1
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Sommer B, Hodge JM, Lachs L, Cant J, Pandolfi JM, Beger M. Decadal demographic shifts and size-dependent disturbance responses of corals in a subtropical warming hotspot. Sci Rep 2024; 14:6327. [PMID: 38491152 PMCID: PMC10943097 DOI: 10.1038/s41598-024-56890-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Accepted: 03/12/2024] [Indexed: 03/18/2024] Open
Abstract
Long-term demographic studies at biogeographic transition zones can elucidate how body size mediates disturbance responses. Focusing on subtropical reefs in eastern Australia, we examine trends in the size-structure of corals with contrasting life-histories and zoogeographies surrounding the 2016 coral bleaching event (2010-2019) to determine their resilience and recovery capacity. We document demographic shifts, with disproportionate declines in the number of small corals and long-term persistence of larger corals. The incidence of bleaching (Pocillopora, Turbinaria) and partial mortality (Acropora, Pocillopora) increased with coral size, and bleached corals had greater risk of partial mortality. While endemic Pocillopora experienced marked declines, decadal stability of Turbinaria despite bleaching, coupled with abundance increase and bleaching resistance in Acropora indicate remarkable resilience of these taxa in the subtropics. Declines in the number of small corals and variable associations with environmental drivers indicate bottlenecks to recovery mediated by inhibitory effects of thermal extremes for Pocillopora (heat stress) and Acropora (heat and cold stress), and stimulatory effects of chlorophyll-a for Turbinaria. Although our study reveals signs of resilience, it foreshadows the vulnerability of subtropical corals to changing disturbance regimes that include marine heatwaves. Disparity in population dynamics suggest that subtropical reefs are ecologically distinct from tropical coral reefs.
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Affiliation(s)
- Brigitte Sommer
- School of Life and Environmental Science, The University of Sydney, Sydney, NSW, 2006, Australia.
| | - Jessica M Hodge
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
- Maldives Underwater Initiative, Six Senses Laamu, Olhuveli Island, Laamu Atoll, Republic of Maldives
| | - Liam Lachs
- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - James Cant
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
- Centre for Biological Diversity, University of St Andrews, St Andrews, KY16 9TH, Scotland, UK
| | - John M Pandolfi
- School of the Environment, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Maria Beger
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
- Centre for Biodiversity and Conservation Science, School of Biological Sciences, University of Queensland, Brisbane, QLD, 4072, Australia
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2
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Carlson RR, Crowder LB, Martin RE, Asner GP. The effect of reef morphology on coral recruitment at multiple spatial scales. Proc Natl Acad Sci U S A 2024; 121:e2311661121. [PMID: 38190515 PMCID: PMC10823213 DOI: 10.1073/pnas.2311661121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 11/24/2023] [Indexed: 01/10/2024] Open
Abstract
Coral reefs are in decline worldwide, making it increasingly important to promote coral recruitment in new or degraded habitat. Coral reef morphology-the structural form of reef substrate-affects many aspects of reef function, yet the effect of reef morphology on coral recruitment is not well understood. We used structure-from-motion photogrammetry and airborne remote sensing to measure reef morphology (rugosity, curvature, slope, and fractal dimension) across a broad continuum of spatial scales and evaluated the effect of morphology on coral recruitment in three broadcast-spawning genera. We also measured the effect of other environmental and biotic factors such as fish density, adult coral cover, hydrodynamic larval import, and depth on coral recruitment. All variables combined explained 72% of coral recruitment in the study region. Coarse reef rugosity and curvature mapped at ≥2 m spatial resolution-such as large colonies, knolls, and boulders-were positively correlated with coral recruitment, explaining 22% of variation in recruitment. Morphology mapped at finer scales (≤32 cm resolution) was not significant. Hydrodynamic larval import was also positively related to coral recruitment in Porites and Montipora spp., and grazer fish density was linked to significantly lower recruitment in all genera. In addition, grazer density, reef morphology, and hydrodynamic import had differential effects on coral genera, reflecting genus-specific life history traits, and model performance was lower in gonochoric species. Overall, coral reef morphology is a key indicator of recruitment potential that can be detected by remote sensing, allowing potential larval sinks to be identified and factored into restoration actions.
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Affiliation(s)
- Rachel R. Carlson
- Emmett Interdisciplinary Program in Environment and Resources, Doerr School of Sustainability, Stanford University, Stanford, CA94305
- Center for Global Discovery and Conservation Science, Arizona State University, Hilo, HI96720
| | - Larry B. Crowder
- Emmett Interdisciplinary Program in Environment and Resources, Doerr School of Sustainability, Stanford University, Stanford, CA94305
| | - Roberta E. Martin
- Center for Global Discovery and Conservation Science, Arizona State University, Hilo, HI96720
| | - Gregory P. Asner
- Center for Global Discovery and Conservation Science, Arizona State University, Hilo, HI96720
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3
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Benkwitt CE, D'Angelo C, Dunn RE, Gunn RL, Healing S, Mardones ML, Wiedenmann J, Wilson SK, Graham NAJ. Seabirds boost coral reef resilience. SCIENCE ADVANCES 2023; 9:eadj0390. [PMID: 38055814 DOI: 10.1126/sciadv.adj0390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Accepted: 11/03/2023] [Indexed: 12/08/2023]
Abstract
Global climate change threatens tropical coral reefs, yet local management can influence resilience. While increasing anthropogenic nutrients reduce coral resistance and recovery, it is unknown how the loss, or restoration, of natural nutrient flows affects reef recovery. Here, we test how natural seabird-derived nutrient subsidies, which are threatened by invasive rats, influence the mechanisms and patterns of reef recovery following an extreme marine heatwave using multiyear field experiments, repeated surveys, and Bayesian modeling. Corals transplanted from rat to seabird islands quickly assimilated seabird-derived nutrients, fully acclimating to new nutrient conditions within 3 years. Increased seabird-derived nutrients, in turn, caused a doubling of coral growth rates both within individuals and across entire reefs. Seabirds were also associated with faster recovery time of Acropora coral cover (<4 years) and more dynamic recovery trajectories of entire benthic communities. We conclude that restoring seabird populations and associated nutrient pathways may foster greater coral reef resilience through enhanced growth and recovery rates of corals.
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Affiliation(s)
| | - Cecilia D'Angelo
- Coral Reef Laboratory, School of Ocean and Earth Science, University of Southampton, Southampton SO143ZH, UK
| | - Ruth E Dunn
- Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK
- The Lyell Centre, Heriot-Watt University, Edinburgh EH14 4AS, UK
| | - Rachel L Gunn
- Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK
- Animal Evolutionary Ecology, Institute of Evolution and Ecology, University of Tübingen, Auf Der Morgenstelle 28, 72076 Tübingen, Germany
| | - Samuel Healing
- Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK
| | - M Loreto Mardones
- Coral Reef Laboratory, School of Ocean and Earth Science, University of Southampton, Southampton SO143ZH, UK
| | - Joerg Wiedenmann
- Coral Reef Laboratory, School of Ocean and Earth Science, University of Southampton, Southampton SO143ZH, UK
| | - Shaun K Wilson
- Australian Institute of Marine Science, Indian Ocean Marine Research Centre, Crawley, WA 6009, Australia
- University of Western Australia, UWA Oceans Institute, Crawley, WA 6009, Australia
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4
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Randrianarivo M, Botosoamananto RL, Guilhaumon F, Penin L, Todinanahary G, Adjeroud M. Effects of Madagascar marine reserves on juvenile and adult coral abundance, and the implication for population regulation. MARINE ENVIRONMENTAL RESEARCH 2023; 190:106080. [PMID: 37422994 DOI: 10.1016/j.marenvres.2023.106080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 06/30/2023] [Accepted: 07/05/2023] [Indexed: 07/11/2023]
Abstract
Recruitment is a critical component in the dynamics of coral assemblages, and a key question is to determine the degree to which spatial heterogeneity of adults is influenced by pre-vs. post-settlement processes. We analyzed the density of juvenile and adult corals among 18 stations located at three regions around Madagascar, and examined the effects of Marine Protected Areas (MPAs). Our survey did not detect a positive effect of MPAs on juveniles, except for Porites at the study scale. The MPA effect was more pronounced for adults, notably for Acropora, Montipora, Seriatopora, and Porites at the regional scale. For most dominant genera, densities of juveniles and adults were positively correlated at the study scale, and at least at one of the three regions. These outcomes suggest recruitment-limitation relationships for several coral taxa, although differences in post-settlement events may be sufficiently strong to distort the pattern established at settlement for other populations. The modest benefits of MPAs on the density of juvenile corals demonstrated here argue in favor of strengthening conservation measures more specifically focused to protect recruitment processes.
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Affiliation(s)
- Mahery Randrianarivo
- Institut Halieutique et des Sciences Marines, Université de Toliara, Toliara, Madagascar; ENTROPIE, Université de La Réunion, IRD, CNRS, IFREMER, Université de la Nouvelle-Calédonie, La Réunion, France
| | - Radonirina Lebely Botosoamananto
- Institut Halieutique et des Sciences Marines, Université de Toliara, Toliara, Madagascar; ENTROPIE, Université de La Réunion, IRD, CNRS, IFREMER, Université de la Nouvelle-Calédonie, La Réunion, France
| | - François Guilhaumon
- ENTROPIE, Université de La Réunion, IRD, CNRS, IFREMER, Université de la Nouvelle-Calédonie, La Réunion, France
| | - Lucie Penin
- ENTROPIE, Université de La Réunion, IRD, CNRS, IFREMER, Université de la Nouvelle-Calédonie, La Réunion, France; Laboratoire d'Excellence "CORAIL", Paris, France
| | - Gildas Todinanahary
- Institut Halieutique et des Sciences Marines, Université de Toliara, Toliara, Madagascar
| | - Mehdi Adjeroud
- ENTROPIE, IRD, Université de la Réunion, CNRS, IFREMER, Université de la Nouvelle-Calédonie, Perpignan, France; Laboratoire d'Excellence "CORAIL", Paris, France; PSL Université Paris, UAR 3278, CRIOBE EPHE-UPVD-CNRS, Perpignan, France.
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5
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Hazraty-Kari S, Morita M, Tavakoli-Kolour P, Nakamura T, Harii S. Reactions of juvenile coral to three years of consecutive thermal stress. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 863:161227. [PMID: 36586691 DOI: 10.1016/j.scitotenv.2022.161227] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 12/06/2022] [Accepted: 12/23/2022] [Indexed: 06/17/2023]
Abstract
As global temperatures continue to rise, corals are being exposed to increasing heat stress throughout their early life stages; however, the impact of this phenomenon is poorly understood. We exposed the reef-building coral Acropora tenuis juveniles to ∼26-28 °C (control) and ∼ 31 °C (heat stress) for one week per year over three consecutive years. In the first year of heat stress, >96 % of juveniles survived despite symbiotic algal densities in juvenile corals declining. In comparison, survival rates in the third year of heat stress declined to 50 %. Survival rates under natural conditions after stress also gradually decreased in the stressed groups. The rate in the reduction of survivorship was prominent in the consecutive thermally stressed groups (juveniles stressed twice in two years). Symbiotic algal density and photosynthetic activity (Fv/Fm) also declined in stressed juvenile groups. However, heat stress did not significantly affect the growth of juveniles. In the third year of heat stress, temperature negatively affected the physiology of juveniles in terms of survivorship, brightness (an indicator of bleaching), symbiotic algal density, and photosynthetic efficiency. Stress across consecutive years appeared to cause the survivorship of juvenile corals to decline, with three years of stress contributing to the severe decline of a reef. In conclusion, A. tenuis juveniles are not able to acclimatize to heat stress, with successive heat waves of <7 days in the summer potentially negatively affecting resilience.
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Affiliation(s)
- Sanaz Hazraty-Kari
- Graduate School of Engineering and Science, University of the Ryukyus, Okinawa, Japan.
| | - Masaya Morita
- Sesoko Station, Tropical Biosphere Research Center, University of the Ryukyus, Okinawa, Japan
| | | | - Takashi Nakamura
- Graduate School of Engineering and Science, University of the Ryukyus, Okinawa, Japan; Sesoko Station, Tropical Biosphere Research Center, University of the Ryukyus, Okinawa, Japan
| | - Saki Harii
- Sesoko Station, Tropical Biosphere Research Center, University of the Ryukyus, Okinawa, Japan.
