1
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Mellin C, Stuart-Smith RD, Heather F, Oh E, Turak E, Edgar GJ. Coral responses to a catastrophic marine heatwave are decoupled from changes in total coral cover at a continental scale. Proc Biol Sci 2024; 291:20241538. [PMID: 39378994 PMCID: PMC11461067 DOI: 10.1098/rspb.2024.1538] [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: 10/04/2023] [Revised: 08/20/2024] [Accepted: 08/27/2024] [Indexed: 10/10/2024] Open
Abstract
The services provided by the world's coral reefs are threatened by increasingly frequent and severe marine heatwaves. Heatwave-induced degradation of reefs has often been inferred from the extent of the decline in total coral cover, which overlooks extreme variation among coral taxa in their susceptibility and responses to thermal stress. Here, we provide a continental-scale assessment of coral cover changes at 262 shallow tropical reef sites around Australia, using ecological survey data on 404 coral taxa before and after the 2016 mass bleaching event. A strong spatial structure in coral community composition along large-scale environmental gradients largely dictated how coral communities responded to heat stress. While heat stress variables were the best predictors of change in total coral cover, the pre-heatwave community composition best predicted the temporal beta-diversity index (an indicator of change in community composition over time). Indicator taxa in each coral community differed before and after the heatwave, highlighting potential winners and losers of climate-driven coral bleaching. Our results demonstrate how assessment of change in total cover alone may conceal very different responses in community structure, some of which showed strong regional consistency, and may provide a telling outlook of how coral reefs may reorganize in a warmer future.
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Affiliation(s)
- Camille Mellin
- The Environment Institute and School of Biological Sciences, University of Adelaide, Adelaide, South Australia5005, Australia
| | - Rick D. Stuart-Smith
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia
| | - Freddie Heather
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia
| | - Elizabeth Oh
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia
| | - Emre Turak
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia
| | - Graham J. Edgar
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia
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2
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Zhong R, Liu S, Chen S, Zhao L, Yang D. Satellite observations reveal anthropogenic pressure significantly affects the suspended particulate matter concentrations in coastal waters of Hainan Island. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 365:121617. [PMID: 38968896 DOI: 10.1016/j.jenvman.2024.121617] [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: 04/08/2024] [Revised: 06/13/2024] [Accepted: 06/24/2024] [Indexed: 07/07/2024]
Abstract
Suspended particulate matter (SPM) plays a crucial role in assessing the health status of coastal ecosystems. Satellite remote sensing offers an effective approach to investigate the variations and distribution patterns of SPM, with the performance of various satellite retrieval models exhibiting significant spatial heterogeneity. However, there is still limited information on precise remote sensing retrieval algorithms specifically designed for estimating SPM in tropical areas, hindering our ability to monitor the health status of valuable tropical ecological resources. A relatively accurate empirical algorithm (root mean square error = 2.241 mg L-1, mean absolute percentage error = 42.527%) was first developed for the coastal SPM of Hainan Island based on MODIS images and over a decade of field SPM data, which conducted comprehensive comparisons among empirical models, semi-analytical models, and machine learning models. Long-term monitoring from 2003 to 2022 revealed that the average SPM concentration along the coastal wetlands of Hainan Island was 6.848 mg L-1, which displayed a decreasing trend due to government environmental protection regulations (average rate of change of -0.009 mg L-1/year). The seasonal variations in coastal SPM were primarily influenced by sea surface temperature (SST). Spatially, the concentrations of SPM along the southwest coast of Hainan Island were higher in comparison to other waters, which was attributable to sediment types and ocean currents. Further, anthropogenic pressure (e.g., agricultural waste input, vegetation cover) was the main influence on the long-term changes of coastal SPM in Hainan Island, particularly evident in typical tropical ecosystems affected by aquaculture, coastal engineering, and changes in coastal green vegetation. Compared to other typical ecosystems around the globe, the overall health status of SPM along the coast wetlands of Hainan is considered satisfactory. These findings not only establish a robust remote sensing model for long-term SPM monitoring along the coast of Hainan Island, but also provide comprehensive insights into SPM dynamics, thereby contributing to the formulation of future coastal zone management policies.
