals, yet parrotfish feeding metrics are only available for a limited range of sites, species and size classes. We quantified bite rates, proportion of bites leaving scars and scar sizes in situ for the dominant excavator (Cetoscarus ocellatus, Chlorurus strongylocephalus, Ch. sordidus) and scraper species (Scarus rubroviolaceus, S. frenatus, S. niger, S. tricolor, S. scaber, S. psittacus) in the central Indian Ocean. This includes the first record of scar frequencies and sizes for the latter three species. Bite rates varied with species and life phase and decreased with body size. The proportion of bites leaving scars and scar sizes differed among species and increased with body size. Species-level allometric relationships between body size and each of these feeding metrics were used to parameterize annual individual grazing and bioerosion rates which increase non-linearly with body size. Large individuals of C. ocellatus, Ch. strongylocephalus. and S. rubroviolaceus can graze 200–400 m2 and erode >500 kg of reef substrate annually. Smaller species graze 1–100 m2 yr−1 and erode 0.2–30 kg yr−1. We used these individual functional rates to quantify community grazing and bioerosion levels at 15 sites across the Maldives and the Chagos Archipelago. Although parrotfish density was 2.6 times higher on Maldivian reefs, average grazing (3.9 ± 1.4 m2 m−2 reef yr−1) and bioerosion levels (3.1 ± 1.2 kg m−2 reef yr−1) were about 15% lower than in the Chagos Archipelago (4.5 ± 2.3 and 3.7 ± 3.0, respectively), due to the dominance of small species and individuals in the Maldives (90%
Abstract.
Winter G, Storlazzi C, Vitousek S, van Dongeren A, McCall R, Hoeke R, Skirving W, Marra J, Reyns J, Aucan J, et al (2020). Steps to Develop Early Warning Systems and Future Scenarios of Storm Wave-Driven Flooding Along Coral Reef-Lined Coasts. Frontiers in Marine Science, 7
2019
Perry CT, Alvarez-Filip L (2019). Changing geo-ecological functions of coral reefs in the Anthropocene.
Functional Ecology,
33(6), 976-988.
Abstract:
Changing geo-ecological functions of coral reefs in the Anthropocene
The ecology of many coral reefs has changed markedly over recent decades in response to various combinations of local and global stressors. These ecological changes have important implications for the abundance of taxa that regulate the production and erosion of skeletal carbonates, and thus for many of the geo-ecological functions that coral reefs provide, including reef framework production and sediment generation, the maintenance of reef habitat complexity and reef growth potential. These functional attributes underpin many of the ecosystem goods and services that reefs provide to society. Rapidly changing conditions of reefs in the Anthropocene are likely to significantly impact the capacity of reefs to sustain these geo-ecological functions. Although the Anthropocene footprint of disturbance will be expressed differently across ecoregions and habitats, the end point for many reefs may be broadly similar: (a) progressively shifting towards net neutral or negative carbonate budget states; (b) becoming structurally flatter; and (c) having lower vertical growth rates. It is also likely that a progressive depth-homogenisation will occur in terms of these processes. The Anthropocene is likely to be defined by an increasing disconnect between the ecological processes that drive carbonate production on the reef surface, and the net geological outcome of that production, that is, the accumulation of the underlying reef structure. Reef structures are thus likely to become increasingly relict or senescent features, which will reduce reef habitat complexity and sediment generation rates, and limit reef potential to accrete vertically at rates that can track rising sea levels. In the absence of pervasive stressors, recovery of degraded coral communities has been observed, resulting in high net-positive budgets being regained. However, the frequency and intensity of climate-driven bleaching events are predicted to increase over the next decades. This would increase the spatial footprint of disturbances and exacerbate the magnitude of the changes described here, limiting the capacity of many reefs to maintain their geo-ecological functions. The enforcement of effective marine protection or the benefits of geographic isolation or of favourable environmental conditions (“refugia” sites) may offer the hope of more optimistic futures in some locations. A >plain language summary is available for this article.
Abstract.
Husband E (2019). Coral Colony-Scale Rugosity Metrics and Applications for Assessing Temporal Trends in the Structural Complexity of Coral Reefs.
Abstract:
Coral Colony-Scale Rugosity Metrics and Applications for Assessing Temporal Trends in the Structural Complexity of Coral Reefs.
Globally, coral reefs are experiencing reductions in structural complexity, primarily due to a loss of key reef building taxa. Monitoring these changes is difficult due to the time-consuming nature of in-situ measurements and lack of data concerning coral genus-specific contributions to reef structure. This research aimed to develop a new technique that uses coral colony level data to quantify reef rugosity (a 3-dimensional measure of reef structure) from three sources of coral survey data: 2D video imagery, line intercept data and UAV imagery. A database of coral colony rugosity data, comparing coral colony planar and contour length for 40 coral genera, 14 morphotypes and 9 abiotic reef substrates, was created using measurements from the Great Barrier Reef and Natural History Museum. Mean genus rugosity was identified as a key trait related to coral life history strategy. Linear regression analyses (y = mx) revealed statistically significant (p < 0.05) relationships between coral colony size and rugosity for every coral genus, morphotype and substrate. The gradient governing these relationships was unique for each coral taxa, ranging from mean = 1.23, for (encrusting) Acanthastrea, to m = 3.84, for (vase-shape) Merulina. These gradients were used as conversion factors to calculate reef rugosity from linear distances measured in video transects of both artificial reefs, used as a control test, and in-situ natural coral reefs, using Kinovea software. This calculated, ‘virtual’ rugosity had a strong, positive relationship with in-situ microscale rugosity (r2 = 0.96) measured from the control transects, but not with that measured at the meso-scale in natural, highly heterogeneous reef environments (r2 < 0.2). This showed that the technique can provide accurate rugosity information when considered at the coral colony level. The conversion factors were also applied to historic line intercept data from the Seychelles, where temporal changes in calculated rugosity were consistent with changes in coral cover between 2008 and 2017. Finally, on application to 2,283 corals digitised from UAV imagery of the Maldives, the conversion factors enabled calculation of rugosity for three 100 m2 reef areas and prediction of how this rugosity will decrease during two future scenarios of coral reef degradation and community change. The study highlights that the application of genera-specific coral rugosity data to both new and existing coral reef survey datasets could be a valuable tool for monitoring reef structural complexity over large spatial scales.