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6
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Hadi TA, Utama RS, Arfianti T. Species richness and the dynamics of coral cover in Bangka Belitung Islands, Indonesia. PeerJ 2023; 11:e14625. [PMID: 36860768 PMCID: PMC9969856 DOI: 10.7717/peerj.14625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 12/02/2022] [Indexed: 03/03/2023] Open
Abstract
Pressures on the world's tropical coral reefs that threaten their existence have been reported worldwide due to many stressors. Loss of coral cover and declines in coral richness are two of the most common changes often reported in coral reefs. However, a precise estimate of species richness and the coral cover dynamics for most Indonesian regions, particularly in the Bangka Belitung Islands, have been poorly documented. Annual monitoring data from 2015 to 2018 at 11 fixed sites in the Bangka Belitung Islands using the photo quadrat transect method identified 342 coral species from 63 genera. Of these, 231 species (>65%) were rare or uncommon, occurring in <40% of all sites. The species richness of hard corals was categorized as moderate compared to other studies in Indonesia, averaging 53 species across sites and years, and there was an increasing number of sites with high species richness. The percent cover of live and dead hard corals was greater than other benthic and substrate categories in all sites; revealing a live-dead hard corals pattern with dead coral cover averaged 12% higher than live hard coral across the years, but they did not show a significant difference (P > 0.05). There was a slightly increasing trend in hard coral cover in ten out of 11 sites in 2018, indicating the reefs are in a recovery process. The results support the need to identify recovering or stable areas despite apparent anthropogenic and natural variations recently. This vital information is essential for early detection and preparation for management strategies in the current context of climate change and for ensuring future coral reef survival.
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Affiliation(s)
- Tri Aryono Hadi
- Research Center for Oceanography - National Research and Innovation Agency, North Jakarta, Jakarta, Indonesia
| | - Rizkie Satriya Utama
- Research Center for Oceanography - National Research and Innovation Agency, North Jakarta, Jakarta, Indonesia
| | - Tri Arfianti
- Research Center for Biosystematics and Evolution - National Research and Innovation Agency, Cibinong, West Java, Indonesia
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7
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McWilliam M, Dornelas M, Álvarez-Noriega M, Baird AH, Connolly SR, Madin JS. Net effects of life-history traits explain persistent differences in abundance among similar species. Ecology 2023; 104:e3863. [PMID: 36056537 DOI: 10.1002/ecy.3863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 06/22/2022] [Accepted: 07/18/2022] [Indexed: 02/01/2023]
Abstract
Life-history traits are promising tools to predict species commonness and rarity because they influence a population's fitness in a given environment. Yet, species with similar traits can have vastly different abundances, challenging the prospect of robust trait-based predictions. Using long-term demographic monitoring, we show that coral populations with similar morphological and life-history traits show persistent (decade-long) differences in abundance. Morphological groups predicted species positions along two, well known life-history axes (the fast-slow continuum and size-specific fecundity). However, integral projection models revealed that density-independent population growth (λ) was more variable within morphological groups, and was consistently higher in dominant species relative to rare species. Within-group λ differences projected large abundance differences among similar species in short timeframes, and were generated by small but compounding variation in growth, survival, and reproduction. Our study shows that easily measured morphological traits predict demographic strategies, yet small life-history differences can accumulate into large differences in λ and abundance among similar species. Quantifying the net effects of multiple traits on population dynamics is therefore essential to anticipate species commonness and rarity.
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Affiliation(s)
- Mike McWilliam
- Hawai'i Institute of Marine Biology, University of Hawai'i at Mānoa, Kāne'ohe, Hawai'i, USA
| | - Maria Dornelas
- Centre for Biological Diversity, Scottish Oceans Institute, University of St Andrews, St Andrews, UK
| | - Mariana Álvarez-Noriega
- Centre for Geometric Biology, School of Biological Sciences, Monash University, Melbourne, Victoria, Australia
| | - Andrew H Baird
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Queensland, Australia
| | | | - Joshua S Madin
- Hawai'i Institute of Marine Biology, University of Hawai'i at Mānoa, Kāne'ohe, Hawai'i, USA
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8
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Adaptations by the coral Acropora tenuis confer resilience to future thermal stress. Commun Biol 2022; 5:1371. [PMID: 36517561 PMCID: PMC9751277 DOI: 10.1038/s42003-022-04309-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Accepted: 11/28/2022] [Indexed: 12/15/2022] Open
Abstract
Elevated temperatures cause coral bleaching and reef degradation. However, coral may have strategies to survive by reproducing more heat-tolerable larvae. We examine the direct and carryover effects of thermal stress on fecundity and fitness in the reef-building coral Acropora tenuis. Fragments from the same colony are subjected to control temperature (~27.5 °C) or heat stress (~31 °C) for ten days. We then examine the fecundity of adults (egg number and size) and the thermal tolerance of larvae and recruits (survival rates, growth, and size). The stressed fragments show a trade-off in egg production, an increase in egg number but a decrease in size. In addition, larvae and recruits from the stressed colony show marginally higher survival rates in the higher water temperature but do not differ in the control condition. Therefore, corals produce more heat-resistant larvae and recruits after they experience heat stress, which may improve coral reef resilience.
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9
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Sarribouette L, Pedersen NE, Edwards CB, Sandin SA. Post-settlement demographics of reef building corals suggest prolonged recruitment bottlenecks. Oecologia 2022; 199:387-396. [PMID: 35661251 PMCID: PMC9226083 DOI: 10.1007/s00442-022-05196-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 05/21/2022] [Indexed: 11/24/2022]
Abstract
For many organisms, early life stages experience significantly higher rates of mortality relative to adults. However, tracking early life stage individuals through time in natural settings is difficult, limiting our understanding of the duration of these ‘mortality bottlenecks’, and the time required for survivorship to match that of adults. Here, we track a cohort of juvenile corals (1–5 cm maximum diameter) from 12 taxa at a remote atoll in the Central Pacific from 2013 to 2017 and describe patterns of annual survivorship. Of the 537 juveniles initially detected, 219 (41%) were alive 4 years later, 163 (30%) died via complete loss of live tissue from the skeleton, and the remaining 155 (29%) died via dislodgement. The differing mortality patterns suggest that habitat characteristics, as well as species-specific features, may influence early life stage survival. Across most taxa, survival fit a logistic model, reaching > 90% annual survival within 4 years. These data suggest that mortality bottlenecks characteristic of ‘recruitment’ extend up to 5 years after individuals can be visually detected. Ultimately, replenishment of adult coral populations via sexual reproduction is needed to maintain both coral cover and genetic diversity. This study provides key insights into the dynamics and time scales that characterize these critical early life stages.
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Affiliation(s)
| | - Nicole E Pedersen
- Scripps Institution of Oceanography, UC San Diego, La Jolla, CA, 92093-0202, USA
| | - Clinton B Edwards
- Scripps Institution of Oceanography, UC San Diego, La Jolla, CA, 92093-0202, USA
| | - Stuart A Sandin
- Scripps Institution of Oceanography, UC San Diego, La Jolla, CA, 92093-0202, USA.
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10
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Doropoulos C, Gómez-Lemos LA, Salee K, McLaughlin MJ, Tebben J, Van Koningsveld M, Feng M, Babcock RC. Limitations to coral recovery along an environmental stress gradient. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2022; 32:e2558. [PMID: 35112758 DOI: 10.1002/eap.2558] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 11/09/2021] [Accepted: 11/16/2021] [Indexed: 06/14/2023]
Abstract
Positive feedbacks driving habitat-forming species recovery and population growth are often lost as ecosystems degrade. For such systems, identifying mechanisms that limit the re-establishment of critical positive feedbacks is key to facilitating recovery. Theory predicts the primary drivers limiting system recovery shift from biological to physical as abiotic stress increases, but recent work has demonstrated that this seldom happens. We combined field and laboratory experiments to identify variation in limitations to coral recovery along an environmental stress gradient at Ningaloo Reef and Exmouth Gulf in northwest Australia. Many reefs in the region are coral depauperate due to recent cyclones and thermal stress. In general, recovery trajectories are prolonged due to limited coral recruitment. Consistent with theory, clearer water reefs under low thermal stress appear limited by biological interactions: competition with turf algae caused high mortality of newly settled corals and upright macroalgal stands drove mortality in transplanted juvenile corals. Laboratory experiments showed a positive relationship between crustose coralline algae cover and coral settlement, but only in the absence of sedimentation. Contrary to expectation, coral recovery does not appear limited by the survival or growth of recruits on turbid reefs under higher thermal stress, but to exceptionally low larval supply. Laboratory experiments showed that larval survival and settlement are unaffected by seawater quality across the study region. Rather, connectivity models predicted that many of the more turbid reefs in the Gulf are predominantly self seeded, receiving limited supply under degraded reef states. Overall, we find that the influence of oceanography can overwhelm the influences of physical and biological interactions on recovery potential at locations where environmental stressors are high, whereas populations in relatively benign physical conditions are predominantly structured by local ecological drivers. Such context-dependent information can help guide expectations and assist managers in optimizing strategies for spatial conservation planning for system recovery.
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Affiliation(s)
| | - Luis A Gómez-Lemos
- Universidad Nacional de Colombia - Sede de La Paz - Escuela de Pregrados, La Paz, Colombia
| | - Kinam Salee
- CSIRO Oceans and Atmosphere, St Lucia, Queensland, Australia
| | | | - Jan Tebben
- Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
| | - Mark Van Koningsveld
- Van Oord Dredging and Marine Contractors B.V., Rotterdam, The Netherlands
- Ports and Waterways, Delft University of Technology, Delft, The Netherlands
| | - Ming Feng
- CSIRO Oceans and Atmosphere, St Lucia, Queensland, Australia
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11
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Matsuda SB, Chakravarti LJ, Cunning R, Huffmyer AS, Nelson CE, Gates RD, van Oppen MJH. Temperature-mediated acquisition of rare heterologous symbionts promotes survival of coral larvae under ocean warming. GLOBAL CHANGE BIOLOGY 2022; 28:2006-2025. [PMID: 34957651 PMCID: PMC9303745 DOI: 10.1111/gcb.16057] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 12/04/2021] [Accepted: 12/07/2021] [Indexed: 06/14/2023]
Abstract
Reef-building corals form nutritional symbioses with endosymbiotic dinoflagellates (Symbiodiniaceae), a relationship that facilitates the ecological success of coral reefs. These symbionts are mostly acquired anew each generation from the environment during early life stages ("horizontal transmission"). Symbiodiniaceae species exhibit trait variation that directly impacts the health and performance of the coral host under ocean warming. Here, we test the capacity for larvae of a horizontally transmitting coral, Acropora tenuis, to establish symbioses with Symbiodiniaceae species in four genera that have varying thermal thresholds (the common symbiont genera, Cladocopium and Durusdinium, and the less common Fugacium and Gerakladium). Over a 2-week period in January 2018, a series of both no-choice and four-way choice experiments were conducted at three temperatures (27, 30, and 31°C). Symbiont acquisition success and cell proliferation were measured in individual larvae. Larvae successfully acquired and maintained symbionts of all four genera in no-choice experiments, and >80% of larvae were infected with at least three genera when offered a four-way choice. Unexpectedly, Gerakladium symbionts increased in dominance over time, and at high temperatures outcompeted Durusdinium, which is regarded as thermally tolerant. Although Fugacium displayed the highest thermal tolerance in culture and reached similar cell densities to the other three symbionts at 31°C, it remained a background symbiont in choice experiments, suggesting host preference for other symbiont species. Larval survivorship at 1 week was highest in larvae associated with Gerakladium and Fugacium symbionts at 27 and 30°C, however at 31°C, mortality was similar for all treatments. We hypothesize that symbionts that are currently rare in corals (e.g., Gerakladium) may become more common and widespread in early life stages under climate warming. Uptake of such symbionts may function as a survival strategy in the wild, and has implications for reef restoration practices that use sexually produced coral stock.