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Affiliation(s)
- Rong Zhong
- State Key Laboratory of Tropical Oceanography and Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Songlin Liu
- State Key Laboratory of Tropical Oceanography and Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China
| | - Shiquan Chen
- Hainan Academy of Ocean and Fisheries Sciences, Haikou, 570100, China.
| | - Linhong Zhao
- State Key Laboratory of Tropical Oceanography and Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Dingtian Yang
- State Key Laboratory of Tropical Oceanography and Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Sanya Institute of Ocean Eco-Environmental Engineering, Sanya, 572000, China.
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3
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Severati A, Nordborg FM, Heyward A, Abdul Wahab MA, Brunner CA, Montalvo-Proano J, Negri AP. The AutoSpawner system - Automated ex situ spawning and fertilisation of corals for reef restoration. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 366:121886. [PMID: 39029173 DOI: 10.1016/j.jenvman.2024.121886] [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: 02/28/2024] [Revised: 07/11/2024] [Accepted: 07/13/2024] [Indexed: 07/21/2024]
Abstract
The restoration of reefs damaged by global and local pressures remains constrained by the scale of intervention currently feasible. Traditional methods for ex situ sexual propagation of corals produce limited materials, typically of limited genetic diversity and only sufficient for small field trials. The development and validation of new technologies to upscale and automate coral propagation is required to achieve logistically and financially feasible reef restoration at ecologically relevant scales. To address the need for upscaled production of genetically diverse material for use in reef restoration we designed an automated system (the AutoSpawner) for harvesting, fertilising and washing gametes from tropical broadcast-spawning corals. The system includes a novel high density dynamic fertilisation process, which enables the production of large numbers of fertilised coral eggs (>7 million per night for highly fecund species) without any downstream negative effects on larval quality. The functionality of the system and the quality of the produced larvae was assessed using multiple species from two coral families (Acroporidae and Merulinidae) across a range of spawning and gamete characteristics. We present the schematics and protocols required for automated sexual propagation of high-quality coral larvae using this novel system; and demonstrate that the time demands, and labour costs, associated with traditional manual-based sexual propagation of corals can be reduced by up to 113-fold using the AutoSpawner.
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Affiliation(s)
- Andrea Severati
- Australian Institute of Marine Science, Townsville, 4810, Queensland, Australia; The National Sea Simulator, AIMS, Townsville, 4810, Queensland, Australia
| | - F Mikaela Nordborg
- Australian Institute of Marine Science, Townsville, 4810, Queensland, Australia.
| | - Andrew Heyward
- Australian Institute of Marine Science, Crawley, 6009, Western Australia, Australia
| | | | | | | | - Andrew P Negri
- Australian Institute of Marine Science, Townsville, 4810, Queensland, Australia
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4
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Page CE, Anderson E, Ainsworth TD. Building living systematic reviews and reporting standards for comparative microscopic analysis of white diseases in hard corals. Ecol Evol 2024; 14:e11616. [PMID: 38975266 PMCID: PMC11224507 DOI: 10.1002/ece3.11616] [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: 09/24/2023] [Revised: 06/04/2024] [Accepted: 06/10/2024] [Indexed: 07/09/2024] Open
Abstract
Over the last 4 decades, coral disease research has continued to provide reports of diseases, the occurrence and severity of disease outbreaks and associated disease signs. Histology using systematic protocols is a gold standard for the microscopic assessment of diseases in veterinary and medical research, while also providing valuable information on host condition. However, uptake of histological analysis for coral disease remains limited. Increasing disease outbreaks on coral reefs as human impacts intensify highlights a need to understand the use of histology to date in coral disease research. Here, we apply a systematic approach to collating, mapping and reviewing histological methods used to study coral diseases with 'white' signs (i.e., white diseases) in hard coral taxa and map research effort in this field spanning study design, sample processing and analysis in the 33 publications identified between 1984 and 2022. We find that studies to date have not uniformly detailed methodologies, and terminology associated with reporting and disease description is inconsistent between studies. Combined these limitations reduce study repeatability, limiting the capacity for researchers to compare disease reports. A primary outcome of this study is the provision of transparent and repeatable protocols for systematically reviewing literature associated with white diseases of hard coral taxa, and development of recommendations for standardised reporting procedures with the aim of increasing uptake of histology in addition to allowing for ongoing comparative analysis through living systematic reviews for the coral disease field.