Abstract.
2018
Yarlett RT, Perry CT, Wilson RW, Philpot KE (2018). Constraining species-size class variability in rates of parrotfish bioerosion on Maldivian coral reefs: Implications for regional-scale bioerosion estimates.
Marine Ecology Progress Series,
590, 155-169.
Abstract:
Constraining species-size class variability in rates of parrotfish bioerosion on Maldivian coral reefs: Implications for regional-scale bioerosion estimates
Parrotfish are important bioeroders on coral reefs, and thus influence reef carbonate budgets and generate large volumes of carbonate sand that contribute to local beach and reef island maintenance. However, despite the importance of this process, there is a paucity of data with which variations in bioerosion rates as a function of species, feeding modes, and body size of parrotfish can be constrained. There is, in addition, limited knowledge regarding how resultant rates may vary within and between reef-building regions. Here, direct estimates of parrotfish bioerosion rates were quantified across different size classes of 6 common species of Maldivian parrotfish. These species comprise both 'scraper' and 'excavator' taxa, and our data indicate marked variations in mean bioerosion rates among these species. We also note that all species exhibited an apparent bimodal feeding cycle, with peaks in the late morning and early afternoon. Highest bioerosion rates were found in the 'excavator' Chlorurus strongylocephalus (∼460 kg ind.-1 yr-1), nearly 130 times greater than rates calculated for comparably sized (>45 cm) 'scraper' species. Our data provide metrics that can be used in conjunction with parrotfish biomass or density data to improve estimates of parrotfish bioerosion on central Indian Ocean reefs, a region of high parrotfish density, but from which only limited metrics exist. We emphasise the importance of obtaining sub-regional scale process data to better inform estimates of reef bioerosion, especially to support attempts to model the impacts of fishing pressure, which commonly results in removal of high-rate bioeroding taxa.
Abstract.
Yarlett RT, Perry CT, Wilson RW, Philpot KE (2018). Constraining species-size class variability in rates of parrotfish bioerosion on Maldivian coral reefs: implications for regional-scale bioerosion estimates.
Marine Ecology Progress Series,
590, 155-169.
Abstract:
Constraining species-size class variability in rates of parrotfish bioerosion on Maldivian coral reefs: implications for regional-scale bioerosion estimates
Parrotfish are important bioeroders on coral reefs, and thus influence reef carbonate budgets and generate large volumes of carbonate sand that contribute to local beach and reef island maintenance. However, despite the importance of this process, there is a paucity of data with which variations in bioerosion rates as a function of species, feeding modes, and body size of parrotfish can be constrained. There is, in addition, limited knowledge regarding how resultant rates may vary within and between reef-building regions. Here, direct estimates of parrotfish bioerosion rates were quantified across different size classes of 6 common species of Maldivian parrotfish. These species comprise both ‘scraper’ and ‘excavator’ taxa, and our data indicate marked variations in mean bioerosion rates among these species. We also note that all species exhibited an apparent bimodal feeding cycle, with peaks in the late morning and early afternoon. Highest bioerosion rates were found in the ‘excavator’ Chlorurus strongylocephalus (~460 kg ind.-1 yr-1), nearly 130 times greater than rates calculated for comparably sized (>45 cm) ‘scraper’ species. Our data provide metrics that can be used in conjunction with parrotfish biomass or density data to improve estimates of parrotfish bioerosion on central Indian Ocean reefs, a region of high parrotfish density, but from which only limited metrics exist. We emphasise the importance of obtaining sub-regional scale process data to better inform estimates of reef bioerosion, especially to support attempts to model the impacts of fishing pressure, which commonly results in removal of high-rate bioeroding taxa.
Abstract.
Perry C (2018). Loss of coral reef growth capacity to track future increases in sea level. Nature
Yarlett R, Perry C (2018). Parrotfish bite rates.
Abstract:
Parrotfish bite rates
Raw field data
Abstract.
2017
Perry C, Morgan KM (2017). Bleaching drives collapse in reef carbonate budgets and reef growth potential on southern Maldives reefs. Scientific Reports
Januchowski-Hartley FA, Graham NAJ, Wilson SK, Jennings S, Perry CT (2017). Drivers and predictions of coral reef carbonate budget trajectories.
Proceedings of the Royal Society B: Biological Sciences,
284(1847), 20162533-20162533.
Abstract:
Drivers and predictions of coral reef carbonate budget trajectories
Climate change is one of the greatest threats to the long-term maintenance of coral-dominated tropical ecosystems, and has received considerable attention over the past two decades. Coral bleaching and associated mortality events, which are predicted to become more frequent and intense, can alter the balance of different elements that are responsible for coral reef growth and maintenance. The geomorphic impacts of coral mass mortality have received relatively little attention, particularly questions concerning temporal recovery of reef carbonate production and the factors that promote resilience of reef growth potential. Here, we track the biological carbonate budgets of inner Seychelles reefs from 1994 to 2014, spanning the 1998 global bleaching event when these reefs lost more than 90% of coral cover. All 21 reefs had positive budgets in 1994, but in 2005 budgets were predominantly negative. By 2014, carbonate budgets on seven reefs were comparable with 1994, but on all reefs where an ecological regime shift to macroalgal dominance occurred, budgets remained negative through 2014. Reefs with higher massive coral cover, lower macroalgae cover and lower excavating parrotfish biomass in 1994 were more likely to have positive budgets post-bleaching. If mortality of corals from the 2016 bleaching event is as severe as that of 1998, our predictions based on past trends would suggest that six of eight reefs with positive budgets in 2014 would still have positive budgets by 2030. Our results highlight that reef accretion and framework maintenance cannot be assumed from the ecological state alone, and that managers should focus on conserving aspects of coral reefs that support resilient carbonate budgets.
Abstract.
