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McLaren E, Sommer B, Pandolfi JM, Beger M, Byrne M. Taxa-dependent temporal trends in the abundance and size of sea urchins in subtropical eastern Australia. Ecol Evol 2024; 14:e11412. [PMID: 38770118 PMCID: PMC11103280 DOI: 10.1002/ece3.11412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2024] [Revised: 04/30/2024] [Accepted: 05/02/2024] [Indexed: 05/22/2024] Open
Abstract
Subtropical reefs host a dynamic mix of tropical, subtropical, and temperate species that is changing due to shifts in the abundance and distribution of species in response to ocean warming. In these transitional communities, biogeographic affinity is expected to predict changes in species composition, with projected increases of tropical species and declines in cool-affinity temperate species. Understanding population dynamics of species along biogeographic transition zones is critical, especially for habitat engineers such as sea urchins that can facilitate ecosystem shifts through grazing. We investigated the population dynamics of sea urchins on coral-associated subtropical reefs at 7 sites in eastern Australia (28.196° S to 30.95° S) over 9 years (2010-2019), a period impacted by warming and heatwaves. Specifically, we investigated the density and population size structure of taxa with temperate (Centrostephanus rodgersii, Phyllacanthus parvispinus), subtropical (Tripneustes australiae) and tropical (Diadema spp.) affinities. Counter to expectation, biogeographic affinity did not explain shifts in species abundances in this region. Although we expected the abundance of tropical species to increase at their cold range boundaries, tropical Diadema species declined across all sites. The subtropical T. australiae also showed declines, while populations of the temperate C. rodgersii were remarkably stable throughout our study period. Our results show that temporal patterns of sea urchin populations in this region cannot be predicted by bio-geographic affinity alone and contribute critical information about the population dynamics of these important herbivores along this biogeographic transition zone.
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Affiliation(s)
- Emily McLaren
- School of Life and Environmental Sciences, Coastal and Marine Ecosystems GroupThe University of SydneySydneyNew South WalesAustralia
| | - Brigitte Sommer
- School of Life and Environmental Sciences, Coastal and Marine Ecosystems GroupThe University of SydneySydneyNew South WalesAustralia
| | - John M. Pandolfi
- School of the EnvironmentThe University of QueenslandSt. LuciaQueenslandAustralia
| | - Maria Beger
- School of Biology, Faculty of Biological SciencesUniversity of LeedsLeedsUK
- Centre for Biodiversity and Conservation Science, School of the EnvironmentThe University of QueenslandSt. LuciaQueenslandAustralia
| | - Maria Byrne
- School of Life and Environmental Sciences, Coastal and Marine Ecosystems GroupThe University of SydneySydneyNew South WalesAustralia
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2
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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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3
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Choi S, Yang JW, Kim JE, Jeon H, Shin S, Wui D, Kim LS, Kim BJ, Son H, Min K. Infectivity and stress tolerance traits affect community assembly of plant pathogenic fungi. Front Microbiol 2023; 14:1234724. [PMID: 37692392 PMCID: PMC10486888 DOI: 10.3389/fmicb.2023.1234724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Accepted: 07/26/2023] [Indexed: 09/12/2023] Open
Abstract
Understanding how ecological communities assemble is an urgent research priority. In this study, we used a community ecology approach to examine how ecological and evolutionary processes shape biodiversity patterns of plant pathogenic fungi, Fusarium graminearum and F. asiaticum. High-throughput screening revealed that the isolates had a wide range of phenotypic variation in stress tolerance traits. Net Relatedness Index (NRI) and Nearest Taxon Index (NTI) values were computed based on stress-tolerant distance matrices. Certain local regions exhibited positive values of NRI and NTI, indicating phenotypic clustering within the fungal communities. Competition assays of the pooled strains were conducted to investigate the cause of clustering. During stress conditions and wheat colonization, only a few strains dominated the fungal communities, resulting in reduced diversity. Overall, our findings support the modern coexistence theory that abiotic stress and competition lead to phenotypic similarities among coexisting organisms by excluding large, low-competitive clades. We suggest that agricultural environments and competition for host infection lead to locally clustered communities of plant pathogenic fungi in the field.