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Affiliation(s)
- C. E. Page
- School of Biological, Earth and Environmental Sciences (BEES)University of New South Wales (UNSW)KensingtonNew South WalesAustralia
| | - E. Anderson
- College of Science and EngineeringFlinders UniversityBedford ParkSouth AustraliaAustralia
| | - T. D. Ainsworth
- School of Biological, Earth and Environmental Sciences (BEES)University of New South Wales (UNSW)KensingtonNew South WalesAustralia
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5
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Mellin C, Brown S, Cantin N, Klein-Salas E, Mouillot D, Heron SF, Fordham DA. Cumulative risk of future bleaching for the world's coral reefs. SCIENCE ADVANCES 2024; 10:eadn9660. [PMID: 38924396 PMCID: PMC11204209 DOI: 10.1126/sciadv.adn9660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Accepted: 05/17/2024] [Indexed: 06/28/2024]
Abstract
Spatial and temporal patterns of future coral bleaching are uncertain, hampering global conservation efforts to protect coral reefs against climate change. Our analysis of daily projections of ocean warming establishes the severity, annual duration, and onset of severe bleaching risk for global coral reefs this century, pinpointing vital climatic refugia. We show that low-latitude coral regions are most vulnerable to thermal stress and will experience little reprieve from climate mitigation. By 2080, coral bleaching is likely to start on most reefs in spring, rather than late summer, with year-round bleaching risk anticipated to be high for some low-latitude reefs regardless of global efforts to mitigate harmful greenhouse gasses. By identifying Earth's reef regions that are at lowest risk of accelerated bleaching, our results will prioritize efforts to limit future loss of coral reef biodiversity.
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Affiliation(s)
- Camille Mellin
- The Environment Institute and School of Biological Sciences, University of Adelaide, Adelaide, SA 5005, Australia
| | - Stuart Brown
- The Environment Institute and School of Biological Sciences, University of Adelaide, Adelaide, SA 5005, Australia
| | - Neal Cantin
- Australian Institute of Marine Science, Townsville, QLD, Australia
| | | | - David Mouillot
- MARBEC, Univ Montpellier, CNRS, IFREMER, IRD, Montpellier, France
- Institut Universitaire de France, IUF, Paris 75231, France
| | - Scott F. Heron
- Physics and Marine Geophysical Laboratory, College of Science and Engineering, James Cook University, Townsville, QLD, Australia
| | - Damien A. Fordham
- The Environment Institute and School of Biological Sciences, University of Adelaide, Adelaide, SA 5005, Australia
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6
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Jones NP, Gilliam DS. Temperature and local anthropogenic pressures limit stony coral assemblage viability in southeast Florida. MARINE POLLUTION BULLETIN 2024; 200:116098. [PMID: 38310721 DOI: 10.1016/j.marpolbul.2024.116098] [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: 09/12/2023] [Revised: 01/07/2024] [Accepted: 01/28/2024] [Indexed: 02/06/2024]
Abstract
Climate change is viewed as the primary threat to coral reefs, with local pressures exacerbating coral cover decline. The consensus is that improving water quality may increase resilience, but disentangling water quality and temperature impacts is difficult. We used distance-based linear models and random forests to analyze spatiotemporal variation in benthic community structure and interannual changes in the coral assemblage, in relation to specific environmental metrics in Southeast Florida. Temperature accounted for most of the variation, recruitment doubled and interannual increases in coral abundance tripled when mean annual temperature reached 27 °C, until maximum temperatures exceeded 31 °C. Benefits associated with warmer temperatures were negated by poor water quality, as nutrient enrichment was related to increased macroalgal cover, reduced coral recruitment and higher coral partial mortality. We suggest reducing local pressures will contribute to reduced macroalgae and enhance coral recovery, but that temperature is the predominant influence on coral assemblages.
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Affiliation(s)
- Nicholas P Jones
- National Coral Reef Institute, Halmos College of Arts and Sciences, Nova Southeastern University, 8000 N Ocean Drive, Dania Beach, FL 33004, USA.