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Affiliation(s)
- Shayle B. Matsuda
- Hawai‘i Institute of Marine BiologyUniversity of Hawai‘i at MānoaKāne‘oheHawai‘iUSA
| | | | - Ross Cunning
- Daniel P. Haerther Center for Conservation and ResearchJohn G. Shedd AquariumChicagoIllinoisUSA
| | - Ariana S. Huffmyer
- Department of Biological SciencesUniversity of Rhode IslandKingstonRhode IslandUSA
| | - Craig E. Nelson
- Daniel K. Inouye Center for Microbial Oceanography: Research and EducationDepartment of Oceanography and Sea Grant College ProgramUniversity of Hawai‘i at MānoaHonoluluHawai‘iUSA
| | - Ruth D. Gates
- Hawai‘i Institute of Marine BiologyUniversity of Hawai‘i at MānoaKāne‘oheHawai‘iUSA
| | - Madeleine J. H. van Oppen
- Australian Institute of Marine ScienceTownsvilleQueenslandAustralia
- School of BioSciencesThe University of MelbourneParkvilleVictoriaAustralia
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12
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Bozec Y, Hock K, Mason RAB, Baird ME, Castro‐Sanguino C, Condie SA, Puotinen M, Thompson A, Mumby PJ. Cumulative impacts across Australia’s Great Barrier Reef: a mechanistic evaluation. ECOL MONOGR 2021. [DOI: 10.1002/ecm.1494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Yves‐Marie Bozec
- Marine Spatial Ecology Lab School of Biological Sciences & ARC Centre of Excellence for Coral Reef Studies University of Queensland St Lucia Queensland 4072 Australia
| | - Karlo Hock
- Marine Spatial Ecology Lab School of Biological Sciences & ARC Centre of Excellence for Coral Reef Studies University of Queensland St Lucia Queensland 4072 Australia
| | - Robert A. B. Mason
- Marine Spatial Ecology Lab School of Biological Sciences & ARC Centre of Excellence for Coral Reef Studies University of Queensland St Lucia Queensland 4072 Australia
| | - Mark E. Baird
- CSIRO Oceans and Atmosphere Hobart Tasmania 7001 Australia
| | - Carolina Castro‐Sanguino
- Marine Spatial Ecology Lab School of Biological Sciences & ARC Centre of Excellence for Coral Reef Studies University of Queensland St Lucia Queensland 4072 Australia
| | | | - Marji Puotinen
- Australian Institute of Marine Science & Indian Ocean Marine Research Centre Crawley Western Australia 6009 Australia
| | - Angus Thompson
- Australian Institute of Marine Science Townsville Queensland 4810 Australia
| | - Peter J. Mumby
- Marine Spatial Ecology Lab School of Biological Sciences & ARC Centre of Excellence for Coral Reef Studies University of Queensland St Lucia Queensland 4072 Australia
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13
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Koester A, Ford AK, Ferse SCA, Migani V, Bunbury N, Sanchez C, Wild C. First insights into coral recruit and juvenile abundances at remote Aldabra Atoll, Seychelles. PLoS One 2021; 16:e0260516. [PMID: 34874982 PMCID: PMC8651144 DOI: 10.1371/journal.pone.0260516] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 11/12/2021] [Indexed: 11/19/2022] Open
Abstract
Coral recruitment and successive growth are essential for post-disturbance reef recovery. As coral recruit and juvenile abundances vary across locations and under different environmental regimes, their assessment at remote, undisturbed reefs improves our understanding of early life stage dynamics of corals. Here, we first explored changes in coral juvenile abundance across three locations (lagoon, seaward west and east) at remote Aldabra Atoll (Seychelles) between 2015 and 2019, which spanned the 2015/16 global coral bleaching event. Secondly, we measured variation in coral recruit abundance on settlement tiles from two sites (lagoon, seaward reef) during August 2018-August 2019. Juvenile abundance decreased from 14.1 ± 1.2 to 7.4 ± 0.5 colonies m-2 (mean ± SE) during 2015-2016 and increased to 22.4 ± 1.2 colonies m-2 during 2016-2019. Whilst juvenile abundance increased two- to three-fold at the lagoonal and seaward western sites during 2016-2018 (from 7.7-8.3 to 17.3-24.7 colonies m-2), increases at the seaward eastern sites occurred later (2018-2019; from 5.8-6.9 to 16.6-24.1 colonies m-2). The composition of coral recruits on settlement tiles was dominated by Pocilloporidae (64-92% of all recruits), and recruit abundance was 7- to 47-fold higher inside than outside the lagoon. Recruit abundance was highest in October-December 2018 (2164 ± 453 recruits m-2) and lowest in June-August 2019 (240 ± 98 recruits m-2). As Acroporid recruit abundance corresponded to this trend, the results suggest that broadcast spawning occurred during October-December, when water temperature increased from 26 to 29°C. This study provides the first published record on coral recruit abundance in the Seychelles Outer Islands, indicates a rapid (2-3 years) increase of juvenile corals following a bleaching event, and provides crucial baseline data for future research on reef resilience and connectivity within the region.
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Affiliation(s)
- Anna Koester
- Marine Ecology Department, Faculty of Biology & Chemistry, University of Bremen, Bremen, Germany
- Seychelles Islands Foundation, Victoria, Mahé, Seychelles
| | - Amanda K. Ford
- School of Agriculture, Geography, Environment, Ocean and Natural Sciences, University of the South Pacific, Suva, Fiji
| | - Sebastian C. A. Ferse
- Marine Ecology Department, Faculty of Biology & Chemistry, University of Bremen, Bremen, Germany
- Leibniz Centre for Tropical Marine Research, Bremen, Germany
| | - Valentina Migani
- Institute for Ecology, Faculty of Biology & Chemistry, University of Bremen, Bremen, Germany
| | - Nancy Bunbury
- Seychelles Islands Foundation, Victoria, Mahé, Seychelles
- Centre for Ecology and Conservation, University of Exeter, Cornwall Campus, Penryn, United Kingdom
| | - Cheryl Sanchez
- Seychelles Islands Foundation, Victoria, Mahé, Seychelles
- Department of Biology, University of Pisa, Pisa, Italy
| | - Christian Wild
- Marine Ecology Department, Faculty of Biology & Chemistry, University of Bremen, Bremen, Germany
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Cheung MWM, Hock K, Skirving W, Mumby PJ. Cumulative bleaching undermines systemic resilience of the Great Barrier Reef. Curr Biol 2021; 31:5385-5392.e4. [PMID: 34739820 DOI: 10.1016/j.cub.2021.09.078] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 08/23/2021] [Accepted: 09/28/2021] [Indexed: 10/19/2022]
Abstract
Climate change and ENSO have triggered five mass coral bleaching events on Australia's Great Barrier Reef (GBR), three of which occurred in the last 5 years.1-5 Here, we explore the cumulative nature of recent impacts and how they fragment the reef's connectivity. The coverage and intensity of thermal stress have increased steadily over time. Cumulative bleaching in 2016, 2017, and 2020 is predicted to have reduced systemic larval supply by 26%, 50%, and 71%, respectively. Larval disruption is patchy and can guide interventions. The majority of severely bleached reefs (75%) are predicted to have experienced an 80%-100% loss of larval supply. Yet restoration would not be cost-effective in the 2% of such reefs (∼30) that still experience high larval supply. Managing such climate change impacts will benefit from emerging theory on the facilitation of genetic adaptation,6,7 which requires the existence of regions with predictably high or low thermal stress. We find that a third of reefs constitute warm spots that have consistently experienced bleaching stress. Moreover, 13% of the GBR are potential refugia that avoid significant warming more than expected by chance, with a modest proportion (14%) within highly protected areas. Coral connectivity is likely to become increasingly disrupted given the predicted escalation of climate-driven disturbances,8 but the existence of thermal refugia, potentially capable of delivering larvae to 58% of the GBR, may provide pockets of systemic resilience in the near-term. Theories of conservation planning for climate change will need to consider a shifting portfolio of thermal environments over time.
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Affiliation(s)
- Mandy W M Cheung
- Marine Spatial Ecology Lab, School of Biological Sciences, The University of Queensland, St Lucia, QLD 4072, Australia; Australian Research Council Centre of Excellence for Coral Reef Studies, The University of Queensland, St Lucia, QLD 4072, Australia.
| | - Karlo Hock
- Marine Spatial Ecology Lab, School of Biological Sciences, The University of Queensland, St Lucia, QLD 4072, Australia; Australian Research Council Centre of Excellence for Coral Reef Studies, The University of Queensland, St Lucia, QLD 4072, Australia
| | - William Skirving
- Coral Reef Watch, U.S. National Oceanic and Atmospheric Administration, College Park, MD 20740, USA; ReefSense Pty Ltd, Cranbrook, QLD 4814, Australia
| | - Peter J Mumby
- Marine Spatial Ecology Lab, School of Biological Sciences, The University of Queensland, St Lucia, QLD 4072, Australia; Australian Research Council Centre of Excellence for Coral Reef Studies, The University of Queensland, St Lucia, QLD 4072, Australia.
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15
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Gouezo M, Fabricius K, Harrison P, Golbuu Y, Doropoulos C. Optimizing coral reef recovery with context-specific management actions at prioritized reefs. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 295:113209. [PMID: 34346392 DOI: 10.1016/j.jenvman.2021.113209] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 06/06/2021] [Accepted: 06/30/2021] [Indexed: 06/13/2023]
Abstract
Assisting the natural recovery of coral reefs through local management actions is needed in response to increasing ecosystem disturbances in the Anthropocene. There is growing evidence that commonly used resilience-based passive management approaches may not be sufficient to maintain coral reef key functions. We synthesize and discuss advances in coral reef recovery research, and its application to coral reef conservation and restoration practices. We then present a framework to guide the decision-making of reef managers, scientists and other stakeholders, to best support reef recovery after a disturbance. The overall aim of this management framework is to catalyse reef recovery, to minimize recovery times, and to limit the need for ongoing management interventions into the future. Our framework includes two main stages: first, a prioritization method for assessment following a large-scale disturbance, which is based on a reef's social-ecological values, and on a classification of the likelihood of recovery or succession resulting in degraded, novel, hybrid or historical states. Second, a flow chart to assist with determining management actions for highly valued reefs. Potential actions are chosen based on the ecological attributes of the disturbed reef, defined during ecological assessments. Depending on the context, management actions may include (1) substrata rehabilitation actions to facilitate natural coral recruitment, (2) repopulating actions using active restoration techniques, (3) resilience-based management actions and (4) monitoring coral recruitment and growth to assess the effectiveness of management interventions. We illustrate the proposed decision framework with a case study of typhoon-damaged eastern outer reefs in Palau, Micronesia. The decisions made following this framework lead to the conclusion that some reefs may not return to their historical state for many decades. However, if motivation and funds are available, new management approaches can be explored to assist coral reefs at valued locations to return to a functional state providing key ecosystem services.
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Affiliation(s)
- Marine Gouezo
- Palau International Coral Reef Center, PO Box 7086, Koror, Palau; Marine Ecology Research Centre, Southern Cross University, PO Box 157, Lismore, NSW 2480, Australia.
| | - Katharina Fabricius
- Australian Institute of Marine Science, PMB 3, Townsville, QLD 4810, Australia.
| | - Peter Harrison
- Marine Ecology Research Centre, Southern Cross University, PO Box 157, Lismore, NSW 2480, Australia.
| | - Yimnang Golbuu
- Palau International Coral Reef Center, PO Box 7086, Koror, Palau.
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16
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Thomson DP, Babcock RC, Evans RD, Feng M, Moustaka M, Orr M, Slawinski D, Wilson SK, Hoey AS. Coral larval recruitment in north-western Australia predicted by regional and local conditions. MARINE ENVIRONMENTAL RESEARCH 2021; 168:105318. [PMID: 33853011 DOI: 10.1016/j.marenvres.2021.105318] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 03/14/2021] [Accepted: 03/22/2021] [Indexed: 06/12/2023]
Abstract
Understanding ecological processes that shape contemporary and future communities facilitates knowledge-based environmental management. In marine ecosystems, one of the most important processes is the supply of new recruits into a population. Here, we investigated spatiotemporal variability in coral recruitment at 15 reefs throughout the Dampier Archipelago, north-western Australia between 2015 and 2017 and identified the best environmental predictors for coral recruitment patterns over this period. Large differences in recruitment were observed among years with the average density of recruits increasing by 375% from 0.017 recruits cm-2 in 2015 to 0.059 recruits cm-2 in 2017. Despite differences in recruitment among years, the rank order of coral recruit density among reefs remained similar among years, suggesting that spatial variation in recruitment within the Dampier Archipelago is partly deterministic and predictable. The density of coral recruits was best explained by percent cover of live corals at both local (within 5 m) and meso-scales (within 15 km), water turbidity and an oceanographic model that predicted larval dispersal. The highest density of coral recruits (~0.13 recruits cm-2 or 37 recruits per tile) occurred on reefs within sub-regions (15 km) with greater than 35% coral cover, low to moderate turbidity (KD490 < 0.2) and moderate to high modelled predictions of larval dispersal. Our results demonstrate that broad-scale larval dispersal models, when combined with local metrics of percent hard coral cover and water turbidity, can reliably predict the relative abundance of coral recruits over large geographical areas and thus can identify hotspots of recruit abundance and potential recovery following environmental disturbances; information that is essential for effective management of coral reefs.