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Affiliation(s)
- Soyoung Choi
- Department of Agricultural Biotechnology, Seoul National University, Seoul, Republic of Korea
| | - Jung Wook Yang
- Crop Cultivation and Environment Research Division, National Institute of Crop Science, Rural Development Administration, Suwon, Republic of Korea
| | - Jung-Eun Kim
- Research Institute of Climate Change and Agriculture, National Institute of Horticultural and Herbal Science, Rural Development Administration, Jeju, Republic of Korea
| | - Hosung Jeon
- Department of Agricultural Biotechnology, Seoul National University, Seoul, Republic of Korea
| | - Soobin Shin
- Department of Agricultural Biotechnology, Seoul National University, Seoul, Republic of Korea
| | - Dayoun Wui
- Department of Agricultural Biotechnology, Seoul National University, Seoul, Republic of Korea
| | - Lee Seul Kim
- Department of Agricultural Biotechnology, Seoul National University, Seoul, Republic of Korea
| | - Byung Joo Kim
- Crop Cultivation and Environment Research Division, National Institute of Crop Science, Rural Development Administration, Suwon, Republic of Korea
| | - Hokyoung Son
- Department of Agricultural Biotechnology, Seoul National University, Seoul, Republic of Korea
- Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, Republic of Korea
| | - Kyunghun Min
- Department of Agricultural Biotechnology, Seoul National University, Seoul, Republic of Korea
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4
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Schoepf V, Baumann JH, Barshis DJ, Browne NK, Camp EF, Comeau S, Cornwall CE, Guzmán HM, Riegl B, Rodolfo-Metalpa R, Sommer B. Corals at the edge of environmental limits: A new conceptual framework to re-define marginal and extreme coral communities. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 884:163688. [PMID: 37105476 DOI: 10.1016/j.scitotenv.2023.163688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 04/14/2023] [Accepted: 04/19/2023] [Indexed: 05/07/2023]
Abstract
The worldwide decline of coral reefs has renewed interest in coral communities at the edge of environmental limits because they have the potential to serve as resilience hotspots and climate change refugia, and can provide insights into how coral reefs might function in future ocean conditions. These coral communities are often referred to as marginal or extreme but few definitions exist and usage of these terms has therefore been inconsistent. This creates significant challenges for categorising these often poorly studied communities and synthesising data across locations. Furthermore, this impedes our understanding of how coral communities can persist at the edge of their environmental limits and the lessons they provide for future coral reef survival. Here, we propose that marginal and extreme coral communities are related but distinct and provide a novel conceptual framework to redefine them. Specifically, we define coral reef extremeness solely based on environmental conditions (i.e., large deviations from optimal conditions in terms of mean and/or variance) and marginality solely based on ecological criteria (i.e., altered community composition and/or ecosystem functioning). This joint but independent assessment of environmental and ecological criteria is critical to avoid common pitfalls where coral communities existing outside the presumed optimal conditions for coral reef development are automatically considered inferior to coral reefs in more traditional settings. We further evaluate the differential potential of marginal and extreme coral communities to serve as natural laboratories, resilience hotspots and climate change refugia, and discuss strategies for their conservation and management as well as priorities for future research. Our new classification framework provides an important tool to improve our understanding of how corals can persist at the edge of their environmental limits and how we can leverage this knowledge to optimise strategies for coral reef conservation, restoration and management in a rapidly changing ocean.