Perry C, Kench P, Smithers S, Riegl B, Gulliver P, Daniells J (2017). Terrigenous sediment-dominated reef platform infilling: an unexpected precursor to reef island formation and a test of the reef platform size–island age model in the Pacific.
Coral Reefs,
36(3), 1013-1021.
Abstract:
Terrigenous sediment-dominated reef platform infilling: an unexpected precursor to reef island formation and a test of the reef platform size–island age model in the Pacific
Low-lying coral reef islands are considered highly vulnerable to climate change, necessitating an improved understanding of when and why they form, and how the timing of formation varies within and among regions. Several testable models have been proposed that explain inter-regional variability as a function of sea-level history and, more recently, a reef platform size model has been proposed from the Maldives (central Indian Ocean) to explain intra-regional (intra-atoll) variability. Here we present chronostratigraphic data from Pipon Island, northern Great Barrier Reef (GBR), enabling us to test the applicability of existing regional island evolution models, and the platform size control hypothesis in a Pacific context. We show that reef platform infilling occurred rapidly (~4–5 mm yr−1) under a “bucket-fill” type scenario. Unusually, this infilling was dominated by terrigenous sedimentation, with platform filling and subsequent reef flat formation complete by ~5000 calibrated years BP (cal BP). Reef flat exposure as sea levels slowly fell post highstand facilitated a shift towards intertidal and subaerial-dominated sedimentation. Our data suggest, however, a lag of ~1500 yr before island initiation (at ~3200 cal BP), i.e. later than that reported from smaller and more evolutionarily mature reef platforms in the region. Our data thus support: (1) the hypothesis that platform size acts to influence the timing of platform filling and subsequent island development at intra-regional scales; and (2) the hypothesis that the low wooded islands of the northern GBR conform to a model of island formation above an elevated reef flat under falling sea levels.
Abstract.
Morgan KM, Perry CT, Smithers SG, Johnson JA, Gulliver PA (2017). Transitions in coral reef accretion rates linked to intrinsic ecological shifts on turbid-zone nearshore reefs. Geology (Boulder)
2016
East HK, Perry CT, Kench PS, Liang Y (2016). Atoll-scale comparisons of the sedimentary structure of coral reef rim islands, Huvadhu Atoll, Maldives.
JOURNAL OF COASTAL RESEARCH, 577-581.
Author URL.
Perry CT, Harborne AR (2016). Bioerosion on Modern Reefs: Impacts and Responses Under Changing Ecological and Environmental Conditions. In (Ed) Coral Reefs of the World, Springer Netherlands, 69-101.
Daw TM, Hicks CC, Brown K, Chaigneau T, Januchowski-Hartley FA, Cheung WWL, Rosendo S, Crona B, Coulthard S, Sandbrook C, et al (2016). Elasticity in ecosystem services: Exploring the variable relationship between ecosystems and human well-being.
Ecology and Society,
21(2).
Abstract:
Elasticity in ecosystem services: Exploring the variable relationship between ecosystems and human well-being
Although ecosystem services are increasingly recognized as benefits people obtain from nature, we still have a poor understanding of how they actually enhance multidimensional human well-being, and how well-being is affected by ecosystem change. We develop a concept of “ecosystem service elasticity” (ES elasticity) that describes the sensitivity of human well-being to changes in ecosystems. ES Elasticity is a result of complex social and ecological dynamics and is context dependent, individually variable, and likely to demonstrate nonlinear dynamics such as thresholds and hysteresis. We present a conceptual framework that unpacks the chain of causality from ecosystem stocks through flows, goods, value, and shares to contribute to the well-being of different people. This framework builds on previous conceptualizations, but places multidimensional well-being of different people as the final element. This ultimately disaggregated approach emphasizes how different people access benefits and how benefits match their needs or aspirations. Applying this framework to case studies of individual coastal ecosystem services in East Africa illustrates a wide range of social and ecological factors that can affect ES elasticity. For example, food web and habitat dynamics affect the sensitivity of different fisheries ecosystem services to ecological change. Meanwhile high cultural significance, or lack of alternatives enhance ES elasticity, while social mechanisms that prevent access can reduce elasticity. Mapping out how chains are interlinked illustrates how different types of value and the well-being of different people are linked to each other and to common ecological stocks. We suggest that examining chains for individual ecosystem services can suggest potential interventions aimed at poverty alleviation and sustainable ecosystems while mapping out of interlinkages between chains can help to identify possible ecosystem service trade-offs and winners and losers. We discuss conceptual and practical challenges of applying such a framework and conclude on its utility as a heuristic for structuring interdisciplinary analysis of ecosystem services and human wellbeing.
Abstract.
Morgan KM, Perry C, Smithers SG, Johnson JA, Daniell J (2016). Evidence of extensive reef development and high coral cover in nearshore environments: implications for understanding coral adaptation in turbid settings. Scientific Reports
Murphy GN, Perry CT, Chin P, McCoy C (2016). New approaches to quantifying bioerosion by endolithic sponge populations: applications to the coral reefs of Grand Cayman. Coral Reefs, 35(3), 1109-1121.
2015
Perry CT, Steneck RS, Murphy GN, Kench PS, Edinger EN, Smithers SG, Mumby PJ (2015). Regional-scale dominance of non-framework building corals on Caribbean reefs affects carbonate production and future reef growth.
Global Change Biology,
21(3), 1153-1164.