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Affiliation(s)
- Damian P Thomson
- CSIRO Oceans & Atmosphere, Indian Ocean Marine Research Centre, University of Western Australia, M097, 35 Stirling Highway, Crawley, WA, 6009, Australia; Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Queensland, 4811, Australia.
| | - Russell C Babcock
- CSIRO Oceans and Atmosphere, GPO Box 2583, Brisbane, Queensland, 4001, Australia
| | - Richard D Evans
- Marine Science Program, Biodiversity and Conservation Science, Department of Biodiversity, Conservation and Attractions, Kensington, W.A, 6151, Australia; Oceans Institute, University of Western Australia, Crawley, WA, 6009, Australia
| | - Ming Feng
- CSIRO Oceans & Atmosphere, Indian Ocean Marine Research Centre, University of Western Australia, M097, 35 Stirling Highway, Crawley, WA, 6009, Australia
| | - Molly Moustaka
- Marine Science Program, Biodiversity and Conservation Science, Department of Biodiversity, Conservation and Attractions, Kensington, W.A, 6151, Australia
| | - Melanie Orr
- CSIRO Oceans & Atmosphere, Indian Ocean Marine Research Centre, University of Western Australia, M097, 35 Stirling Highway, Crawley, WA, 6009, Australia
| | - Dirk Slawinski
- CSIRO Oceans & Atmosphere, Indian Ocean Marine Research Centre, University of Western Australia, M097, 35 Stirling Highway, Crawley, WA, 6009, Australia
| | - Shaun K Wilson
- Marine Science Program, Biodiversity and Conservation Science, Department of Biodiversity, Conservation and Attractions, Kensington, W.A, 6151, Australia; Oceans Institute, University of Western Australia, Crawley, WA, 6009, Australia
| | - Andrew S Hoey
- Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Queensland, 4811, Australia
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17
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Huffmyer AS, Johnson CJ, Epps AM, Lemus JD, Gates RD. Feeding and thermal conditioning enhance coral temperature tolerance in juvenile Pocillopora acuta. ROYAL SOCIETY OPEN SCIENCE 2021; 8:210644. [PMID: 34084554 PMCID: PMC8150050 DOI: 10.1098/rsos.210644] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 05/06/2021] [Indexed: 05/13/2023]
Abstract
Scleractinian corals form the foundation of coral reefs by acquiring autotrophic nutrition from photosynthetic endosymbionts (Symbiodiniaceae) and use feeding to obtain additional nutrition, especially when the symbiosis is compromised (i.e. bleaching). Juvenile corals are vulnerable to stress due to low energetic reserves and high demand for growth, which is compounded when additional stressors occur. Therefore, conditions that favour energy acquisition and storage may enhance survival under stressful conditions. To investigate the influence of feeding on thermal tolerance, we exposed Pocillopora acuta juveniles to temperature (ambient, 27.4°C versus cool, 25.9°C) and feeding treatments (fed versus unfed) for 30 days post-settlement and monitored growth and physiology, followed by tracking survival under thermal stress. Feeding increased growth and resulted in thicker tissues and elevated symbiont fluorescence. Under high-temperature stress (31-60 days post-settlement; ca 30.1°C), corals that were fed and previously exposed to cool temperature had 33% higher survival than other treatment groups. These corals demonstrated reduced symbiont fluorescence, which may have provided protective effects under thermal stress. These results highlight that the impacts of feeding on coral physiology and stress tolerance are dependent on temperature and as oceans continue to warm, early life stages may experience shifts in feeding strategies to survive.
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Affiliation(s)
- Ariana S. Huffmyer
- Hawai‘i Institute of Marine Biology, University of Hawai‘i at Mānoa, Kāne‘ohe, HI 96744, USA
- Department of Biological Sciences, University of Rhode Island, Kingston, RI 02881, USA
| | - Colton J. Johnson
- Hawai‘i Institute of Marine Biology, University of Hawai‘i at Mānoa, Kāne‘ohe, HI 96744, USA
- Department of Biology, San Diego State University, San Diego, CA 92182, USA
| | - Ashleigh M. Epps
- Hawai‘i Institute of Marine Biology, University of Hawai‘i at Mānoa, Kāne‘ohe, HI 96744, USA
- Department of Life Sciences, Texas A&M University-Corpus Christi, Corpus Christi, TX 78412, USA
| | - Judith D. Lemus
- Hawai‘i Institute of Marine Biology, University of Hawai‘i at Mānoa, Kāne‘ohe, HI 96744, USA
| | - Ruth D. Gates
- Hawai‘i Institute of Marine Biology, University of Hawai‘i at Mānoa, Kāne‘ohe, HI 96744, USA
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18
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Shlesinger T, van Woesik R. Different population trajectories of two reef-building corals with similar life-history traits. J Anim Ecol 2021; 90:1379-1389. [PMID: 33666226 PMCID: PMC8252767 DOI: 10.1111/1365-2656.13463] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 02/26/2021] [Indexed: 01/01/2023]
Abstract
Increases in the frequency and intensity of acute and chronic disturbances are causing declines of coral reefs world‐wide. Although quantifying the responses of corals to acute disturbances is well documented, detecting subtle responses of coral populations to chronic disturbances is less common, but can also result in altered population and community structures. We investigated the population dynamics of two key reef‐building Merulinid coral species, Dipsastraea favus and Platygyra lamellina, with similar life‐history traits, in the Gulf of Eilat and Aqaba, Red Sea from 2015 to 2018, to assess potential differences in their population trajectories. Demographic processes, which included rates of survival, growth, reproduction and recruitment were used to parametrize integral projection models and estimate population growth rates and the likely population trajectories of both coral species. The survival and reproduction rates of both D. favus and P. lamellina were positively related to coral colony size, and elasticity analyses showed that large colonies most influenced population dynamics. Although both species have similar life‐history traits and growth morphologies and are generally regarded as ‘stress‐tolerant’, the populations showed contrasting trajectories—D. favus appears to be increasing whereas P. lamellina appears to be decreasing. As many corals have long‐life expectancies, the process of local and regional decline might be subtle and slow. Ecological assessments based on total living coral coverage, morphological groups or functional traits might overlook subtle, species‐specific trends. However, demographic approaches capable of detecting subtle species‐specific population changes can augment ecological studies and provide valuable early warning signs of decline before major coral loss becomes evident.
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Affiliation(s)
- Tom Shlesinger
- Institute for Global Ecology, Florida Institute of Technology, Melbourne, FL, USA
| | - Robert van Woesik
- Institute for Global Ecology, Florida Institute of Technology, Melbourne, FL, USA
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19
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Abstract
Abstract
Modern-day Indo-Pacific coral reefs are characterized by rapid recovery driven by pulses of coral recruitment, but Caribbean reefs exhibit low rates of recruitment and poor recovery following a wide range of disturbance events. The contrasting evolutionary history of coral taxa offers key insight into biogeographic patterns of coral resilience. Following the closure of the Isthmus of Panama approximately 2.8 million years ago, widespread extinction of Caribbean corals led to an evolutionary bottleneck that favored large and long-lived species with a relatively high reliance on asexual versus sexual reproduction. In contrast, adaptive radiation led to the evolution of superrecruiting tabular, digitate, and corymbose corals that drive the rapid recovery of modern-day Indo-Pacific reefs following disturbance. The dominance of branching growth forms and evolutionary absence of superrecruiting growth forms throughout the entire evolutionary history of the Caribbean (approximately 38 million years ago to present) may explain the exceptionally high recruitment rates on modern-day Indo-Pacific reefs and low historical recruitment on Caribbean reefs. The evolutionary history of the Caribbean coral reef-building taxa implies that, even with a reversal of ecosystem state, widespread recovery of Caribbean reefs may be limited.
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Affiliation(s)
- George Roff
- School of Biological Sciences, University of Queensland, in St. Lucia, Australia
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20
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Da-Anoy JP, Cabaitan PC, Conaco C. Warm temperature alters the chemical cue preference of Acropora tenuis and Heliopora coerulea larvae. MARINE POLLUTION BULLETIN 2020; 161:111755. [PMID: 33120034 DOI: 10.1016/j.marpolbul.2020.111755] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Revised: 10/01/2020] [Accepted: 10/07/2020] [Indexed: 05/19/2023]
Abstract
Larvae released into the water column rely on chemical cues from the benthos for successful settlement. However, larval preference for substrates may be affected by rising seawater temperature brought about by global climate change. In this study, we examined the effect of elevated temperature on chemical cue preference by larvae of the scleractinian coral, Acropora tenuis, and the octocoral, Heliopora coerulea, collected from northwestern Philippines. At ambient temperature (28 °C), both H. coerulea and A. tenuis larvae showed preference for substrates containing either crustose coralline algae or crude ethanolic extracts from conspecific or congeneric corals. In contrast, at higher temperature (30 °C), greater preference was shown for substrates containing the crude extract from conspecific or congeneric corals. These results demonstrate that elevated temperature can change larval substrate preference, which will have downstream impacts on crucial biological processes, such as larval settlement and recruitment.
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Affiliation(s)
- Jeric P Da-Anoy
- Marine Science Institute, University of the Philippines, Diliman, Quezon City 1101, Philippines
| | - Patrick C Cabaitan
- Marine Science Institute, University of the Philippines, Diliman, Quezon City 1101, Philippines
| | - Cecilia Conaco
- Marine Science Institute, University of the Philippines, Diliman, Quezon City 1101, Philippines.
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21
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Sandin SA, Edwards CB, Pedersen NE, Petrovic V, Pavoni G, Alcantar E, Chancellor KS, Fox MD, Stallings B, Sullivan CJ, Rotjan RD, Ponchio F, Zgliczynski BJ. Considering the rates of growth in two taxa of coral across Pacific islands. ADVANCES IN MARINE BIOLOGY 2020; 87:167-191. [PMID: 33293010 DOI: 10.1016/bs.amb.2020.08.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Reef-building coral taxa demonstrate considerable flexibility and diversity in reproduction and growth mechanisms. Corals take advantage of this flexibility to increase or decrease size through clonal expansion and loss of live tissue area (i.e. via reproduction and mortality of constituent polyps). The biological lability of reef-building corals may be expected to map onto varying patterns of demography across environmental contexts which can contribute to geographic variation in population dynamics. Here we explore the patterns of growth of two common coral taxa, corymbose Pocillopora and massive Porites, across seven islands in the central and south Pacific. The islands span a natural gradient of environmental conditions, including a range of pelagic primary production, a metric linked to the relative availability of inorganic nutrients and heterotrophic resources for mixotrophic corals, and sea surface temperature and thermal histories. Over a multi-year sampling interval, most coral colonies experienced positive growth (greater planar area of live tissue in second relative to first time point), though the distributions of growth varied across islands. Island-level median growth did not relate simply to estimated pelagic primary productivity or temperature. However, at locations that experienced an extreme warm-water event during the sampling interval, most Porites colonies experienced net losses of live tissue and nearly all Pocillopora colonies experienced complete mortality. While descriptive statistics of demographics offer valuable insights into trends and variability in colony change through time, simplified models predicting growth patterns based on summarized oceanographic metrics appear inadequate for robust demographic prediction. We propose that the complexity of life history strategies among colonial reef-building corals introduces unique demographic flexibility for colonies to respond to a wide breadth of environmental conditions.
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Affiliation(s)
- Stuart A Sandin
- Scripps Institution of Oceanography, UC San Diego, La Jolla, CA, United States.
| | - Clinton B Edwards
- Scripps Institution of Oceanography, UC San Diego, La Jolla, CA, United States
| | - Nicole E Pedersen
- Scripps Institution of Oceanography, UC San Diego, La Jolla, CA, United States
| | - Vid Petrovic
- Department of Computer Science and Engineering, UC San Diego, La Jolla, CA, United States
| | - Gaia Pavoni
- Visual Computing Lab, Istituto di Scienza e Tecnologie dell'Informazione "A. Faedo", Consiglio Nazionale delle Ricerche, Pisa, Italy
| | - Esmeralda Alcantar
- Scripps Institution of Oceanography, UC San Diego, La Jolla, CA, United States
| | | | - Michael D Fox
- Woods Hole Oceanographic Institution, Woods Hole, MA, United States
| | - Brenna Stallings
- Department of Biology, Boston University, Boston, MA, United States
| | | | - Randi D Rotjan
- Department of Biology, Boston University, Boston, MA, United States
| | - Federico Ponchio
- Visual Computing Lab, Istituto di Scienza e Tecnologie dell'Informazione "A. Faedo", Consiglio Nazionale delle Ricerche, Pisa, Italy
| | - Brian J Zgliczynski
- Scripps Institution of Oceanography, UC San Diego, La Jolla, CA, United States
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22
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Horoszowski-Fridman YB, Izhaki I, Rinkevich B. Long-term heightened larval production in nursery-bred coral transplants. Basic Appl Ecol 2020. [DOI: 10.1016/j.baae.2020.05.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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23
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Evans RD, Wilson SK, Fisher R, Ryan NM, Babcock R, Blakeway D, Bond T, Dorji P, Dufois F, Fearns P, Lowe RJ, Stoddart J, Thomson DP. Early recovery dynamics of turbid coral reefs after recurring bleaching events. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2020; 268:110666. [PMID: 32510431 DOI: 10.1016/j.jenvman.2020.110666] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 04/22/2020] [Accepted: 04/26/2020] [Indexed: 06/11/2023]
Abstract
The worlds' coral reefs are declining due to the combined effects of natural disturbances and anthropogenic pressures including thermal coral bleaching associated with global climate change. Nearshore corals are receiving increased anthropogenic stress from coastal development and nutrient run-off. Considering forecast increases in global temperatures, greater understanding of drivers of recovery on nearshore coral reefs following widespread bleaching events is required to inform management of local stressors. The west Pilbara coral reefs, with cross-shelf turbidity gradients coupled with a large nearby dredging program and recent history of repeated coral bleaching due to heat stress, represent an opportune location to study recovery from multiple disturbances. Mean coral cover at west Pilbara reefs was monitored from 2009 to 2018 and declined from 45% in 2009 to 5% in 2014 following three heat waves. Recruitment and juvenile abundance of corals were monitored from 2014 to 2018 and were combined with biological and physical data to identify which variables enhanced or hindered early-stage coral recovery of all hard corals and separately for the acroporids, the genera principally responsible for recovery in the short-term (<7 years). From 2014 to 2018, coral cover increased from 5 to 10% but recovery varied widely among sites (0-13%). Hard coral cover typically recovered most at shallower sites that had higher abundance of herbivorous fish, less macroalgae, and lower turbidity. Similarly, acroporid corals recovered most at sites with lower turbidity and macroalgal cover. Juvenile acroporid densities were a good indicator of recovery at least two years after they were recorded. However, recruitment to settlement tiles was not a good predictor of total coral or acroporid recovery. This study shows that coral recovery can be slower in areas of high turbidity and the rate may be reduced by local pressures, such as dredging. Management should focus on improving or maintaining local water quality to increase the likelihood of coral recovery under climate stress. Further, in turbid environments, juvenile coral density predicts early coral recovery better than recruits on tiles and may be a more cost-effective technique for monitoring recovery potential.