| | - David S Gilliam
- National Coral Reef Institute, Halmos College of Arts and Sciences, Nova Southeastern University, 8000 N Ocean Drive, Dania Beach, FL 33004, USA
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7
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Selmoni O, Bay LK, Exposito-Alonso M, Cleves PA. Finding genes and pathways that underlie coral adaptation. Trends Genet 2024; 40:213-227. [PMID: 38320882 DOI: 10.1016/j.tig.2024.01.003] [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: 10/09/2023] [Revised: 01/08/2024] [Accepted: 01/10/2024] [Indexed: 02/08/2024]
Abstract
Mass coral bleaching is one of the clearest threats of climate change to the persistence of marine biodiversity. Despite the negative impacts of bleaching on coral health and survival, some corals may be able to rapidly adapt to warming ocean temperatures. Thus, a significant focus in coral research is identifying the genes and pathways underlying coral heat adaptation. Here, we review state-of-the-art methods that may enable the discovery of heat-adaptive loci in corals and identify four main knowledge gaps. To fill these gaps, we describe an experimental approach combining seascape genomics with CRISPR/Cas9 gene editing to discover and validate heat-adaptive loci. Finally, we discuss how information on adaptive genotypes could be used in coral reef conservation and management strategies.
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Affiliation(s)
- Oliver Selmoni
- Department of Embryology, Carnegie Institution for Science, Baltimore, MD 21218, USA; Department of Plant Biology, Carnegie Institution for Science, Stanford, CA 94305, USA.
| | - Line K Bay
- Reef Recovery, Adaptation, and Restoration, Australian Institute of Marine Science; Townsville, QLD 4810, Australia
| | - Moises Exposito-Alonso
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA 94305, USA; Department of Biology, Stanford University, Stanford, CA 94305, USA; Department of Global Ecology, Carnegie Institution for Science, Stanford, CA 94305, USA.
| | - Phillip A Cleves
- Department of Embryology, Carnegie Institution for Science, Baltimore, MD 21218, USA; Department of Biology, Johns Hopkins University, Baltimore, MD 21218, USA.
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8
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Steibl S, Kench PS, Young HS, Wegmann AS, Holmes ND, Bunbury N, Teavai-Murphy TH, Davies N, Murphy F, Russell JC. Rethinking atoll futures: local resilience to global challenges. Trends Ecol Evol 2024; 39:258-266. [PMID: 38114338 DOI: 10.1016/j.tree.2023.11.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 11/08/2023] [Accepted: 11/10/2023] [Indexed: 12/21/2023]
Abstract
Atoll islands are often perceived as inevitably lost due to rising sea levels. However, unlike other islands, atoll islands are dynamic landforms that have evolved, at least historically, to vertically accrete at a pace commensurate with changing sea levels. Rather than atoll islands' low elevation per se, the impairment of natural accretion processes is jeopardising their persistence. While global marine impacts are deteriorating coral reefs, local impacts also significantly affect accretion, together potentially tipping the scales toward atoll island erosion. Maintaining atoll island accretion requires intact sediment generation on coral reefs, unobstructed sediment transport from reef to island, and available vegetated deposition sites on the island. Ensuring the persistence of atoll islands must include global greenhouse gas emission reduction and local restoration of accretion processes.
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Affiliation(s)
- Sebastian Steibl
- School of Biological Sciences, University of Auckland, Auckland, New Zealand.
| | - Paul S Kench
- Department of Geography, National University of Singapore, Singapore
| | - Hillary S Young
- Ecology, Evolution and Marine Biology, University of California, Santa Barbara, CA, USA
| | | | | | - Nancy Bunbury
- Seychelles Islands Foundation, Victoria, Mahé, Seychelles; Centre for Ecology and Conservation, University of Exeter, Exeter, UK
| | | | - Neil Davies
- Tetiaroa Society, Tetiaroa, French Polynesia; Gump South Pacific Research Station, University of California, Berkeley, CA, USA
| | | | - James C Russell
- School of Biological Sciences, University of Auckland, Auckland, New Zealand; School of Biological Sciences, University of Aberdeen, Aberdeen, UK.