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Affiliation(s)
- Verena Schoepf
- Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, the Netherlands; UWA Oceans Institute, University of Western Australia, Perth, Western Australia, Australia.
| | - Justin H Baumann
- Department of Biology, Mount Holyoke College, South Hadley, MA, USA
| | - Daniel J Barshis
- Department of Biological Sciences, Old Dominion University, Norfolk, VA, USA
| | - Nicola K Browne
- School of Molecular and Life Sciences, Curtin University, Perth, Western Australia, Australia
| | - Emma F Camp
- Climate Change Cluster, University of Technology Sydney, Sydney, New South Wales, Australia
| | - Steeve Comeau
- Sorbonne Université, CNRS-INSU, Laboratoire d'Océanographie de Villefranche, Villefranche-sur-mer, France
| | - Christopher E Cornwall
- School of Biological Sciences and Coastal People: Southern Skies, Victoria University of Wellington, Wellington, New Zealand
| | - Héctor M Guzmán
- Smithsonian Tropical Research Institute, Panama, Republic of Panama
| | - Bernhard Riegl
- Department of Marine and Environmental Sciences, Halmos College of Arts and Sciences, Nova Southeastern University, Dania Beach, FL, USA
| | - Riccardo Rodolfo-Metalpa
- ENTROPIE, IRD, Université de la Réunion, CNRS, IFREMER, Université de Nouvelle-Calédonie, Nouméa, New Caledonia; Labex ICONA, International CO(2) Natural Analogues Network, Japan
| | - Brigitte Sommer
- School of Life Sciences, University of Technology Sydney, Sydney, New South Wales, Australia; School of Life and Environmental Sciences, The University of Sydney, Sydney, New South Wales, Australia
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5
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Paúl MJ, Rosauer D, Tarroso P, Velo‐Antón G, Carvalho SB. Environmental and topographic drivers of amphibian phylogenetic diversity and endemism in the Iberian Peninsula. Ecol Evol 2023; 13:e9666. [PMID: 36620407 PMCID: PMC9817204 DOI: 10.1002/ece3.9666] [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: 06/02/2022] [Revised: 11/30/2022] [Accepted: 12/07/2022] [Indexed: 01/09/2023] Open
Abstract
Understanding the ecological and evolutionary processes driving biodiversity patterns and allowing their persistence is of utmost importance. Many hypotheses have been proposed to explain spatial diversity patterns, including water-energy availability, habitat heterogeneity, and historical climatic refugia. The main goal of this study is to identify if general spatial drivers of species diversity patterns of phylogenetic diversity (PD) and phylogenetic endemism (PE) at the global scale are also predictive of PD and PE at regional scales, using Iberian amphibians as a case study. Our main hypothesis assumes that topography along with contemporary and historical climate are drivers of phylogenetic diversity and endemism, but that the strength of these predictors may be weaker at the regional scale than it tends to be at the global scale. We mapped spatial patterns of Iberian amphibians' phylogenetic diversity and endemism, using previously published phylogenetic and distribution data. Furthermore, we compiled spatial data on topographic and climatic variables related to the water-energy availability, topography, and historical climatic instability hypotheses. To test our hypotheses, we used Spatial Autoregressive Models and selected the best model to explain diversity patterns based on Akaike Information Criterion. Our results show that, out of the variables tested in our study, water-energy availability and historical climate instability are the most important drivers of amphibian diversity in Iberia. However, as predicted, the strength of these predictors in our case study is weaker than it tends to be at global scales. Thus, additional drivers should also be investigated and we suggest caution when interpreting these predictors as surrogates for different components of diversity.