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Affiliation(s)
- Richard D Evans
- Department of Biodiversity, Conservation and Attractions, Kensington, W.A, 6151, Australia; Oceans Institute, The University of Western Australia, 35 Stirling Hwy, Perth, WA, 6009, Australia.
| | - Shaun K Wilson
- Department of Biodiversity, Conservation and Attractions, Kensington, W.A, 6151, Australia; Oceans Institute, The University of Western Australia, 35 Stirling Hwy, Perth, WA, 6009, Australia
| | - Rebecca Fisher
- Oceans Institute, The University of Western Australia, 35 Stirling Hwy, Perth, WA, 6009, Australia; Australian Institute of Marine Science, Indian Ocean Marine Research Centre, Perth, WA, 6009, Australia
| | - Nicole M Ryan
- Australian Institute of Marine Science, Indian Ocean Marine Research Centre, Perth, WA, 6009, Australia
| | - Russ Babcock
- CSIRO Oceans & Atmosphere, Indian Ocean Marine Research Centre, Perth, WA, 6009, Australia
| | | | - Todd Bond
- Oceans Institute, The University of Western Australia, 35 Stirling Hwy, Perth, WA, 6009, Australia; School of Biological Science, The University of Western Australia, 35 Stirling Hwy, Perth, WA, 6009, Australia
| | - Passang Dorji
- Remote Sensing and Satellite Research Group, Department of Imaging and Applied Physics, Curtin University, Bentley, WA, 6102, Australia
| | - Francois Dufois
- IFREMER, DYNECO/DHYSED, ZI Pointe du Diable, 29280, Plouzané, France
| | - Peter Fearns
- Remote Sensing and Satellite Research Group, Department of Imaging and Applied Physics, Curtin University, Bentley, WA, 6102, Australia
| | - Ryan J Lowe
- School of Biological Science, The University of Western Australia, 35 Stirling Hwy, Perth, WA, 6009, Australia; ARC Centre of Excellence for Coral Reef Studies, The University of Western Australia, 35 Stirling Hwy, Perth, WA, 6009, Australia
| | - Jim Stoddart
- Oceans Institute, The University of Western Australia, 35 Stirling Hwy, Perth, WA, 6009, Australia; MScience Pty Ltd, Perth, WA, Australia
| | - Damian P Thomson
- CSIRO Oceans & Atmosphere, Indian Ocean Marine Research Centre, Perth, WA, 6009, Australia
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Carturan BS, Pither J, Maréchal JP, Bradshaw CJA, Parrott L. Combining agent-based, trait-based and demographic approaches to model coral-community dynamics. eLife 2020; 9:e55993. [PMID: 32701058 PMCID: PMC7473774 DOI: 10.7554/elife.55993] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 07/23/2020] [Indexed: 11/26/2022] Open
Abstract
The complexity of coral-reef ecosystems makes it challenging to predict their dynamics and resilience under future disturbance regimes. Models for coral-reef dynamics do not adequately account for the high functional diversity exhibited by corals. Models that are ecologically and mechanistically detailed are therefore required to simulate the ecological processes driving coral reef dynamics. Here, we describe a novel model that includes processes at different spatial scales, and the contribution of species' functional diversity to benthic-community dynamics. We calibrated and validated the model to reproduce observed dynamics using empirical data from Caribbean reefs. The model exhibits realistic community dynamics, and individual population dynamics are ecologically plausible. A global sensitivity analysis revealed that the number of larvae produced locally, and interaction-induced reductions in growth rate are the parameters with the largest influence on community dynamics. The model provides a platform for virtual experiments to explore diversity-functioning relationships in coral reefs.
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Affiliation(s)
| | - Jason Pither
- Department of Biology, University of British ColumbiaKelownaCanada
- Institute for Biodiversity, Resilience, and Ecosystem Services, University of British ColumbiaKelownaCanada
- Department of Earth, Environmental and Geographic Sciences, University of British ColumbiaKelownaCanada
| | | | - Corey JA Bradshaw
- Global Ecology, College of Science and Engineering, Flinders UniversityAdelaideAustralia
| | - Lael Parrott
- Department of Biology, University of British ColumbiaKelownaCanada
- Institute for Biodiversity, Resilience, and Ecosystem Services, University of British ColumbiaKelownaCanada
- Department of Earth, Environmental and Geographic Sciences, University of British ColumbiaKelownaCanada
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Lam VYY, Doropoulos C, Bozec YM, Mumby PJ. Resilience Concepts and Their Application to Coral Reefs. Front Ecol Evol 2020. [DOI: 10.3389/fevo.2020.00049] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Gouezo M, Golbuu Y, Fabricius K, Olsudong D, Mereb G, Nestor V, Wolanski E, Harrison P, Doropoulos C. Drivers of recovery and reassembly of coral reef communities. Proc Biol Sci 2020; 286:20182908. [PMID: 30963834 DOI: 10.1098/rspb.2018.2908] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Understanding processes that drive community recovery are needed to predict ecosystem trajectories and manage for impacts under increasing global threats. Yet, the quantification of community recovery in coral reefs has been challenging owing to a paucity of long-term ecological data and high frequency of disturbances. Here we investigate community re-assembly and the bio-physical drivers that determine the capacity of coral reefs to recover following the 1998 bleaching event, using long-term monitoring data across four habitats in Palau. Our study documents that the time needed for coral reefs to recover from bleaching disturbance to coral-dominated state in disturbance-free regimes is at least 9-12 years. Importantly, we show that reefs in two habitats achieve relative stability to a climax community state within that time frame. We then investigated the direct and indirect effects of drivers on the rate of recovery of four dominant coral groups using a structural equation modelling approach. While the rates of recovery differed among coral groups, we found that larval connectivity and juvenile coral density were prominent drivers of recovery for fast growing Acropora but not for the other three groups. Competitive algae and parrotfish had negative and positive effects on coral recovery in general, whereas wave exposure had variable effects related to coral morphology. Overall, the time needed for community re-assembly is habitat specific and drivers of recovery are taxa specific, considerations that require incorporation into planning for ecosystem management under climate change.
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Affiliation(s)
- Marine Gouezo
- 1 Palau International Coral Reef Center , PO Box 7086, Koror , Palau.,2 Marine Ecology Research Centre, Southern Cross University , PO Box 157, Lismore, New South Wales 2480 , Australia
| | - Yimnang Golbuu
- 1 Palau International Coral Reef Center , PO Box 7086, Koror , Palau
| | - Katharina Fabricius
- 3 Australian Institute of Marine Science , PMB 3, Townsville, Queensland 4810 , Australia
| | - Dawnette Olsudong
- 1 Palau International Coral Reef Center , PO Box 7086, Koror , Palau
| | - Geory Mereb
- 1 Palau International Coral Reef Center , PO Box 7086, Koror , Palau
| | - Victor Nestor
- 1 Palau International Coral Reef Center , PO Box 7086, Koror , Palau
| | - Eric Wolanski
- 4 TropWATER and College of Marine and Environmental Sciences, James Cook University , Townsville, Queensland , Australia
| | - Peter Harrison
- 2 Marine Ecology Research Centre, Southern Cross University , PO Box 157, Lismore, New South Wales 2480 , Australia
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Relative roles of biological and physical processes influencing coral recruitment during the lag phase of reef community recovery. Sci Rep 2020; 10:2471. [PMID: 32051446 PMCID: PMC7015914 DOI: 10.1038/s41598-020-59111-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Accepted: 01/19/2020] [Indexed: 11/09/2022] Open
Abstract
Following disturbances, corals recolonize space through the process of recruitment consisting of the three phases of propagule supply, settlement, and post-settlement survival. Yet, each phase is influenced by biophysical factors, leading to recruitment success variability through space. To resolve the relative contributions of biophysical factors on coral recruitment, the recovery of a 150 km long coral reefs in Palau was investigated after severe typhoon disturbances. Overall, we found that benthic organisms had a relatively weak interactive influence on larval settlement rates at the scale of individual tiles, with negative effects mainly exerted from high wave exposure for Acropora corals. In contrast, juvenile coral densities were well predicted by biophysical drivers, through both direct and indirect pathways. High densities of Acropora and Poritidae juveniles were directly explained by the availability of substrata free from space competitors. Juvenile Montipora were found in higher densities where coralline algae coverage was high, which occurred at reefs with high wave exposure, while high densities of juvenile Pocilloporidae occurred on structurally complex reefs with high biomass of bioeroder fish. Our findings demonstrate that strengths of biophysical interactions were taxon-specific and had cascading effects on coral recruitment, which need consideration for predicting reef recovery and conservation strategies.
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Assessing the Resilience Potential of Inshore and Offshore Coral Communities in the Western Gulf of Thailand. JOURNAL OF MARINE SCIENCE AND ENGINEERING 2019. [DOI: 10.3390/jmse7110408] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Coral reefs in the Gulf of Thailand have experienced severe coral bleaching events and anthropogenic disturbances during the last two decades. This study assessed the resilience potential of coral communities at Ko Losin offshore reef sites and Mu Ko Chumphon nearshore coral reefs, in the south of Thailand, by conducting field surveys on the live coral cover, hard substratum composition and diversity and density of juvenile corals. Most study sites had higher percentages of live coral cover compared to dead coral cover. Some inshore and offshore reef sites showed low resilience to coral bleaching events. The total densities of juvenile corals at the study sites were in the range of 0.89–3.73 colonies/m2. The density of the juvenile corals at most reef sites was not dependent on the live coral cover of adult colonies in a reef, particularly for the Acropora communities. We suggest that Ko Losin should be established as a marine protected area, and Mu Ko Chumphon National Park should implement its management plans properly to enhance coral recovery and promote marine ecotourism. Other measures, such as shading, should be also applied at some coral reefs during bleaching periods.
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Spatial Patterns and Short-term Changes of Coral Assemblages Along a Cross-shelf Gradient in the Southwestern Lagoon of New Caledonia. DIVERSITY-BASEL 2019. [DOI: 10.3390/d11020021] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Coral reef assemblages generally form gradients of spatial structures which are governed by a variety of interacting physical and biological processes that vary in intensity, frequency, and spatial scale. Assessing the structure of contemporary reef assemblages may help to understand future changes and to identify appropriate conservation actions. The spatial distribution and interannual variability (from 2006 to 2008) of coral assemblages were investigated at 10 stations in the southwestern lagoon of New Caledonia, and the strength of the cross-shelf gradient was evaluated. Coral cover, generic richness, and abundance of adult and juvenile assemblages were highly variable within and among the three major reef habitats (fringing, mid-shelf, and barrier reefs). Abundance increased with distance from shore, whereas generic richness and cover were not correlated with shelf position. Assemblage composition was generally related to habitat, even though some mid-shelf and fringing reef assemblages resembled those observed on other habitats. A significant correlation between juvenile and adult distributions was recorded, suggesting that adult assemblages are partly controlled by the short-term history of recruitment patterns. The interannual variation of coral assemblages was far less pronounced, with significant changes only detected at some mid-shelf and barrier reefs, for a few genera characterised by high turn-over.