Abstract:
Regional-scale dominance of non-framework building corals on Caribbean reefs affects carbonate production and future reef growth
Coral cover on Caribbean reefs has declined rapidly since the early 1980's. Diseases have been a major driver, decimating communities of framework building Acropora and Orbicella coral species, and reportedly leading to the emergence of novel coral assemblages often dominated by domed and plating species of the genera Agaricia, Porites and Siderastrea. These corals were not historically important Caribbean framework builders, and typically have much smaller stature and lower calcification rates, fuelling concerns over reef carbonate production and growth potential. Using data from 75 reefs from across the Caribbean we quantify: (i) the magnitude of non-framework building coral dominance throughout the region and (ii) the contribution of these corals to contemporary carbonate production. Our data show that live coral cover averages 18.2% across our sites and coral carbonate production 4.1 kg CaCO3 m-2 yr-1. However, non-framework building coral species dominate and are major carbonate producers at a high proportion of sites; they are more abundant than Acropora and Orbicella at 73% of sites; contribute an average 68% of the carbonate produced; and produce more than half the carbonate at 79% of sites. Coral cover and carbonate production rate are strongly correlated but, as relative abundance of non-framework building corals increases, average carbonate production rates decline. Consequently, the use of coral cover as a predictor of carbonate budget status, without species level production rate data, needs to be treated with caution. Our findings provide compelling evidence for the Caribbean-wide dominance of non-framework building coral taxa, and that these species are now major regional carbonate producers. However, because these species typically have lower calcification rates, continued transitions to states dominated by non-framework building coral species will further reduce carbonate production rates below 'predecline' levels, resulting in shifts towards negative carbonate budget states and reducing reef growth potential.
Abstract.
Perry C, Steneck RS, Murphy GN, Kench PS, Edinger EN, Smithers SG, Mumby PJ (2015). Regional-scale dominance of non-framework building corals on Caribbean reefs affects carbonate production and future reef growth. Global Change Biology, 21, 1153-1164.
Perry CT, Steneck RS, Murphy GN, Kench PS, Edinger EN, Smithers SG, Mumby PJ (2015). Regional-scale dominance of non-framework building corals on Caribbean reefs affects carbonate production and future reef growth.
Glob Chang Biol,
21(3), 1153-1164.
Abstract:
Regional-scale dominance of non-framework building corals on Caribbean reefs affects carbonate production and future reef growth.
Coral cover on Caribbean reefs has declined rapidly since the early 1980's. Diseases have been a major driver, decimating communities of framework building Acropora and Orbicella coral species, and reportedly leading to the emergence of novel coral assemblages often dominated by domed and plating species of the genera Agaricia, Porites and Siderastrea. These corals were not historically important Caribbean framework builders, and typically have much smaller stature and lower calcification rates, fuelling concerns over reef carbonate production and growth potential. Using data from 75 reefs from across the Caribbean we quantify: (i) the magnitude of non-framework building coral dominance throughout the region and (ii) the contribution of these corals to contemporary carbonate production. Our data show that live coral cover averages 18.2% across our sites and coral carbonate production 4.1 kg CaCO3 m(-2) yr(-1). However, non-framework building coral species dominate and are major carbonate producers at a high proportion of sites; they are more abundant than Acropora and Orbicella at 73% of sites; contribute an average 68% of the carbonate produced; and produce more than half the carbonate at 79% of sites. Coral cover and carbonate production rate are strongly correlated but, as relative abundance of non-framework building corals increases, average carbonate production rates decline. Consequently, the use of coral cover as a predictor of carbonate budget status, without species level production rate data, needs to be treated with caution. Our findings provide compelling evidence for the Caribbean-wide dominance of non-framework building coral taxa, and that these species are now major regional carbonate producers. However, because these species typically have lower calcification rates, continued transitions to states dominated by non-framework building coral species will further reduce carbonate production rates below 'predecline' levels, resulting in shifts towards negative carbonate budget states and reducing reef growth potential.
Abstract.
Author URL.
2014
Perry CT, Murphy GN, Kench PS, Edinger EN, Smithers SG, Steneck RS, Mumby PJ (2014). Changing dynamics of Caribbean reef carbonate budgets: emergence of reef bioeroders as critical controls on present and future reef growth potential.
Proceedings. Biological sciences / the Royal Society,
281(1796).
Abstract:
Changing dynamics of Caribbean reef carbonate budgets: emergence of reef bioeroders as critical controls on present and future reef growth potential
© 2014 the Author(s) Published by the Royal Society. All rights reserved.Coral cover has declined rapidly on Caribbean reefs since the early 1980s, reducing carbonate production and reef growth. Using a cross-regional dataset, we show that widespread reductions in bioerosion rates-a key carbonate cycling process-have accompanied carbonate production declines. Bioerosion by parrotfish, urchins, endolithic sponges and microendoliths collectively averages 2 G (where G = kg CaCO3 m(-2) yr(-1)) (range 0.96-3.67 G). This rate is at least 75% lower than that reported from Caribbean reefs prior to their shift towards their present degraded state. Despite chronic overfishing, parrotfish are the dominant bioeroders, but erosion rates are reduced from averages of approximately 4 to 1.6 G. Urchin erosion rates have declined further and are functionally irrelevant to bioerosion on most reefs. These changes demonstrate a fundamental shift in Caribbean reef carbonate budget dynamics. To-date, reduced bioerosion rates have partially offset carbonate production declines, limiting the extent to which more widespread transitions to negative budget states have occurred. However, given the poor prognosis for coral recovery in the Caribbean and reported shifts to coral community states dominated by slower calcifying taxa, a continued transition from production to bioerosion-controlled budget states, which will increasingly threaten reef growth, is predicted.
Abstract.
Perry CT, Murphy GN, Kench PS, Edinger EN, Smithers SG, Steneck RS, Mumby PJ (2014). Changing dynamics of Caribbean reef carbonate budgets: emergence of reef bioeroders as critical controls on present and future reef growth potential.
Proc Biol Sci,
281(1796).
Abstract:
Changing dynamics of Caribbean reef carbonate budgets: emergence of reef bioeroders as critical controls on present and future reef growth potential.
Coral cover has declined rapidly on Caribbean reefs since the early 1980s, reducing carbonate production and reef growth. Using a cross-regional dataset, we show that widespread reductions in bioerosion rates-a key carbonate cycling process-have accompanied carbonate production declines. Bioerosion by parrotfish, urchins, endolithic sponges and microendoliths collectively averages 2 G (where G = kg CaCO3 m(-2) yr(-1)) (range 0.96-3.67 G). This rate is at least 75% lower than that reported from Caribbean reefs prior to their shift towards their present degraded state. Despite chronic overfishing, parrotfish are the dominant bioeroders, but erosion rates are reduced from averages of approximately 4 to 1.6 G. Urchin erosion rates have declined further and are functionally irrelevant to bioerosion on most reefs. These changes demonstrate a fundamental shift in Caribbean reef carbonate budget dynamics. To-date, reduced bioerosion rates have partially offset carbonate production declines, limiting the extent to which more widespread transitions to negative budget states have occurred. However, given the poor prognosis for coral recovery in the Caribbean and reported shifts to coral community states dominated by slower calcifying taxa, a continued transition from production to bioerosion-controlled budget states, which will increasingly threaten reef growth, is predicted.