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Affiliation(s)
- Maria João Paúl
- CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO Laboratório Associado, Campus de VairãoUniversidade do PortoVairãoPortugal,BIOPOLIS Program in Genomics, Biodiversity and Land PlanningCIBIOVairãoPortugal,Departamento de Biologia, Faculdade de CiênciasUniversidade do PortoPortoPortugal
| | - Dan Rosauer
- Division of Ecology and Evolution, Research School of Biology and Centre for Biodiversity AnalysisThe Australian National UniversityCanberraAustralian Capital TerritoryAustralia
| | - Pedro Tarroso
- CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO Laboratório Associado, Campus de VairãoUniversidade do PortoVairãoPortugal,BIOPOLIS Program in Genomics, Biodiversity and Land PlanningCIBIOVairãoPortugal
| | - Guillermo Velo‐Antón
- CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO Laboratório Associado, Campus de VairãoUniversidade do PortoVairãoPortugal,BIOPOLIS Program in Genomics, Biodiversity and Land PlanningCIBIOVairãoPortugal,Departamento de Ecoloxía e Bioloxía Animal, Grupo de Ecoloxía Animal, Torre Cacti (Lab 97)Universidade de VigoVigoSpain
| | - Sílvia B. Carvalho
- CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO Laboratório Associado, Campus de VairãoUniversidade do PortoVairãoPortugal,BIOPOLIS Program in Genomics, Biodiversity and Land PlanningCIBIOVairãoPortugal
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6
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Factors Limiting the Range Extension of Corals into High-Latitude Reef Regions. DIVERSITY 2021. [DOI: 10.3390/d13120632] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Reef-building corals show a marked decrease in total species richness from the tropics to high latitude regions. Several hypotheses have been proposed to account for this pattern in the context of abiotic and biotic factors, including temperature thresholds, light limitation, aragonite saturation, nutrient or sediment loads, larval dispersal constraints, competition with macro-algae or other invertebrates, and availability of suitable settlement cues or micro-algal symbionts. Surprisingly, there is a paucity of data supporting several of these hypotheses. Given the immense pressures faced by corals in the Anthropocene, it is critical to understand the factors limiting their distribution in order to predict potential range expansions and the role that high latitude reefs can play as refuges from climate change. This review examines these factors and outlines critical research areas to address knowledge gaps in our understanding of light/temperature interactions, coral-Symbiodiniaceae associations, settlement cues, and competition in high latitude reefs.
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7
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Gheyret G, Guo Y, Fang J, Tang Z. Latitudinal and elevational patterns of phylogenetic structure in forest communities in China's mountains. SCIENCE CHINA. LIFE SCIENCES 2020; 63:1895-1904. [PMID: 32382981 DOI: 10.1007/s11427-019-1663-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Accepted: 03/23/2020] [Indexed: 11/29/2022]
Abstract
The phylogenetic structure incorporates both ecological and evolutionary processes to explain assembly of a local community. The "phylogenetic niche conservatism" (PNC) hypothesis suggests that distributions of species along environmental gradients reflect both ancestral traits and ecological fitness of individual species The temperature is generally regarded to change in similar ways along both latitudinal and elevational gradients but with different historical contingence. Therefore, comparing the latitudinal and elevational patterns of phylogenetic structure of communities is of help to depict the effects of ecological and evolutionary processes in shaping the community assembly. In this study, we explored the latitudinal, elevational and climatic patterns of phylogenetic structure of 569 angiosperm tree communities from 38 mountains across China. We found a larger mean abundance-weighted net relatedness index (NRI) than the presence/absence-based NRI; and the NRI decreased when the species pool downscaled from the full pool to county-level pool. The mean family age and phylogenetic species evenness decreased with latitude, and increased with temperature of the coldest month and precipitation; whilst NRI increased with latitude, and decreased with mean temperature of the coldest month. In most mountains, NRI, mean family age and phylogenetic species evenness showed non-significant trends along the elevational gradient. Our results support the main predictions of PNC for the latitudinal gradient, i.e., species tend to be more phylogenetically related to each other and clades are younger in temperate environments, compared to those in tropical environments. We suggested that independent species pools and abundance should be incorporated in analysis to fully represent the phylogenetic structure of communities.