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Doropoulos C, Elzinga J, ter Hofstede R, van Koningsveld M, Babcock RC. Optimizing industrial-scale coral reef restoration: comparing harvesting wild coral spawn slicks and transplanting gravid adult colonies. Restor Ecol 2019. [DOI: 10.1111/rec.12918] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
| | - Jesper Elzinga
- Van Oord Dredging and Marine Contractors B.V.; 3063 NH Rotterdam The Netherlands
| | - Remment ter Hofstede
- Van Oord Dredging and Marine Contractors B.V.; 3063 NH Rotterdam The Netherlands
| | - Mark van Koningsveld
- Van Oord Dredging and Marine Contractors B.V.; 3063 NH Rotterdam The Netherlands
- Ports and Waterways; Delft University of Technology; 2638 CN Delft The Netherlands
| | - Russell C. Babcock
- Commonwealth Scientific and Industrial Research Organisation; St Lucia 4067 Australia
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31
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Punongbayan AT. Markov chain analysis of sessile community dynamics in a degraded Philippine reef to support restoration of coral populations. POPUL ECOL 2019. [DOI: 10.1002/1438-390x.1009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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32
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Chase TJ, Pratchett MS, Frank GE, Hoogenboom MO. Coral-dwelling fish moderate bleaching susceptibility of coral hosts. PLoS One 2018; 13:e0208545. [PMID: 30550591 PMCID: PMC6294555 DOI: 10.1371/journal.pone.0208545] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Accepted: 11/19/2018] [Indexed: 12/05/2022] Open
Abstract
Global environmental change has the potential to disrupt well established species interactions, with impacts on nutrient cycling and ecosystem function. On coral reefs, fish living within the branches of coral colonies can promote coral performance, and it has been hypothesized that the enhanced water flow and nutrients provided by fish to corals could ameliorate coral bleaching. The aim of this study was to evaluate the influence of small, aggregating damselfish on the health of their host corals (physiology, recovery, and survival) before, during, and after a thermal-bleaching event. When comparing coral colonies with and without fish, those with resident fish exhibited higher Symbiodinium densities and chlorophyll in both field and experimentally-induced bleaching conditions, and higher protein concentrations in field colonies. Additionally, colonies with damselfish in aquaria exhibited both higher photosynthetic efficiency (FV/FM) during bleaching stress and post-bleaching recovery, compared to uninhabited colonies. These results demonstrate that symbiotic damselfishes, and the services they provide, translate into measureable impacts on coral tissue, and can influence coral bleaching susceptibility/resilience and recovery. By mediating how external abiotic stressors influence coral colony health, damselfish can affect the functional responses of these interspecific interactions in a warming ocean.
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Affiliation(s)
- T. J. Chase
- Marine Biology and Aquaculture, College of Science and Engineering, James Cook University, Townsville QLD, Australia
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville QLD, Australia
- * E-mail:
| | - M. S. Pratchett
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville QLD, Australia
| | - G. E. Frank
- Marine Biology and Aquaculture, College of Science and Engineering, James Cook University, Townsville QLD, Australia
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville QLD, Australia
| | - M. O. Hoogenboom
- Marine Biology and Aquaculture, College of Science and Engineering, James Cook University, Townsville QLD, Australia
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville QLD, Australia
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33
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Lam VYY, Chaloupka M, Thompson A, Doropoulos C, Mumby PJ. Acute drivers influence recent inshore Great Barrier Reef dynamics. Proc Biol Sci 2018; 285:rspb.2018.2063. [PMID: 30404884 DOI: 10.1098/rspb.2018.2063] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Accepted: 10/12/2018] [Indexed: 11/12/2022] Open
Abstract
Understanding the dynamics of habitat-forming organisms is fundamental to managing natural ecosystems. Most studies of coral reef dynamics have focused on clear-water systems though corals inhabit many turbid regions. Here, we illustrate the key drivers of an inshore coral reef ecosystem using 10 years of biological, environmental, and disturbance data. Tropical cyclones, crown-of-thorns starfish, and coral bleaching are recognized as the major drivers of coral loss at mid- and offshore reefs along the Great Barrier Reef (GBR). In comparison, little is known about what drives temporal trends at inshore reefs closer to major anthropogenic stress. We assessed coral cover dynamics using state-space models within six major inshore GBR catchments. An overall decline was detected in nearly half (46%) of the 15 reefs at two depths (30 sites), while the rest exhibited fluctuating (23%), static (17%), or positive (13%) trends. Inshore reefs responded similarly to their offshore counterparts, where contemporary trends were predominantly influenced by acute disturbance events. Storms emerged as the major driver affecting the inshore GBR, with the effects of other drivers such as disease, juvenile coral density, and macroalgal and turf per cent cover varying from one catchment to another. Flooding was also associated with negative trends in live coral cover in two southern catchments, but the mechanism remains unclear as it is not reflected in available metrics of water quality and may act through indirect pathways.
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Affiliation(s)
- Vivian Y Y Lam
- Marine Spatial Ecology Lab, School of Biological Sciences, The University of Queensland, St. Lucia, Queensland, Australia .,Australian Research Council Centre of Excellence for Coral Reef Studies, St. Lucia, Queensland, Australia
| | - Milani Chaloupka
- Marine Spatial Ecology Lab, School of Biological Sciences, The University of Queensland, St. Lucia, Queensland, Australia.,Ecological Modelling Services Pty Ltd, The University of Queensland, Queensland, Australia
| | - Angus Thompson
- Australian Institute of Marine Science, Townsville, Queensland, Australia
| | - Christopher Doropoulos
- Marine Spatial Ecology Lab, School of Biological Sciences, The University of Queensland, St. Lucia, Queensland, Australia.,CSIRO Oceans and Atmosphere, St. Lucia, Queensland, Australia
| | - Peter J Mumby
- Marine Spatial Ecology Lab, School of Biological Sciences, The University of Queensland, St. Lucia, Queensland, Australia .,Australian Research Council Centre of Excellence for Coral Reef Studies, St. Lucia, Queensland, Australia
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34
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Ortiz JC, Wolff NH, Anthony KRN, Devlin M, Lewis S, Mumby PJ. Impaired recovery of the Great Barrier Reef under cumulative stress. SCIENCE ADVANCES 2018; 4:eaar6127. [PMID: 30035217 PMCID: PMC6051737 DOI: 10.1126/sciadv.aar6127] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 06/12/2018] [Indexed: 05/06/2023]
Abstract
Corals of the Great Barrier Reef (GBR) have declined over the past 30 years. While reef state depends on the balance between disturbance and recovery, most studies have focused on the effects of disturbance on reef decline. We show that coral recovery rates across the GBR declined by an average of 84% between 1992 and 2010. Recovery was variable: Some key coral types had close to zero recovery by the end of that period, whereas some reefs exhibited high recovery. Our results indicate that coral recovery is sensitive to chronic but manageable pressures, and is suppressed for several years following acute disturbances. Loss of recovery capacity was partly explained by the cumulative effects of chronic pressures including water quality, warming, and sublethal effects of acute disturbances (cyclones, outbreaks of crown-of-thorns starfish, and coral bleaching). Modeled projections indicate that recovery rates can respond rapidly to reductions in acute and chronic stressors, a result that is consistent with fast recovery observed on some reefs in the central and southern GBR since the end of the study period. A combination of local management actions to reduce chronic disturbances and global action to limit the effect of climate change is urgently required to sustain GBR coral cover and diversity.
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Affiliation(s)
- Juan-Carlos Ortiz
- Marine Spatial Ecology Lab, School of Biological Sciences, University of Queensland, St Lucia, Queensland 4072, Australia
- Australian Research Council Centre of Excellence for Coral Reef Studies, University of Queensland, St Lucia, Queensland 4072, Australia
- Corresponding author. (J.-C.O.); (N.H.W.); (P.J.M.)
| | - Nicholas H. Wolff
- Marine Spatial Ecology Lab, School of Biological Sciences, University of Queensland, St Lucia, Queensland 4072, Australia
- Global Science, The Nature Conservancy, Brunswick, ME 04011, USA
- Australian Institute of Marine Science, PMB3, Townsville, Queensland 4810, Australia
- Corresponding author. (J.-C.O.); (N.H.W.); (P.J.M.)
| | - Kenneth R. N. Anthony
- Australian Research Council Centre of Excellence for Coral Reef Studies, University of Queensland, St Lucia, Queensland 4072, Australia
| | - Michelle Devlin
- Centre for Environment, Fisheries and Aquaculture Science, Lowestoft NR33 0HT, UK
| | - Stephen Lewis
- Catchment to Reef Research Group, Centre for Tropical Water and Aquatic Ecosystem Research, James Cook University, Townsville, Queensland 4811, Australia
| | - Peter J. Mumby
- Marine Spatial Ecology Lab, School of Biological Sciences, University of Queensland, St Lucia, Queensland 4072, Australia
- Global Science, The Nature Conservancy, Brunswick, ME 04011, USA
- Corresponding author. (J.-C.O.); (N.H.W.); (P.J.M.)
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35
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Adjeroud M, Kayal M, Iborra-Cantonnet C, Vercelloni J, Bosserelle P, Liao V, Chancerelle Y, Claudet J, Penin L. Recovery of coral assemblages despite acute and recurrent disturbances on a South Central Pacific reef. Sci Rep 2018; 8:9680. [PMID: 29946062 PMCID: PMC6018695 DOI: 10.1038/s41598-018-27891-3] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 06/01/2018] [Indexed: 11/08/2022] Open
Abstract
Coral reefs are increasingly threatened by various types of disturbances, and their recovery is challenged by accelerating, human-induced environmental changes. Recurrent disturbances reduce the pool of mature adult colonies of reef-building corals and undermine post-disturbance recovery from newly settled recruits. Using a long-term interannual data set, we show that coral assemblages on the reef slope of Moorea, French Polynesia, have maintained a high capacity to recover despite a unique frequency of large-scale disturbances which, since the 1990s, have caused catastrophic declines in coral cover and abundance. In 2014, only four years after one of the most extreme cases of coral decline documented, abundance of juvenile and adult colonies had regained or exceeded pre-disturbance levels, and no phase-shift to macroalgal dominance was recorded. This rapid recovery has been achieved despite constantly low coral recruitment rates, suggesting a high post-disturbance survivorship of recruits. However, taxonomic differences in coral susceptibility to disturbances and contrasting recovery trajectories have resulted in changes in the relative composition of species. In the present context of global coral reef decline, our study establishes a new benchmark for the capacity of certain benthic reef communities to sustain and recover their coral cover from repeated, intense disturbances.
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Affiliation(s)
- Mehdi Adjeroud
- Institut de Recherche pour le Développement (IRD), UMR 9220 ENTROPIE, UPVD 52 avenue Paul Alduy, 66860, Perpignan, France.
- Laboratoire d'Excellence CORAIL, Perpignan, France.