Abstract.
Author URL.
Perry C, Steneck RS, Murphy GN, Kench PS, Edinger EN, Smithers SG, Mumby PJ (2014). Changing dynamics of Caribbean reef carbonate budgets: emergence of reef bioeroders as critical controls on present and future reef growth potential. Proceedings of the Royal Society of London: Biological Sciences, 281, 2014-2018.
Hepburn L, Blanchon P, Murphy G, Cousins L, Perry C (2014). Community structure and paleoecological implications of calcareous encrusters on artificial substrates across a Mexican reef. Coral Reefs, 34, 189-200.
Roche RC, Perry CT, Smithers SG, Leng MJ, Grove CA, Sloane HJ, Unsworth CE (2014). Mid-Holocene sea surface conditions and riverine influence on the inshore Great Barrier Reef.
Holocene,
24(8), 885-897.
Abstract:
Mid-Holocene sea surface conditions and riverine influence on the inshore Great Barrier Reef
We present measurements of Sr/Ca, δ18O, and spectral luminescence ratios (G/B) from a mid-Holocene Porites sp. microatoll recovered from the nearshore Great Barrier Reef (GBR). These records were used as proxies to reconstruct sea surface temperature (SST), the δ18O of surrounding seawater (δ18Osw), and riverine influence, respectively, and compared with records from a modern Porites sp. microatoll growing in the same environment. Strong riverine influence in the mid-Holocene record is indicated by (1) an increased annual δ18Osw range in the mid-Holocene record, (2) negative peaks in δ18O characteristic of flood events, and (3) a higher G/B luminescence ratio. Seasonal cycles in G/B suggest that humic acid inputs were elevated for a longer portion of the year during the mid-Holocene. The seasonal cycle of δ18Osw peaked earlier in the year in the mid-Holocene record relative to the modern, while mean δ18Osw values from the mid-Holocene record were similar to modern values. These records provide an insight into the oceanographic conditions the nearshore GBR experienced during mid-Holocene climatic shifts and are consistent with a strong Australian-Indonesian Summer Monsoon (AISM) system at ~ 4700 cal. yr BP. © the Author(s) 2014.
Abstract.
Roche RC, Perry C, Smithers SG, Leng MJ, Grove CA, Sloane HJ, Unsworth C (2014). Mid-Holocene sea surface conditions and riverine influence on the inshore Great Barrier Reef. The Holocene: a major interdisciplinary journal focusing on recent environmental change
Salter MA, Perry C, Wilson RW (2014). Size fraction analysis of fish-derived carbonates in shallow sub-tropical marine environments and a potentially unrecognised origin for peloidal carbonates. Sedimentary Geology, 314, 17-30.
Salter MA, Perry CT, Wilson RW (2014). Size fraction analysis of fish-derived carbonates in shallow sub-tropical marine environments and a potentially unrecognised origin for peloidal carbonates.
Sedimentary Geology,
314, 17-30.
Abstract:
Size fraction analysis of fish-derived carbonates in shallow sub-tropical marine environments and a potentially unrecognised origin for peloidal carbonates
Marine bony fish are now known as primary producers of calcium carbonate. Furthermore, within the shallow sub-tropical platform settings of the Bahamas, this production process has been shown to occur at rates relevant to carbonate sediment production budgets. Fish excrete these carbonates as loosely aggregated pellets which, post-excretion, exhibit a range of distinctive crystal morphologies and have mineralogies ranging from low (0-4mol% MgCO3) to high (4-40mol% MgCO3) Mg-calcites, aragonite and amorphous carbonate phases. Here we provide the first quantitative assessment of the size fractions of the carbonates produced by a range of tropical fish species, and document the extent of post-excretion carbonate pellet break down under a range of physical agitation conditions. Specifically, we document the morphologies and size fractions of: i) intact pellets at the point of excretion; ii) intact pellets after agitation in seawater; and iii) the particles released from pellets post-disaggregation. Results indicate that fish-derived pellets initially fall within the very fine to very coarse sand fractions. Exposure to conditions of moderate seawater agitation for 30days results in significant pellet diminution; 66% of initial pellet mass being released as individual particles, whilst 34% is retained as partially intact pellets that are smaller (fine sand-grade) and more rounded than initial pellets. In contrast, pellets exposed to very gently agitated conditions for up to 200days show little change. Where pellet disaggregation does occur, particles are commonly released as individual clay- and silt-grade crystals. However, some morphotypes (e.g. polycrystalline spheres) can be intergrown and are released as strongly cohesive particle clusters falling within the coarse silt to fine sand fractions. Only very vigorous agitation may disaggregate such particles, resulting in the release of their component clay-grade crystals. We conclude that fish-derived carbonates may thus contribute not only to the mud-fraction of marine carbonates, but also to the fine sand fraction as intergrown particles, and to the fine to coarse sand fractions as intact and partially intact pellets. These experimental data indicate that hydrodynamic regimes local to sites of excretion will influence the generation of carbonates with different size fraction ranges. Rapid pellet disaggregation is more likely in high energy settings, hypothesised to result in redistribution of liberated mud-grade particles to lower energy platform-top settings and/or off-platform. In contrast, pellets excreted in lower energy settings are more likely to be preserved intact, and are thus proposed as a previously unrecognised source of pelletal and peloidal carbonate sediments. •Break-up of carbonate pellets produced by marine bony fish is investigated. •Pellets can remain intact and may contribute to sedimentary pellets and peloids. •Rapid pellet break-up releases component particles in agitated settings. •Particle size ranges from clay to fine sand grade: different depositional fates. •Relevant to surface sediments in shallow sub-tropical marine provinces.