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9
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Ceccarelli DM, Evans RD, Logan M, Jones GP, Puotinen M, Petus C, Russ GR, Srinivasan M, Williamson DH. Physical, biological and anthropogenic drivers of spatial patterns of coral reef fish assemblages at regional and local scales. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 904:166695. [PMID: 37660823 DOI: 10.1016/j.scitotenv.2023.166695] [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: 08/19/2022] [Revised: 08/16/2023] [Accepted: 08/28/2023] [Indexed: 09/05/2023]
Abstract
Species abundance, diversity and community assemblage structure are determined by multiple physical, habitat and management drivers that operate across multiple spatial scales. Here we used a multi-scale coral reef monitoring dataset to examine regional and local differences in the abundance, species richness and composition of fish assemblages in no-take marine reserve (NTMR) and fished zones at four island groups in the Great Barrier Reef Marine Park, Australia. We applied boosted regression trees to quantify the influence of 20 potential drivers on the coral reef fish assemblages. Reefs in two locations, Magnetic Island and the Keppel Islands, had distinctive fish assemblages and low species richness, while the Palm and Whitsunday Islands had similar species composition and higher species richness. Overall, our analyses identified several important physical (temperature, wave exposure) and biological (coral, turf, macroalgal and unconsolidated substratum cover) drivers of inshore reef fish communities, some of which are being altered by human activities. Of these, sea surface temperature (SST) was more influential at large scales, while wave exposure was important both within and between island groups. Species richness declined with increasing macroalgal cover and exposure to cyclones, and increased with SST. Species composition was most strongly influenced by mean SST and percent cover of macroalgae. There was substantial regional variation in the local drivers of spatial patterns. Although NTMR zoning influenced total fish density in some regions, it had negligible effects on fish species richness, composition and trophic structure because of the relatively small number of species targeted by the fishery. These findings show that inshore reef fishes are directly influenced by disturbances typical of the nearshore Great Barrier Reef, highlighting the need to complement global action on climate change with more targeted localised efforts to maintain or improve the condition of coral reef habitats.
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Affiliation(s)
- Daniela M Ceccarelli
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD 4811, Australia; Australian Institute of Marine Science, Townsville, QLD 4810, Australia.
| | - Richard D Evans
- Department of Biodiversity, Conservation and Attractions, Kensington, WA 6151, Australia; Oceans Institute, University of Western Australia, Crawley, WA 6009, Australia
| | - Murray Logan
- Australian Institute of Marine Science, Townsville, QLD 4810, Australia
| | - Geoffrey P Jones
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD 4811, Australia; College of Science & Engineering, James Cook University, Townsville, QLD 4811, Australia
| | - Marji Puotinen
- Australian Institute of Marine Science, Townsville, QLD 4810, Australia
| | - Caroline Petus
- Centre for Tropical Water and Aquatic System Research, James Cook University, Townsville, QLD 4811, Australia
| | - Garry R Russ
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD 4811, Australia; College of Science & Engineering, James Cook University, Townsville, QLD 4811, Australia
| | - Maya Srinivasan
- College of Science & Engineering, James Cook University, Townsville, QLD 4811, Australia; Centre for Tropical Water and Aquatic System Research, James Cook University, Townsville, QLD 4811, Australia
| | - David H Williamson
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD 4811, Australia; Great Barrier Reef Marine Park Authority, Townsville, QLD 4811, Australia
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10
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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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11
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Gove JM, Williams GJ, Lecky J, Brown E, Conklin E, Counsell C, Davis G, Donovan MK, Falinski K, Kramer L, Kozar K, Li N, Maynard JA, McCutcheon A, McKenna SA, Neilson BJ, Safaie A, Teague C, Whittier R, Asner GP. Coral reefs benefit from reduced land-sea impacts under ocean warming. Nature 2023; 621:536-542. [PMID: 37558870 PMCID: PMC10511326 DOI: 10.1038/s41586-023-06394-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 06/30/2023] [Indexed: 08/11/2023]
Abstract
Coral reef ecosystems are being fundamentally restructured by local human impacts and climate-driven marine heatwaves that trigger mass coral bleaching and mortality1. Reducing local impacts can increase reef resistance to and recovery from bleaching2. However, resource managers lack clear advice on targeted actions that best support coral reefs under climate change3 and sector-based governance means most land- and sea-based management efforts remain siloed4. Here we combine surveys of reef change with a unique 20-year time series of land-sea human impacts that encompassed an unprecedented marine heatwave in Hawai'i. Reefs with increased herbivorous fish populations and reduced land-based impacts, such as wastewater pollution and urban runoff, had positive coral cover trajectories predisturbance. These reefs also experienced a modest reduction in coral mortality following severe heat stress compared to reefs with reduced fish populations and enhanced land-based impacts. Scenario modelling indicated that simultaneously reducing land-sea human impacts results in a three- to sixfold greater probability of a reef having high reef-builder cover four years postdisturbance than if either occurred in isolation. International efforts to protect 30% of Earth's land and ocean ecosystems by 2030 are underway5. Our results reveal that integrated land-sea management could help achieve coastal ocean conservation goals and provide coral reefs with the best opportunity to persist in our changing climate.