| | - Mohsen Kayal
- USR 3278 CNRS-EPHE-UPVD, Centre de Recherches Insulaires et Observatoire de l'Environnement, UPVD 52 avenue Paul Alduy, 66860, Perpignan, France
| | - Claudie Iborra-Cantonnet
- Institut de Recherche pour le Développement (IRD), UMR 9220 ENTROPIE, UPVD 52 avenue Paul Alduy, 66860, Perpignan, France
| | - Julie Vercelloni
- Global Change Institute, The University of Queensland, Brisbane, QLD 4072, Queensland, Australia
- ARC Centre of Excellence for Coral Reef Studies, The University of Queensland, Brisbane, QLD 4072, Queensland, Australia
| | - Pauline Bosserelle
- Pacific Community (SPC), Fisheries, Aquaculture and Marine Ecosystem division, BP D5, 98848, Noumea, New Caledonia
| | - Vetea Liao
- USR 3278 CNRS-EPHE-UPVD, Centre de Recherches Insulaires et Observatoire de l'Environnement, UPVD 52 avenue Paul Alduy, 66860, Perpignan, France
| | - Yannick Chancerelle
- USR 3278 CNRS-EPHE-UPVD, Centre de Recherches Insulaires et Observatoire de l'Environnement, UPVD 52 avenue Paul Alduy, 66860, Perpignan, France
| | - Joachim Claudet
- Laboratoire d'Excellence CORAIL, Perpignan, France
- National Center for Scientific Research, PSL Université Paris, CRIOBE, USR 3278 CNRS-EPHE-UPVD, Maison des Océans, 195 rue Saint-Jacques, 75005, Paris, France
| | - Lucie Penin
- Laboratoire d'Excellence CORAIL, Perpignan, France
- Université de la Réunion, UMR 9220 ENTROPIE, 15 avenue René Cassin CS 92003, 97744, Saint Denis, Cédex 9, La Réunion, France
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36
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Carturan BS, Parrott L, Pither J. A modified trait‐based framework for assessing the resilience of ecosystem services provided by coral reef communities. Ecosphere 2018. [DOI: 10.1002/ecs2.2214] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Affiliation(s)
- Bruno S. Carturan
- Department of Biology University of British Columbia Okanagan Campus, 1177 Research Road Kelowna British Columbia V1V 1V7 Canada
- Institute for Biodiversity, Resilience, and Ecosystem Services University of British Columbia Okanagan Campus, 1177 Research Road Kelowna British Columbia V1V 1V7 Canada
| | - Lael Parrott
- Department of Biology University of British Columbia Okanagan Campus, 1177 Research Road Kelowna British Columbia V1V 1V7 Canada
- Institute for Biodiversity, Resilience, and Ecosystem Services University of British Columbia Okanagan Campus, 1177 Research Road Kelowna British Columbia V1V 1V7 Canada
- Department of Earth, Environmental and Geographic Sciences University of British Columbia Okanagan Campus, 1177 Research Road Kelowna British Columbia V1V 1V7 Canada
| | - Jason Pither
- Department of Biology University of British Columbia Okanagan Campus, 1177 Research Road Kelowna British Columbia V1V 1V7 Canada
- Institute for Biodiversity, Resilience, and Ecosystem Services University of British Columbia Okanagan Campus, 1177 Research Road Kelowna British Columbia V1V 1V7 Canada
- Department of Earth, Environmental and Geographic Sciences University of British Columbia Okanagan Campus, 1177 Research Road Kelowna British Columbia V1V 1V7 Canada
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37
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Conlan JA, Humphrey CA, Severati A, Francis DS. Influence of different feeding regimes on the survival, growth, and biochemical composition of Acropora coral recruits. PLoS One 2017; 12:e0188568. [PMID: 29182647 PMCID: PMC5705105 DOI: 10.1371/journal.pone.0188568] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 11/09/2017] [Indexed: 12/04/2022] Open
Abstract
Heterotrophic feeding in newly-settled coral planulae can potentially improve survivorship and accelerate early development in some species; however, an optimal diet to facilitate this does not currently exist. This study evaluated the efficacy of three heterotrophic feeding regimes (enriched rotifers, unfiltered seawater, and a novel, particulate diet), against a wholly-phototrophic treatment on Acropora hyacinthus, A. loripes, A. millepora, and A. tenuis recruits, over 93 days post-settlement. The unfiltered seawater treatment recorded maximum survival for all species (A. hyacinthus 95.9±8.0%, A. loripes: 74.3±11.5%, A. millepora: 67±12.7%, A. tenuis: 53.2±11.3%), although not significant. Growth (% surface area gain) was also greatest in the unfiltered seawater, and this was significant for A. millepora (870±307%) and A. tenuis (693±91.8%) (p<0.05). Although total lipid concentration was relatively stable across treatments, the lipid class composition exhibited species-specific responses to each treatment. Lower saturated and higher polyunsaturated fatty acids appeared beneficial to recruit performance, particularly in the unfiltered seawater, which generally contained the highest levels of 20:5n-3 (EPA), 22:6n-3 (DHA), and 20:4n-6 (ARA). The present study demonstrates the capacity of a nutritionally adequate and readily accepted heterotrophic feeding regime to increase coral recruit survival, growth, and health, which can greatly reduce the time required in cost- and labour-intensive culture.
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Affiliation(s)
- Jessica A. Conlan
- Deakin University, Geelong, Australia, School of Life and Environmental Sciences, Warrnambool Campus, Warrnambool, Victoria, Australia
- The National Sea Simulator, Australian Institute of Marine Science, Townsville, Queensland, Australia
- * E-mail:
| | - Craig A. Humphrey
- The National Sea Simulator, Australian Institute of Marine Science, Townsville, Queensland, Australia
| | - Andrea Severati
- The National Sea Simulator, Australian Institute of Marine Science, Townsville, Queensland, Australia
| | - David S. Francis
- Deakin University, Geelong, Australia, School of Life and Environmental Sciences, Warrnambool Campus, Warrnambool, Victoria, Australia
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A functional approach to the structural complexity of coral assemblages based on colony morphological features. Sci Rep 2017; 7:9849. [PMID: 28852107 PMCID: PMC5575326 DOI: 10.1038/s41598-017-10334-w] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 08/08/2017] [Indexed: 11/20/2022] Open
Abstract
Colony morphological features is among the best predictor of the scleractinian coral’s function in reef ecosystems. However, morphological traits are categorical and to convert this information into a quantitative value as well as estimate their influence on ecosystem process remain a challenge. Here, we propose a trait-based approach to quantify morphological diversity and assess the structural complexity of the habitat provided by corals. We used a previously published dataset that is related to a bleaching event that affected the coral reef off Tikus Island in Indonesia in 1983. We found clear signs of recovery of the coral assemblage’s complexity toward pre El Niño conditions five years after the event. Independent of the change observed in species richness, this return in structural complexity was accompanied by a global decrease in species number associated with each particular morphological entity (Functional Redundancy) and an increase in the number of single-species entities (Functional Vulnerability). Together with species loss, we show an overall functional erosion of the coral assemblage and suggest that the role of the coral reef habitat could be strongly imperiled under repeated or synergistic disturbances. This approach offers an opportunity for a better understanding of coral responses to natural and anthropogenic disturbances.
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Dubé CE, Boissin E, Maynard JA, Planes S. Fire coral clones demonstrate phenotypic plasticity among reef habitats. Mol Ecol 2017; 26:3860-3869. [DOI: 10.1111/mec.14165] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 03/02/2017] [Accepted: 04/24/2017] [Indexed: 11/29/2022]
Affiliation(s)
- Caroline E. Dubé
- PSL Research University; EPHE-UPVD-CNRS; USR 3278 CRIOBE; Université de Perpignan; Perpignan France
- Laboratoire d'Excellence “CORAIL”; Perpignan France
| | - Emilie Boissin
- PSL Research University; EPHE-UPVD-CNRS; USR 3278 CRIOBE; Université de Perpignan; Perpignan France
- Laboratoire d'Excellence “CORAIL”; Perpignan France
| | - Jeffrey A. Maynard
- Laboratoire d'Excellence “CORAIL”; Perpignan France
- SymbioSeas and Marine Applied Research Center; Wilmington NC USA
| | - Serge Planes
- PSL Research University; EPHE-UPVD-CNRS; USR 3278 CRIOBE; Université de Perpignan; Perpignan France
- Laboratoire d'Excellence “CORAIL”; Perpignan France
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Doropoulos C, Evensen NR, Gómez-Lemos LA, Babcock RC. Density-dependent coral recruitment displays divergent responses during distinct early life-history stages. ROYAL SOCIETY OPEN SCIENCE 2017; 4:170082. [PMID: 28573015 PMCID: PMC5451816 DOI: 10.1098/rsos.170082] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 04/20/2017] [Indexed: 05/30/2023]
Abstract
Population growth involves demographic bottlenecks that regulate recruitment success during various early life-history stages. The success of each early life-history stage can vary in response to population density, interacting with intrinsic (e.g. behavioural) and environmental (e.g. competition, predation) factors. Here, we used the common reef-building coral Acropora millepora to investigate how density-dependence influences larval survival and settlement in laboratory experiments that isolated intrinsic effects, and post-settlement survival in a field experiment that examined interactions with environmental factors. Larval survival was exceptionally high (greater than 80%) and density-independent from 2.5 to 12 days following spawning. By contrast, there was a weak positive effect of larval density on settlement, driven by gregarious behaviour at the highest density. When larval supply was saturated, settlement was three times higher in crevices compared with exposed microhabitats, but a negative relationship between settler density and post-settlement survival in crevices and density-independent survival on exposed surfaces resulted in similar recruit densities just one month following settlement. Moreover, a negative relationship was found between turf algae and settler survival in crevices, whereas gregarious settlement improved settler survival on exposed surfaces. Overall, our findings reveal divergent responses by coral larvae and newly settled recruits to density-dependent regulation, mediated by intrinsic and environmental interactions.
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Affiliation(s)
| | - Nicolas R. Evensen
- Marine Spatial Ecology Lab, Australia Research Council Centre of Excellence for Coral Reef Studies and School of Biological Sciences, The University of Queensland, St Lucia, Queensland 4072, Australia
| | - Luis A. Gómez-Lemos
- Griffith School of Environment, Australian Rivers Institute—Coast and Estuaries, Griffith University, Nathan, Queensland 4111, Australia
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Cumulative effects of suspended sediments, organic nutrients and temperature stress on early life history stages of the coral Acropora tenuis. Sci Rep 2017; 7:44101. [PMID: 28281658 PMCID: PMC5345069 DOI: 10.1038/srep44101] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Accepted: 02/01/2017] [Indexed: 11/08/2022] Open
Abstract
Coral reproduction is vulnerable to both declining water quality and warming temperatures, with simultaneous exposures likely compounding the negative impact of each stressor. We investigated how early life processes of the coral Acropora tenuis respond to increasing levels of suspended sediments in combination with temperature or organic nutrients. Fertilization success and embryo development were more sensitive to suspended sediments than to high temperatures or nutrient enrichment, while larval development (after acquisition of cilia) and settlement success were predominantly affected by thermal stress. Fertilization success was reduced 80% by suspended sediments, and up to 24% by temperature, while the addition of nutrients to suspended sediments had no further impact. Larval survivorship was unaffected by any of these treatments. However, settlement success of larvae developing from treatment-exposed embryos was negatively affected by all three stressors (e.g. up to 55% by suspended sediments), while exposure only during later larval stages predominantly responded to temperature stress. Environmentally relevant levels of suspended sediments and temperature had the greatest impacts, affecting more processes than the combined impacts of sediments and nutrients. These results suggest that management strategies to maintain suspended sediments at low concentrations during coral spawning events will benefit coral recruitment, especially with warming climate.
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Dubé CE, Mercière A, Vermeij MJA, Planes S. Population structure of the hydrocoral Millepora platyphylla in habitats experiencing different flow regimes in Moorea, French Polynesia. PLoS One 2017; 12:e0173513. [PMID: 28273119 PMCID: PMC5342305 DOI: 10.1371/journal.pone.0173513] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Accepted: 02/21/2017] [Indexed: 11/18/2022] Open
Abstract
While the fire coral Millepora platyphylla is an important component of Indo-Pacific reefs, where it thrives in a wide range of environments, the ecological and biological processes driving its distribution and population structure are not well understood. Here, we quantified this species’ population structure in five habitats with contrasting hydrodynamic regimes in Moorea, French Polynesia; two in the fore reef: mid and upper slopes, and three in the lagoon: back, fringing and patch reefs. A total of 3651 colonies of fire corals were mapped and measured over 45,000 m2 of surveyed reef. Due to the species’ sensitivity to fragmentation in response to strong water movement, hydrodynamic conditions (e.g. waves, pass and lagoonal circulation) corresponded to marked differences in colony size distributions, morphology and recruitment dynamics among habitats. The size structure varied among reef habitats with higher proportions of larger colonies in calm nearshore reefs (fringing and patch reefs), while populations were dominated by smaller colonies in the exposed fore reefs. The highest densities of fire corals were recorded in fore reef habitats (0.12–0.20 n.m-2) where the proportion of recruits and juveniles was higher at mid slope populations (49.3%) than on the upper slope near where waves break (29.0%). In the latter habitat, most colonies grew as vertical sheets on encrusting bases making them more vulnerable to colony fragmentation, whereas fire corals were encrusting or massive in all other habitats. The lowest densities of M. platyphylla occurred in lagoonal habitats (0.02–0.04 n.m-2) characterized by a combination of low water movement and other physical and biological stressors. This study reports the first evidence of population structure of fire corals in two common reef environments and illustrates the importance of water flow in driving population dynamic processes of these reef-building species.
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Affiliation(s)
- Caroline E. Dubé
- EPHE, PSL Research University, UPVD-CNRS, USR 3278 CRIOBE, Perpignan, France
- Laboratoire d’excellence “CORAIL”, EPHE, PSL Research University, UPVD-CNRS, USR 3278 CRIOBE, Papetoai, Moorea
- * E-mail:
| | - Alexandre Mercière
- Laboratoire d’excellence “CORAIL”, EPHE, PSL Research University, UPVD-CNRS, USR 3278 CRIOBE, Papetoai, Moorea
| | - Mark J. A. Vermeij
- CARMABI Foundation, Piscaderabaai z/n, Willemstad, Curaçao
- Aquatic Microbiology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Science Park 700, Amsterdam, The Netherlands
| | - Serge Planes
- EPHE, PSL Research University, UPVD-CNRS, USR 3278 CRIOBE, Perpignan, France
- Laboratoire d’excellence “CORAIL”, EPHE, PSL Research University, UPVD-CNRS, USR 3278 CRIOBE, Papetoai, Moorea
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The influence of resilience-based management on coral reef monitoring: A systematic review. PLoS One 2017; 12:e0172064. [PMID: 28187165 PMCID: PMC5302802 DOI: 10.1371/journal.pone.0172064] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 01/30/2017] [Indexed: 11/24/2022] Open
Abstract
With rapid changes taking place on coral reefs, managers and scientists are faced with prioritising interventions that might avoid undesirable losses in ecosystem health. The property of resilience captures how reefs react and respond to stressors and environmental changes. Therefore, in principle, management goals are more likely to be realised if resilience theory is used to inform decision making and help set realistic expectations for reef outcomes. Indeed, a new approach to reef management has been termed ‘resilience-based management’ (RBM). Yet, resilience concepts have often been criticised for being vague, difficult to operationalise, and beset by multiple definitions. Here, we evaluate how the advent of RBM has changed one aspect of reef management: assessment and monitoring. We compare the metrics used in conventional monitoring programs with those developed through resilience assessments and find that the latter have a stronger focus on ecological processes and exposure to environmental drivers. In contrast, monitoring tends to focus on metrics of reef state and has greater taxonomic resolution, which provides comprehensive information on the nature of changes but does not predict the future responses of reefs in part because it is difficult to extrapolate statistical trends of complex ecological systems. In addition, metrics measured by resilience studies are more diverse, owing in part to the reliance of state metrics as proxies of processes given the difficulty in quantifying key ecological processes directly. We conclude by describing practical ways of improving resilience assessments, and avenues for future research.