Abstract.
Berkeley A, Perry C, Smithers SG, Hoon SH (2014). Towards a formal description of foraminiferal assemblage formation in near shore environments: qualitative and quantitative concepts. Marine Micropalaeontology, 112, 27-38.
2013
Gulliver P, Palmer S, Perry C, Smithers S (2013). Are coral clasts from a turbid near-shore reef environment a suitable material for radiocarbon analysis?.
Radiocarbon,
55(2-3), 624-630.
Abstract:
Are coral clasts from a turbid near-shore reef environment a suitable material for radiocarbon analysis?
Use of coral skeletons to determine growth histories of reefs situated in warm, clear tropical waters is well established. Recently, however, there has been increasing awareness of the significance of reefs occurring in environments that are considered as marginal for coral growth, such as turbid inshore settings characterized by episodes of elevated turbidity, low light penetration, and periodic sediment burial. While these conditions are generally considered as limiting for coral growth, coral reefs in these settings can exhibit high live coral cover and species diversity, and thus can be both ecologically and geologically significant. Turbid-zone reefs are also commonly concentrated along eroding shorelines with many analogues to erosional shorelines developed during the Holocene transgression. A growing number of studies of these previously undocumented reefs reveal that the reef deposits are detrital in nature, comprising a framework dominated by reef rubble and coral clasts and set within a fine-grained terrigenous sediment matrix. In addition to the recognized effects of diagenesis or algal encrustations on the radiocarbon signature of coral samples, episodic high-energy events may rework sediments and can result in age reversals in the same stratigraphic unit. As in other reef settings, the possibility of such reworking can complicate the reconstruction of turbid-zone reef growth chronologies. In order to test the accuracy of dating coral clasts for developing growth histories of these reef deposits, 5 replicate samples from 5 separate coral clasts were taken from 2 sedimentary units in a core collected from Paluma Shoals, an inshore turbid-zone reef located in Halifax Bay, central Great Barrier Reef, Australia. Results show that where care is taken to screen the clasts for skeletal preservation, primary mineralogical structures, and δ13C values indicative of marine carbonate, then reliable 14C dates can be recovered from individual turbid reef coral samples. In addition, the results show that these individual clasts were deposited coevally. © 2013 by the Arizona Board of Regents on behalf of the University of Arizona.
Abstract.
Kennedy EV, Perry CT, Halloran PR, Iglesias-Prieto R, Schönberg CHL, Wisshak M, Form AU, Carricart-Ganivet JP, Fine M, Eakin CM, et al (2013). Avoiding coral reef functional collapse requires local and global action.
Curr Biol,
23(10), 912-918.
Abstract:
Avoiding coral reef functional collapse requires local and global action.
Coral reefs face multiple anthropogenic threats, from pollution and overfishing to the dual effects of greenhouse gas emissions: rising sea temperature and ocean acidification. While the abundance of coral has declined in recent decades, the implications for humanity are difficult to quantify because they depend on ecosystem function rather than the corals themselves. Most reef functions and ecosystem services are founded on the ability of reefs to maintain their three-dimensional structure through net carbonate accumulation. Coral growth only constitutes part of a reef's carbonate budget; bioerosion processes are influential in determining the balance between net structural growth and disintegration. Here, we combine ecological models with carbonate budgets and drive the dynamics of Caribbean reefs with the latest generation of climate models. Budget reconstructions using documented ecological perturbations drive shallow (6-10 m) Caribbean forereefs toward an increasingly fragile carbonate balance. We then projected carbonate budgets toward 2080 and contrasted the benefits of local conservation and global action on climate change. Local management of fisheries (specifically, no-take marine reserves) and the watershed can delay reef loss by at least a decade under "business-as-usual" rises in greenhouse gas emissions. However, local action must be combined with a low-carbon economy to prevent degradation of reef structures and associated ecosystem services.
Abstract.
Author URL.
Browne NK, Smithers SG, Perry CT (2013). Carbonate and terrigenous sediment budgets for two inshore turbid reefs on the central Great Barrier Reef. Marine Geology, 346, 101-123.
Perry CT, Smithers SG, Gulliver P (2013). Rapid vertical accretion on a ‘young’ shore-detached turbid zone reef: Offshore Paluma Shoals, central Great Barrier Reef, Australia.
Coral Reefs, 1-6.
Author URL.
Perry CT, Kench PS, Smithers SG, Yamano H, O'Leary M, Gulliver P (2013). Time scales and modes of reef lagoon infilling in the maldives and controls on the onset of reef island formation.
Geology,
41(10), 1111-1114.
Abstract:
Time scales and modes of reef lagoon infilling in the maldives and controls on the onset of reef island formation
Faro are annular reefs, with reef fl ats near sea level and lagoons of variable depth, characteristic of both the perimeter and lagoons of Maldivian (Indian Ocean) atolls. Their geomorphic development remains largely unknown, but where faro lagoons (termed velu in Maldivian) have infilled and support reef islands, these provide precious habitable land. Understanding the timing and modes of velu infilling is thus directly relevant to questions about reef island development and vulnerability. Here we use a chronostratigraphic data set obtained from a range of atoll-interior faro with partially to fully filled velu (including those with reef islands) from Baa (South Maalhosmadulu) Atoll, Maldives, to determine time scales and modes of velu infilling, and to identify the temporal and spatial thresholds that control reef island formation. Our data suggest a systematic relationship between faro size, velu infilling, and island development. These relationships likely vary between atolls as a function of atoll lagoon depth, but in Baa Atoll, our data set indicates the following faro-size relationships exist: (1) faros 0.5 km2 but ~1.25 km2 have unfilled (deeper) velu which might only infill over long time scales and which are thus unlikely to support new island initiation. These new observations, when combined with previously published data on Maldivian reef island development, suggest that while the velu of the largest faro are unlikely to fill over the next few centuries (at least), other faro with near-infilled velu may provide important foci for future reef-island building, even under present highstand (and slightly rising) sea levels. © 2013 Geological Society of America.