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Affiliation(s)
- Jamison M Gove
- Pacific Islands Fisheries Science Center, National Oceanic and Atmospheric Administration (NOAA), Honolulu, HI, USA.
| | - Gareth J Williams
- School of Ocean Sciences, Bangor University, Menai Bridge, Anglesey, UK.
| | - Joey Lecky
- Pacific Islands Regional Office, National Oceanic and Atmospheric Administration, Honolulu, HI, USA
| | - Eric Brown
- National Park of American Samoa, Pago Pago, American Samoa, USA
| | | | - Chelsie Counsell
- Cooperative Institute for Marine and Atmospheric Research, Honolulu, HI, USA
| | - Gerald Davis
- Pacific Islands Regional Office, National Oceanic and Atmospheric Administration, Honolulu, HI, USA
| | - Mary K Donovan
- Center for Global Discovery and Conservation Science, Arizona State University, Hilo, HI, USA
- School of Geographical Sciences and Urban Planning, Arizona State University, Tempe, AZ, USA
| | | | | | - Kelly Kozar
- National Park Service, Pacific Island Network Inventory and Monitoring, Hawai'i National Park, HI, USA
| | - Ning Li
- Department of Ocean and Resources Engineering, University of Hawai'i at Mānoa, Honolulu, HI, USA
| | | | - Amanda McCutcheon
- National Park Service, Pacific Island Network Inventory and Monitoring, Hawai'i National Park, HI, USA
| | - Sheila A McKenna
- National Park Service, Pacific Island Network Inventory and Monitoring, Hawai'i National Park, HI, USA
| | | | - Aryan Safaie
- Graduate School of Oceanography, University of Rhode Island, Narragansett, RI, USA
| | | | | | - Gregory P Asner
- Center for Global Discovery and Conservation Science, Arizona State University, Hilo, HI, USA
- School of Ocean Futures, Arizona State University, Hilo, HI, USA
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12
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Lachs L, Donner SD, Mumby PJ, Bythell JC, Humanes A, East HK, Guest JR. Emergent increase in coral thermal tolerance reduces mass bleaching under climate change. Nat Commun 2023; 14:4939. [PMID: 37607913 PMCID: PMC10444816 DOI: 10.1038/s41467-023-40601-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Accepted: 08/01/2023] [Indexed: 08/24/2023] Open
Abstract
Recurrent mass bleaching events threaten the future of coral reefs. To persist under climate change, corals will need to endure progressively more intense and frequent marine heatwaves, yet it remains unknown whether their thermal tolerance can keep pace with warming. Here, we reveal an emergent increase in the thermal tolerance of coral assemblages at a rate of 0.1 °C/decade for a remote Pacific coral reef system. This led to less severe bleaching impacts than would have been predicted otherwise, indicating adaptation, acclimatisation or shifts in community structure. Using future climate projections, we show that if thermal tolerance continues to rise over the coming century at the most-likely historic rate, substantial reductions in bleaching trajectories are possible. High-frequency bleaching can be fully mitigated at some reefs under low-to-middle emissions scenarios, yet can only be delayed under high emissions scenarios. Collectively, our results indicate a potential ecological resilience to climate change, but still highlight the need for reducing carbon emissions in line with Paris Agreement commitments to preserve coral reefs.
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Affiliation(s)
- Liam Lachs
- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, UK.
- Institute of Resources, Environment and Sustainability, and Department of Geography, University of British Columbia, Vancouver, BC, Canada.
| | - Simon D Donner
- Institute of Resources, Environment and Sustainability, and Department of Geography, University of British Columbia, Vancouver, BC, Canada
| | - Peter J Mumby
- Marine Spatial Ecology Lab, School of Biological Sciences, The University of Queensland, St Lucia, QLD, Australia
- Palau International Coral Reef Center, Koror, Palau
| | - John C Bythell
- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Adriana Humanes
- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Holly K East
- Department of Geography and Environmental Sciences, Northumbria University, Newcastle upon Tyne, UK
| | - James R Guest
- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, UK
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Bay LK, Gilmour J, Muir B, Hardisty PE. Management approaches to conserve Australia's marine ecosystem under climate change. Science 2023; 381:631-636. [PMID: 37561873 DOI: 10.1126/science.adi3023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 06/23/2023] [Indexed: 08/12/2023]
Abstract
Australia's coastal marine ecosystems have a deep cultural significance to Indigenous Australians, include multiple World Heritage sites, and support the nation's rapidly growing blue economy. Yet, increasing local pressures and global climate change are expected to undermine the biological, social, cultural, and economic value of these ecosystems within a human generation. Mitigating the causes of climate change is the most urgent action to secure their future; however, conventional and new management actions will play roles in preserving ecosystem function and value until that is achieved. This includes strategies codeveloped with Indigenous Australians that are guided by traditional ecological knowledge and a modeling and decision support framework. We provide examples of developments at one of Australia's most iconic ecosystems, the Great Barrier Reef, where recent, large block funding supports research, governance, and engagement to accelerate the development of tools for management under climate change.