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Affiliation(s)
- Gheyur Gheyret
- Institute of Ecology, College of Urban and Environmental Sciences and Key Laboratory for Earth Surface Processes of Ministry of Education, Peking University, Beijing, 100871, China
| | - Yanpei Guo
- Institute of Ecology, College of Urban and Environmental Sciences and Key Laboratory for Earth Surface Processes of Ministry of Education, Peking University, Beijing, 100871, China
| | - Jingyun Fang
- Institute of Ecology, College of Urban and Environmental Sciences and Key Laboratory for Earth Surface Processes of Ministry of Education, Peking University, Beijing, 100871, China
| | - Zhiyao Tang
- Institute of Ecology, College of Urban and Environmental Sciences and Key Laboratory for Earth Surface Processes of Ministry of Education, Peking University, Beijing, 100871, China.
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8
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Cant J, Salguero-Gómez R, Kim SW, Sims CA, Sommer B, Brooks M, Malcolm HA, Pandolfi JM, Beger M. The projected degradation of subtropical coral assemblages by recurrent thermal stress. J Anim Ecol 2020; 90:233-247. [PMID: 32920820 DOI: 10.1111/1365-2656.13340] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Accepted: 08/31/2020] [Indexed: 11/28/2022]
Abstract
Subtropical coral assemblages are threatened by similar extreme thermal stress events to their tropical counterparts. Yet, the mid- and long-term thermal stress responses of corals in subtropical environments remain largely unquantified, limiting our capacity to predict their future viability. The annual survival, growth and recruitment of 311 individual corals within the Solitary Islands Marine Park (Australia) was recorded over a 3-year period (2016-2018), including the 2015/2016 thermal stress event. These data were used to parameterise integral projection models quantifying the effect of thermal stress within a subtropical coral assemblage. Stochastic simulations were also applied to evaluate the implications of recurrent thermal stress scenarios predicted by four different Representative Concentration Pathways. We report differential shifts in population growth rates (λ) among coral populations during both stress and non-stress periods, confirming contrasting bleaching responses among taxa. However, even during non-stress periods, the observed dynamics for all taxa were unable to maintain current community composition, highlighting the need for external recruitment sources to support the community structure. Across all coral taxa, projected stochastic growth rates (λs ) were found to be lowest under higher emissions scenarios. Correspondingly, predicted increases in recurrent thermal stress regimes may accelerate the loss of coral coverage, species diversity and structural complexity within subtropical regions. We suggest that these trends are primarily due to the susceptibility of subtropical specialists and endemic species, such as Pocillopora aliciae, to thermal stress. Similarly, the viability of many tropical coral populations at higher latitudes is highly dependent on the persistence of up-current tropical systems. As such, the inherent dynamics of subtropical coral populations appear unable to support their future persistence under unprecedented thermal disturbance scenarios.
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Affiliation(s)
- James Cant
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK
| | - Roberto Salguero-Gómez
- Department of Zoology, University of Oxford, Oxford, UK.,Centre for Biodiversity and Conservation Science, School of Biological Sciences, University of Queensland, Brisbane, QLD, Australia.,Max Planck Institute for Demographic Research, Rostock, Germany
| | - Sun W Kim
- Australian Research Council Centre of Excellence for Coral Reef Studies, School of Biological Sciences, The University of Queensland, Brisbane, QLD, Australia
| | - Carrie A Sims
- Australian Research Council Centre of Excellence for Coral Reef Studies, School of Biological Sciences, The University of Queensland, Brisbane, QLD, Australia
| | - Brigitte Sommer
- School of Life and Environmental Science, University of Sydney, Camperdown, NSW, Australia
| | - Maxime Brooks
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK
| | - Hamish A Malcolm
- Fisheries Research, NSW Department of Primary Industries, Coffs Harbour, NSW, Australia
| | - John M Pandolfi