Abstract.
2012
Browne N, Smithers SG, Perry C, Ridd P (2012). A field based technique for measuring sediment flux on coral reefs: application to turbid reefs on the Great Barrier Reef. Journal of Coastal Research: an international forum for the littoral sciences, in press
Browne N, Smithers SG, Perry C (2012). Coral reefs of the turbid inner Great Barrier Reef: a geological perspective on occurrence, composition and growth. Earth-Science Reviews, in press
Browne NK, Smithers SG, Perry CT (2012). Coral reefs of the turbid inner-shelf of the Great Barrier Reef, Australia: an environmental and geomorphic perspective on their occurrence, composition and growth. Earth-Science Reviews, 115(1-2), 1-20.
Perry C, Edinger EN, Kench PS, Murphy G, Steneck RS, Smithers SG, Mumby PJ (2012). Estimating rates of biologically driven coral reef framework production and erosion: a new census-based carbonate budget methodology and applications to the reefs of Bonaire. Coral Reefs, in press
Perry C, Smithers SG, Gulliver P, Browne N (2012). Evidence of very rapid reef accretion and reef growth under high turbidity and terrigenous sedimentation. Geology (Boulder), 40, 719-722.
Salter MA, Perry CT, Wilson RW (2012). Production of mud-grade carbonates by marine fish: Crystalline products and their sedimentary significance. Sedimentology
Salter MA, Perry C, Wilson RW (2012). Production of mud-grade carbonates by marine fish: crystalline products and their sedimentary significance. Sedimentolology, in press
Browne NK, Smithers SG, Perry CT (2012). Spatial and temporal variations in turbidity on two inshore turbid reefs on the Great Barrier Reef, Australia. Coral Reefs, 32(1), 195-210.
2011
Wilson RW, Reardon EE, Perry CT (2011). A fishy tale: a missing part of the inorganic ocean carbon cycle.
The Biochemist(June), 30-34.
Author URL.
Perry CT, Smithers SG (2011). Cycles of coral reef ‘turn-on’, rapid growth and ‘turn-off’ over the past 8,500 years: a context for understanding modern ecological states and trajectories. Global Change Biology, 17, 76-86.
Perry CT, Salter MA, Harborne AR, Crowley SF, Jelks HJ, Wilson RW (2011). Fish as major carbonate mud producers and missing components of the tropical carbonate factory. Proceedings of the National Academy of Science, 108, 3865-3869.
Perry CT, Salter MA, Harborne AR, Crowley SF, Jelks HL, Wilson RW (2011). Fish as major carbonate mud producers and missing components of the tropical carbonate factory.
Proc Natl Acad Sci U S A,
108(10), 3865-3869.
Abstract:
Fish as major carbonate mud producers and missing components of the tropical carbonate factory.
Carbonate mud is a major constituent of recent marine carbonate sediments and of ancient limestones, which contain unique records of changes in ocean chemistry and climate shifts in the geological past. However, the origin of carbonate mud is controversial and often problematic to resolve. Here we show that tropical marine fish produce and excrete various forms of precipitated (nonskeletal) calcium carbonate from their guts ("low" and "high" Mg-calcite and aragonite), but that very fine-grained (mostly < 2 μm) high Mg-calcite crystallites (i.e. > 4 mole % MgCO(3)) are their dominant excretory product. Crystallites from fish are morphologically diverse and species-specific, but all are unique relative to previously known biogenic and abiotic sources of carbonate within open marine systems. Using site specific fish biomass and carbonate excretion rate data we estimate that fish produce ∼6.1 × 10(6) kg CaCO(3)/year across the Bahamian archipelago, all as mud-grade (the < 63 μm fraction) carbonate and thus as a potential sediment constituent. Estimated contributions from fish to total carbonate mud production average ∼14% overall, and exceed 70% in specific habitats. Critically, we also document the widespread presence of these distinctive fish-derived carbonates in the finest sediment fractions from all habitat types in the Bahamas, demonstrating that these carbonates have direct relevance to contemporary carbonate sediment budgets. Fish thus represent a hitherto unrecognized but significant source of fine-grained carbonate sediment, the discovery of which has direct application to the conceptual ideas of how marine carbonate factories function both today and in the past.
Abstract.
Author URL.
Perry CT, Kench PS, Smithers SG, Riegl BR, Yamano H, O'Leary MJ (2011). Implications of reef ecosystem change for the stability and maintenance of coral reef islands. Global Change Biology, 17, 3679-3696.
Roche R, Perry CT, Johnson KG, Saltana K, Smithers SG, Thompson AA (2011). Mid-Holocene coral community data as a baseline for understanding contemporary reef ecological states. Palaeogeography, Palaeoclimatology, Palaeoecology, 299, 159-167.
Perry CT, Smithers SG, Wassenburg J, Roche R (2011). Recurrent patterns of coral community and sediment facies development through successive phases of Holocene reef growth and decline. Marine Geology, 289, 60-71.
Roche R, Abel RA, Johnson KG, Perry CT (2011). Spatial variation in porosity and skeletal element characteristics in apical tips of the branching coral Acropora pulchra (Brook 1891). Coral Reefs, 30, 195-201.
2010
Perry CT (2010). Carbonate budgets and reef framework accumulation. In (Ed) Encyclopaedia of Modern Coral Reefs, Springer-Verlag, 185-190.
Kench PS, Perry CT, Spencer T (2010). Coral Reefs. In (Ed) Geomorphology and Global Environmental Change: Landscape Scale Implications, Cambridge: Cambridge University Press, 180-213.
Perry CT, Smithers SG (2010). Evidence for the episodic 'turn-on' and ‘turn-off' of turbid-zone, inner-shelf coral reefs during the late Holocene sea-level highstand. Geology, 38, 119-122.
Browne N, Smithers SG, Perry CT (2010). Geomorphology and community structure of Middle Reef, central Great Barrier Reef, Australia: an inner-shelf turbid zone reef subjected to episodic mortality events. Coral Reefs, 26, 683-689.
Perry CT (2010). Holocene high energy window. In Hopley D (Ed) Encyclopaedia of Modern Coral Reefs, Springer-Verlag, 558-561.