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Affiliation(s)
- Line K Bay
- Australian Institute of Marine Science, Townsville, QLD, Australia
| | - James Gilmour
- Australian Institute of Marine Science, Townsville, QLD, Australia
| | - Bob Muir
- Australian Institute of Marine Science, Townsville, QLD, Australia
| | - Paul E Hardisty
- Australian Institute of Marine Science, Townsville, QLD, Australia
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14
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Page CE, Ainsworth TD, Leggat W, Egan S, Gupta AS, Raoult V, Gaston TF. Localising terrestrially derived pollution inputs to threatened near-shore coral reefs through stable isotope, water quality and oceanographic analysis. MARINE POLLUTION BULLETIN 2023; 193:115193. [PMID: 37399735 DOI: 10.1016/j.marpolbul.2023.115193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2023] [Revised: 05/10/2023] [Accepted: 06/15/2023] [Indexed: 07/05/2023]
Abstract
Near-shore coral reefs are at high-risk of exposure to pollution from terrestrial activities. Pollution impacts can vary with site-specific factors that span sources, rainfall and oceanographic characteristics. To effectively manage pollution, we need to understand how these factors interact. In this study, we detect terrestrially derived nutrient inputs on near-shore reefs at Norfolk Island, South Pacific by analysis of dissolved inorganic nitrogen (DIN) and stable isotopes. When compared to a reef site with predominantly oceanic inputs, we found that both the lagoon and a small reef adjacent to a catchment have signatures of human-derived DIN shown through depleted δ15N signatures in macroalgae. We find pollution exposure of reef sites is associated with known and unknown sources, rainfall and mixing of water with the open ocean. In characterising exposure of reef sites we highlight the role of site-specific context in influencing pollution exposure for benthic communities even in remote island systems.
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Affiliation(s)
- C E Page
- School of Biological, Earth and Environmental Sciences (BEES), UNSW, Kensington, NSW 2033, Australia.
| | - T D Ainsworth
- School of Biological, Earth and Environmental Sciences (BEES), UNSW, Kensington, NSW 2033, Australia
| | - W Leggat
- University of Newcastle, School of Environmental and Life Sciences, University Dr, Callaghan, NSW 2308, Australia
| | - S Egan
- School of Biological, Earth and Environmental Sciences (BEES), UNSW, Kensington, NSW 2033, Australia
| | - A Sen Gupta
- School of Biological, Earth and Environmental Sciences (BEES), UNSW, Kensington, NSW 2033, Australia
| | - V Raoult
- University of Newcastle, School of Environmental and Life Sciences, University Dr, Callaghan, NSW 2308, Australia; Marine Ecology Group, School of Natural Sciences, Macquarie University, North Ryde, NSW 2113, Australia
| | - T F Gaston
- University of Newcastle, School of Environmental and Life Sciences, University Dr, Callaghan, NSW 2308, Australia
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15
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Mason RAB, Bozec YM, Mumby PJ. Setting sustainable limits on anchoring to improve the resilience of coral reefs. MARINE POLLUTION BULLETIN 2023; 189:114721. [PMID: 36907169 DOI: 10.1016/j.marpolbul.2023.114721] [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: 11/10/2022] [Revised: 02/05/2023] [Accepted: 02/07/2023] [Indexed: 06/18/2023]
Abstract
Boat anchoring is common at coral reefs that have high economic or social value, but anchoring has received relatively little attention in reef resilience studies. We developed an individual-based model of coral populations and simulated the effects of anchor damage over time. The model allowed us to estimate the carrying capacity of anchoring for four different coral assemblages and different starting levels of coral cover. The carrying capacity of small to medium-sized recreational vessels across these four assemblages was between 0 and 3.1 anchor strikes ha-1 day-1. In a case study of two Great Barrier Reef archipelagos, we modelled the benefits of anchoring mitigation under bleaching regimes expected for four climate scenarios. The partial mitigation of even a very mild anchoring incidence (1.17 strikes ha-1 day-1) resulted in median coral gains of 2.6-7.7 % absolute cover under RCP2.6, though benefits varied temporally and depended on the Atmosphere-Ocean General Circulation Model used.