- Australian Research Council Centre of Excellence for Coral Reef Studies, School of Biological Sciences, The University of Queensland, Brisbane, QLD, Australia
| | - Maria Beger
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK.,Centre for Biodiversity and Conservation Science, School of Biological Sciences, University of Queensland, Brisbane, QLD, Australia
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9
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Kim SW, Sampayo EM, Sommer B, Sims CA, Gómez-Cabrera MDC, Dalton SJ, Beger M, Malcolm HA, Ferrari R, Fraser N, Figueira WF, Smith SDA, Heron SF, Baird AH, Byrne M, Eakin CM, Edgar R, Hughes TP, Kyriacou N, Liu G, Matis PA, Skirving WJ, Pandolfi JM. Refugia under threat: Mass bleaching of coral assemblages in high-latitude eastern Australia. GLOBAL CHANGE BIOLOGY 2019; 25:3918-3931. [PMID: 31472029 DOI: 10.1111/gcb.14772] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 05/31/2019] [Accepted: 07/04/2019] [Indexed: 05/21/2023]
Abstract
Environmental anomalies that trigger adverse physiological responses and mortality are occurring with increasing frequency due to climate change. At species' range peripheries, environmental anomalies are particularly concerning because species often exist at their environmental tolerance limits and may not be able to migrate to escape unfavourable conditions. Here, we investigated the bleaching response and mortality of 14 coral genera across high-latitude eastern Australia during a global heat stress event in 2016. We evaluated whether the severity of assemblage-scale and genus-level bleaching responses was associated with cumulative heat stress and/or local environmental history, including long-term mean temperatures during the hottest month of each year (SSTLTMAX ), and annual fluctuations in water temperature (SSTVAR ) and solar irradiance (PARZVAR ). The most severely-bleached genera included species that were either endemic to the region (Pocillopora aliciae) or rare in the tropics (e.g. Porites heronensis). Pocillopora spp., in particular, showed high rates of immediate mortality. Bleaching severity of Pocillopora was high where SSTLTMAX was low or PARZVAR was high, whereas bleaching severity of Porites was directly associated with cumulative heat stress. While many tropical Acropora species are extremely vulnerable to bleaching, the Acropora species common at high latitudes, such as A. glauca and A. solitaryensis, showed little incidence of bleaching and immediate mortality. Two other regionally-abundant genera, Goniastrea and Turbinaria, were also largely unaffected by the thermal anomaly. The severity of assemblage-scale bleaching responses was poorly explained by the environmental parameters we examined. Instead, the severity of assemblage-scale bleaching was associated with local differences in species abundance and taxon-specific bleaching responses. The marked taxonomic disparity in bleaching severity, coupled with high mortality of high-latitude endemics, point to climate-driven simplification of assemblage structures and progressive homogenisation of reef functions at these high-latitude locations.
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Affiliation(s)
- Sun W Kim
- Australian Research Council Centre of Excellence for Coral Reef Studies, School of Biological Sciences, The University of Queensland, St. Lucia, QLD, Australia
| | - Eugenia M Sampayo
- Australian Research Council Centre of Excellence for Coral Reef Studies, School of Biological Sciences, The University of Queensland, St. Lucia, QLD, Australia
| | - Brigitte Sommer
- Australian Research Council Centre of Excellence for Coral Reef Studies, School of Biological Sciences, The University of Queensland, St. Lucia, QLD, Australia
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, Australia
| | - Carrie A Sims
- Australian Research Council Centre of Excellence for Coral Reef Studies, School of Biological Sciences, The University of Queensland, St. Lucia, QLD, Australia
| | - Maria Del C Gómez-Cabrera
- Australian Research Council Centre of Excellence for Coral Reef Studies, School of Biological Sciences, The University of Queensland, St. Lucia, QLD, Australia
| | - Steve J Dalton
- Australian Research Council Centre of Excellence for Coral Reef Studies, School of Biological Sciences, The University of Queensland, St. Lucia, QLD, Australia
| | - Maria Beger
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK
- School of Biological Sciences, Centre for Biodiversity and Conservation Science, The University of Queensland, St. Lucia, QLD, Australia