O'Leary M, Perry CT (2010). Holocene reef accretion on the Rodrigues carbonate platform: an alternative to the classic ‘bucket-fill’ model. Geology, 38, 855-858.
Palmer SE, Perry CT, Smithers SG, Gulliver P (2010). Internal structure and accretionary history of a Holocene nearshore, turbid-zone coral reef: Paluma Shoals, central Great Barrier Reef, Australia. Marine Geology, 276, 14-29.
Roche R, Abel RA, Johnson KG, Perry CT (2010). Quantification of porosity in Acropora pulchra (Brook 1891) using X-ray micro-computed tomography techniques. Journal of Experimental Marine Biology & Ecology, 396, 1-9.
Berkeley A, Perry CT, Smithers SG (2010). Taphonomic signatures and patterns of test degradation on tropical, intertidal benthic foraminifera. Marine Micropalaeontology, 73, 148-163.
Perry CT (2010). Turbid-zone and terrigenous sediment-influenced reefs. In (Ed) Encyclopaedia of Modern Coral Reefs, Springer-Verlag, 1110-1120.
2009
Berkeley A, Perry CT, Smithers SG, Horton BP, Cundy AB (2009). Foraminiferal biofacies across mangrove-mudflat environments at Cocoa Creek, north Queensland, Australia. Marine Geology, 263, 64-86.
Perry CT, Berkeley A (2009). Intertidal substrate modification as a result of mangrove planting: impacts of introduced mangrove species on sediment microfacies characteristics. Estuarine, Coastal and Shelf Science, 81, 225-237.
Perry CT, Smithers SG, Johnson KG (2009). Long-term coral community records from Lugger Shoal on the terrigenous inner-shelf of the central Great Barrier Reef, Australia. Coral Reefs, 28, 941-948.
Perry CT, Smithers SG (2009). Stabilisation of intertidal cobbles and gravels by Goniastrea aspera: an analogue for substrate colonisation during marine transgressions?. Coral Reefs, 28, 805-806.
O'Leary MJ, Perry CT, Turner J, Beavington-Penney SJ (2009). The significant role of sediment bio-retexturing within a contemporary carbonate
platform system: implications for carbonate microfacies development. Sedimentary Geology, 219, 169-179.
2008
Perry CT, Smithers SG, Palmer SE, Larcombe P, Johnson KG (2008). A 1200 year paleoecological record of coral community development from the terrigenous inner-shelf of the Great Barrier Reef. Geology, 36, 691-694.
Perry CT, Spencer T, Kench PS (2008). Carbonate budgets and reef production states: a geomorphic perspective on the ecological phase-shift concept. Coral Reefs, 27, 853-866.
Perry CT, Berkeley A, Smithers SG (2008). Microfacies Characteristics of a Tropical, Mangrove-Fringed Shoreline, Cleveland Bay, Queensland, Australia: Sedimentary and Taphonomic Controls on Mangrove Facies Development. Journal of Sedimentary Research, 78(2), 77-97.
Perry CT, Berkeley A, Smithers SG (2008). Microfacies characteristics of a tropical, mangrove-fringed shoreline, Cleveland Bay, central Great Barrier Reef, Australia: mangrove sequence development and facies preservation. Journal of Sedimentary Research, 78, 77-97.
Perry CT, Hepburn LJ (2008). Syn-depositional alteration of coral reef framework through bioerosion, encrustation and cementation: taphonomic signatures of reef accretion and reef depositional events. Earth-Science Reviews, 86, 106-144.
Berkeley A, Perry CT, Smithers SG, Horton BP (2008). The spatial and vertical distribution of living (stained) benthic foraminifera from a tropical, intertidal environment, north Queensland, Australia. Marine Micropalaeontology, 69, 240-261.
2007
Berkeley A, Perry CT, Smithers SG, Horton BP, Taylor KG (2007). A review of the ecological and taphonomic controls on foraminiferal assemblage development in intertidal environments. Earth-Science Reviews, 83(3-4), 205-230.
Taylor KG, Perry CT, Greenaway AM, Machent PG (2007). Bacterial iron oxide reduction in a terrigenous sediment-impacted tropical shallow marine carbonate system, north Jamaica. Marine Chemistry, 107(4), 449-463.
2006
Mallela J, Perry CT (2006). Calcium carbonate budgets for two coral reefs affected by different terrestrial runoff regimes, Rio Bueno, Jamaica. Coral Reefs, 26(1), 129-145.
PERRY CT, TAYLOR KG (2006). Inhibition of dissolution within shallow water carbonate sediments: impacts of terrigenous sediment input on syn-depositional carbonate diagenesis. Sedimentology, 53(3), 495-513.
Perry CT, Smithers SG (2006). Taphonomic signatures of turbid-zone reef development: Examples from Paluma Shoals and Lugger Shoal, inshore central Great Barrier Reef, Australia. Palaeogeography, Palaeoclimatology, Palaeoecology, 242(1-2), 1-20.
Perry CT, Taylor KG, Machent PG (2006). Temporal shifts in reef lagoon sediment composition, Discovery Bay, Jamaica. Estuarine, Coastal and Shelf Science, 67(1-2), 133-144.
2005
MACDONALD I, PERRY C, LARCOMBE P (2005). Comment on ?Rivers, runoff, and reefs? by McLaughlin et al. [Global Planetary Change 39 (2003) 191?199]. Global and Planetary Change, 45(4), 333-337.
Perry CT, Beavington-Penney SJ (2005). Epiphytic calcium carbonate production and facies development within sub-tropical seagrass beds, Inhaca Island, Mozambique. Sedimentary Geology, 174(3-4), 161-176.
Perry CT (2005). Morphology and occurrence of rhodoliths in siliciclastic, intertidal environments from a high latitude reef setting, southern Mozambique. Coral Reefs, 24(2), 201-207.
Perry CT (2005). Structure and development of detrital reef deposits in turbid nearshore environments, Inhaca Island, Mozambique. Marine Geology, 214(1-3), 143-161.