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Conlan JA, Humphrey CA, Severati A, Francis DS. Influence of different feeding regimes on the survival, growth, and biochemical composition of Acropora coral recruits. PLoS One 2017. [PMID: 29182647 DOI: 10.1371/journal.pone.0188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/15/2023] Open
Abstract
Heterotrophic feeding in newly-settled coral planulae can potentially improve survivorship and accelerate early development in some species; however, an optimal diet to facilitate this does not currently exist. This study evaluated the efficacy of three heterotrophic feeding regimes (enriched rotifers, unfiltered seawater, and a novel, particulate diet), against a wholly-phototrophic treatment on Acropora hyacinthus, A. loripes, A. millepora, and A. tenuis recruits, over 93 days post-settlement. The unfiltered seawater treatment recorded maximum survival for all species (A. hyacinthus 95.9±8.0%, A. loripes: 74.3±11.5%, A. millepora: 67±12.7%, A. tenuis: 53.2±11.3%), although not significant. Growth (% surface area gain) was also greatest in the unfiltered seawater, and this was significant for A. millepora (870±307%) and A. tenuis (693±91.8%) (p<0.05). Although total lipid concentration was relatively stable across treatments, the lipid class composition exhibited species-specific responses to each treatment. Lower saturated and higher polyunsaturated fatty acids appeared beneficial to recruit performance, particularly in the unfiltered seawater, which generally contained the highest levels of 20:5n-3 (EPA), 22:6n-3 (DHA), and 20:4n-6 (ARA). The present study demonstrates the capacity of a nutritionally adequate and readily accepted heterotrophic feeding regime to increase coral recruit survival, growth, and health, which can greatly reduce the time required in cost- and labour-intensive culture.
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Affiliation(s)
- Jessica A Conlan
- Deakin University, Geelong, Australia, School of Life and Environmental Sciences, Warrnambool Campus, Warrnambool, Victoria, Australia
- The National Sea Simulator, Australian Institute of Marine Science, Townsville, Queensland, Australia
| | - Craig A Humphrey
- The National Sea Simulator, Australian Institute of Marine Science, Townsville, Queensland, Australia
| | - Andrea Severati
- The National Sea Simulator, Australian Institute of Marine Science, Townsville, Queensland, Australia
| | - David S Francis
- Deakin University, Geelong, Australia, School of Life and Environmental Sciences, Warrnambool Campus, Warrnambool, Victoria, Australia
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Coral symbioses under prolonged environmental change: living near tolerance range limits. Sci Rep 2016; 6:36271. [PMID: 27805069 PMCID: PMC5090243 DOI: 10.1038/srep36271] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Accepted: 10/13/2016] [Indexed: 02/08/2023] Open
Abstract
As climate change progresses, understanding the long-term response of corals and their endosymbionts (Symbiodinium) to prolonged environmental change is of immediate importance. Here, a total of 1152 fragments from 72 colonies of three common coral species (Stylophora pistillata, Pocillopora damicornis, Seriatopora hystrix) underwent a 32-month reciprocal depth transplantation. Genetic analysis showed that while S. hystrix maintained its generalist symbiont, some S. pistillata and P. damicornis underwent temporary changes in resident symbionts immediately after stress (transplantation; natural bleaching). These temporary changes were phylogenetically constrained to ‘host-compatible’ symbionts only and reversion to original symbionts occurred within 7 to 12 months, indicating long-term fidelity and stability of adult symbioses. Measurements of symbiont photo-physiology (dark adapted yield, pressure over photosystem II) and coral health (host protein, bleaching status, mortality) indicated a broad acclimatory capacity. However, this came at an apparent energetic expense as disproportionate mortality amongst symbioses that persisted outside their distribution range was observed following a natural bleaching event. As environmental changes due to climate change become more continuous in nature, sub-lethal effects linked to the existence near tolerance range limits coupled with the inability of adult coral colonies to change resident symbionts makes corals particularly susceptible to additional environmental fluctuations or stress events and reduces the resilience of coral populations.
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Model suggests potential for Porites coral population recovery after removal of anthropogenic disturbance (Luhuitou, Hainan, South China Sea). Sci Rep 2016; 6:33324. [PMID: 27622504 PMCID: PMC5020734 DOI: 10.1038/srep33324] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Accepted: 08/16/2016] [Indexed: 11/09/2022] Open
Abstract
Population models are important for resource management and can inform about potential trajectories useful for planning purposes, even with incomplete monitoring data. From size frequency data on Luhuitou fringing reef, Hainan, South China Sea, a matrix population model of massive corals (Porites lutea) was developed and trajectories over 100 years under no disturbance and random disturbances were projected. The model reflects a largely open population of Porites lutea, with low local recruitment and preponderance of imported recruitment. Under no further disturbance, the population of Porites lutea will grow and its size structure will change from predominance of small size classes to large size classes. Therewith, total Porites cover will increase. Even under random disturbances every 10 to 20 years, the Porites population could remain viable, albeit at lower space cover. The models suggest recovery at Luhuitou following the removal of chronic anthropogenic disturbance. Extending the area of coral reef reserves to protect the open coral community and the path of connectivity is advisable and imperative for the conservation of Hainan's coral reefs.
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Luter HM, Duckworth AR, Wolff CW, Evans-Illidge E, Whalan S. Recruitment Variability of Coral Reef Sessile Communities of the Far North Great Barrier Reef. PLoS One 2016; 11:e0153184. [PMID: 27049650 PMCID: PMC4822782 DOI: 10.1371/journal.pone.0153184] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 03/24/2016] [Indexed: 11/19/2022] Open
Abstract
One of the key components in assessing marine sessile organism demography is determining recruitment patterns to benthic habitats. An analysis of serially deployed recruitment tiles across depth (6 and 12 m), seasons (summer and winter) and space (meters to kilometres) was used to quantify recruitment assemblage structure (abundance and percent cover) of corals, sponges, ascidians, algae and other sessile organisms from the northern sector of the Great Barrier Reef (GBR). Polychaetes were most abundant on recruitment titles, reaching almost 50% of total recruitment, yet covered <5% of each tile. In contrast, mean abundances of sponges, ascidians, algae, and bryozoans combined was generally less than 20% of total recruitment, with percentage cover ranging between 15–30% per tile. Coral recruitment was very low, with <1 recruit per tile identified. A hierarchal analysis of variation over a range of spatial and temporal scales showed significant spatio-temporal variation in recruitment patterns, but the highest variability occurred at the lowest spatial scale examined (1 m—among tiles). Temporal variability in recruitment of both numbers of taxa and percentage cover was also evident across both summer and winter. Recruitment across depth varied for some taxonomic groups like algae, sponges and ascidians, with greatest differences in summer. This study presents some of the first data on benthic recruitment within the northern GBR and provides a greater understanding of population ecology for coral reefs.
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Affiliation(s)
- Heidi M Luter
- NAMRA and the Australian Institute of Marine Science, Arafura Timor Research Facility, Darwin, NT, Australia
- Australian Institute of Marine Science, Townsville, QLD, Australia
| | - Alan R Duckworth
- Australian Institute of Marine Science, Townsville, QLD, Australia
| | - Carsten W Wolff
- Australian Institute of Marine Science, Townsville, QLD, Australia
| | | | - Steve Whalan
- Central Caribbean Marine Institute, Little Cayman, Cayman Islands
- Marine Ecology Research Centre, School of Environment, Science and Engineering, Southern Cross University, Lismore, NSW, Australia
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48
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Doropoulos C, Roff G, Bozec Y, Zupan M, Werminghausen J, Mumby PJ. Characterizing the ecological trade‐offs throughout the early ontogeny of coral recruitment. ECOL MONOGR 2016. [DOI: 10.1890/15-0668.1] [Citation(s) in RCA: 97] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Affiliation(s)
- Christopher Doropoulos
- Marine Spatial Ecology Lab Australian Research Council Centre of Excellence for Coral Reef Studies and School of Biological Sciences The University of Queensland Saint Lucia Queensland 4072 Australia
- Palau International Coral Reef Center Koror 96940 Palau
| | - George Roff
- Marine Spatial Ecology Lab Australian Research Council Centre of Excellence for Coral Reef Studies and School of Biological Sciences The University of Queensland Saint Lucia Queensland 4072 Australia
| | - Yves‐Marie Bozec
- Marine Spatial Ecology Lab Australian Research Council Centre of Excellence for Coral Reef Studies and School of Biological Sciences The University of Queensland Saint Lucia Queensland 4072 Australia
| | - Mirta Zupan
- Marine Spatial Ecology Lab Australian Research Council Centre of Excellence for Coral Reef Studies and School of Biological Sciences The University of Queensland Saint Lucia Queensland 4072 Australia
- Palau International Coral Reef Center Koror 96940 Palau
| | - Johanna Werminghausen
- Marine Spatial Ecology Lab Australian Research Council Centre of Excellence for Coral Reef Studies and School of Biological Sciences The University of Queensland Saint Lucia Queensland 4072 Australia
| | - Peter J. Mumby
- Marine Spatial Ecology Lab Australian Research Council Centre of Excellence for Coral Reef Studies and School of Biological Sciences The University of Queensland Saint Lucia Queensland 4072 Australia
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Gibbs DA, Hay ME. Spatial patterns of coral survivorship: impacts of adult proximity versus other drivers of localized mortality. PeerJ 2015; 3:e1440. [PMID: 26623193 PMCID: PMC4662597 DOI: 10.7717/peerj.1440] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2015] [Accepted: 11/04/2015] [Indexed: 11/20/2022] Open
Abstract
Species-specific enemies may promote prey coexistence through negative distance- and density-dependent survival of juveniles near conspecific adults. We tested this mechanism by transplanting juvenile-sized fragments of the brooding corals Pocillopora damicornis and Seriatopora hystrix 3, 12, 24 and 182 cm up- and down-current of conspecific adults and monitoring their survival and condition over time. We also characterized the spatial distribution of P. damicornis and S. hystrix within replicate plots on three Fijian reef flats and measured the distribution of small colonies within 2 m of larger colonies of each species. Juvenile-sized transplants exhibited no differences in survivorship as a function of distance from adult P. damicornis or S. hystrix. Additionally, both P. damicornis and S. hystrix were aggregated rather than overdispersed on natural reefs. However, a pattern of juveniles being aggregated near adults while larger (and probably older) colonies were not suggests that greater mortality near large adults could occur over longer periods of time or that size-dependent mortality was occurring. While we found minimal evidence of greater mortality of small colonies near adult conspecifics in our transplant experiments, we did document hot-spots of species-specific corallivory. We detected spatially localized and temporally persistent predation on P. damicornis by the territorial triggerfish Balistapus undulatus. This patchy predation did not occur for S. hystrix. This variable selective regime in an otherwise more uniform environment could be one mechanism maintaining diversity of corals on Indo-Pacific reefs.
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Affiliation(s)
- David A Gibbs
- School of Biology, Georgia Institute of Technology , Atlanta, GA , United States ; Current affiliation: Tetra Tech, Inc. , Atlanta, GA , United States
| | - Mark E Hay
- School of Biology and Aquatic Chemical Ecology Center, Georgia Institute of Technology , Atlanta, GA , United States
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50
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Mumby PJ, Steneck RS, Adjeroud M, Arnold SN. High resilience masks underlying sensitivity to algal phase shifts of Pacific coral reefs. OIKOS 2015. [DOI: 10.1111/oik.02673] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Peter J. Mumby
- Marine Spatial Ecology Lab, ARC Centre of Excellence for Coral Reef Studies, School of Biological Sciences, The Univ. of Queensland; St Lucia Qld 4072 Australia
| | - Robert S. Steneck
- Darling Marine Center, Univ. of Maine; 193 Clarks Cove Road Walpole ME 04573 USA
| | - Mehdi Adjeroud
- Inst. de Recherche pour le Développement, UMR 9220 ENTROPIE /Laboratoire d'Excellence “CORAIL”; 5 Université de Perpignan, 52 avenue Paul Alduy FR-66860 Perpignan France
| | - Suzanne N. Arnold
- Darling Marine Center, Univ. of Maine; 193 Clarks Cove Road Walpole ME 04573 USA
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