| | - Hamish A Malcolm
- Fisheries Research, New South Wales Department of Primary Industries, Coffs Harbour, NSW, Australia
| | - Renata Ferrari
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, Australia
- Australian Institute of Marine Sciences, Townsville, QLD, Australia
| | - Nicola Fraser
- Solitary Islands Underwater Research Group, Coffs Harbour, NSW, Australia
| | - Will F Figueira
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, Australia
| | - Stephen D A Smith
- National Marine Science Centre, Southern Cross University, Coffs Harbour, NSW, Australia
| | - Scott F Heron
- Marine Geophysical Laboratory, Physics Department, College of Science and Engineering, James Cook University, Townsville, QLD, Australia
- Coral Reef Watch, U.S. National Oceanic and Atmospheric Administration, College Park, MD, USA
| | - Andrew H Baird
- Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD, Australia
| | - Maria Byrne
- Anatomy and Histology, Bosch Institute, The University of Sydney, Sydney, NSW, Australia
| | - C Mark Eakin
- Coral Reef Watch, U.S. National Oceanic and Atmospheric Administration, College Park, MD, USA
| | - Robert Edgar
- Solitary Islands Underwater Research Group, Coffs Harbour, NSW, Australia
| | - Terry P Hughes
- Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD, Australia
| | - Nicole Kyriacou
- Australian Research Council Centre of Excellence for Coral Reef Studies, School of Biological Sciences, The University of Queensland, St. Lucia, QLD, Australia
| | - Gang Liu
- Coral Reef Watch, U.S. National Oceanic and Atmospheric Administration, College Park, MD, USA
- Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD, USA
| | - Paloma A Matis
- School of Life Sciences, University of Technology Sydney, Broadway, NSW, Australia
| | - William J Skirving
- Coral Reef Watch, U.S. National Oceanic and Atmospheric Administration, College Park, MD, USA
| | - John M Pandolfi
- Australian Research Council Centre of Excellence for Coral Reef Studies, School of Biological Sciences, The University of Queensland, St. Lucia, QLD, Australia
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10
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Muir PR, Wallace CC, Pichon M, Bongaerts P. High species richness and lineage diversity of reef corals in the mesophotic zone. Proc Biol Sci 2018; 285:20181987. [PMID: 30963905 PMCID: PMC6304044 DOI: 10.1098/rspb.2018.1987] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Accepted: 11/17/2018] [Indexed: 11/12/2022] Open
Abstract
Coral reefs are increasingly threatened by thermal bleaching and tropical storm events associated with rising sea surface temperatures. Deeper habitats offer some protection from these impacts and may safeguard reef-coral biodiversity, but their faunas are largely undescribed for the Indo-Pacific. Here, we show high species richness of scleractinian corals in mesophotic habitats (30-125 m) for the northern Great Barrier Reef region that greatly exceeds previous records for mesophotic habitats globally. Overall, 45% of shallow-reef species (less than or equal to 30 m), 78% of genera, and all families extended below 30 m depth, with 13% of species, 41% of genera, and 78% of families extending below 45 m. Maximum depth of occurrence showed a weak relationship to phylogeny, but a strong correlation with maximum latitudinal extent. Species recorded in the mesophotic had a significantly greater than expected probability of also occurring in shaded microhabitats and at higher latitudes, consistent with light as a common limiting factor. The findings suggest an important role for deeper habitats, particularly depths 30-45 m, in preserving evolutionary lineages of Indo-Pacific corals. Deeper reef areas are clearly more diverse than previously acknowledged and therefore deserve full consideration in our efforts to protect the world's coral reef biodiversity.
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Affiliation(s)
- Paul R. Muir
- Queensland Museum, Biodiversity and Geosciences, Townsville, Queensland 4810, Australia
| | - Carden C. Wallace
- Queensland Museum, Biodiversity and Geosciences, South Brisbane, Queensland 4101, Australia
| | - Michel Pichon
- Queensland Museum, Biodiversity and Geosciences, Townsville, Queensland 4810, Australia
| | - Pim Bongaerts
- Global Change Institute, The University of Queensland, St Lucia, Queensland 4072, Australia
- California Academy of Sciences, San Francisco, CA 94118, USA
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