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Affiliation(s)
- Robert A B Mason
- School of Biological Sciences, University of Queensland, St. Lucia, Queensland 4072, Australia.
| | - Yves-Marie Bozec
- School of Biological Sciences, University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Peter J Mumby
- School of Biological Sciences, University of Queensland, St. Lucia, Queensland 4072, Australia
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16
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Ouédraogo DY, Mell H, Perceval O, Burga K, Domart-Coulon I, Hédouin L, Delaunay M, Guillaume MMM, Castelin M, Calvayrac C, Kerkhof O, Sordello R, Reyjol Y, Ferrier-Pagès C. What are the toxicity thresholds of chemical pollutants for tropical reef-building corals? A systematic review. ENVIRONMENTAL EVIDENCE 2023; 12:4. [PMID: 39294817 PMCID: PMC11378836 DOI: 10.1186/s13750-023-00298-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Accepted: 02/22/2023] [Indexed: 09/21/2024]
Abstract
BACKGROUND Tropical coral reefs cover only ca. 0.1% of the Earth's surface but harbour exceptional marine biodiversity and provide vital ecosystem services to millions of people living nearby. They are currently threatened by global (e.g. climate change) and local (e.g. chemical pollution) stressors that interact in multiple ways. While global stressors cannot be mitigated by local actions alone, local stressors can be reduced through ecosystem management. Here, we aimed to systematically review experimental studies assessing the toxicity of chemical pollutants to tropical reef-building corals to generate accessible and usable knowledge and data that can be used to calculate measurement endpoints in ecological risk assessment. From the quantitative estimates of effects, we determined toxicity thresholds as the highest exposures tested at which no statistically significant adverse effects were observed, and we compared them to regulatory predicted no effect concentrations for the protection of marine organisms, to assess whether these reference values are indeed protective of corals. METHODS The evidence was taken from a systematic map of the impacts of chemicals arising from human activity on tropical reef-building corals published in 2021. All studies in the map database corresponding to the knowledge cluster "Evidence on the ecotoxicological effects of chemicals on corals" were selected. To identify subsequently published literature, the search was updated using a subset of the search string used for the systematic map. Titles, abstracts and full-texts were screened according to the criteria defining the selected cluster of the map. Because the eligibility criteria for the systematic review are narrower than the criteria used to define the cluster in the systematic map, additional screening was performed. Studies included were critically appraised and each study was rated as low, unclear, medium, or high risk of bias. Data were extracted from the studies and synthesised according to a strategy dependent on the type of exposure and outcome. REVIEW FINDINGS The systematic review reports the known effects of chemical exposures on corals from 847 studies corresponding to 181 articles. A total of 697 studies (161 articles) were included in the quantitative synthesis and 150 studies (50 articles) in the narrative synthesis of the findings. The quantitative synthesis records the effects of 2706 exposure concentrations-durations of 164 chemicals or mixtures of chemicals, and identifies 105 toxicity thresholds corresponding to 56 chemicals or mixtures of chemicals. When toxicity thresholds were compared to reference values set for the protection of marine organisms by environmental agencies, the reference values appear to be protective of corals for all but three chemicals assessed: the metal copper and the pesticides diuron and irgarol 1051. CONCLUSIONS This open-access database of known ecotoxicological effects of chemical exposures on corals can assist managers in the ecological risk assessment of chemicals, by allowing easy determination of various ecotoxicological thresholds. Several limitations of the toxicity tests synthesised here were noted (in particular the lack of measurement of effective concentrations for more than half of the studies). Overall, most of the currently available data on coral toxicity should be replicated independently and extended to corals from less studied geographical regions and functional groups.
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Affiliation(s)
- Dakis-Yaoba Ouédraogo
- Direction de L'Expertise, Muséum National d'Histoire Naturelle (MNHN), 75005, Paris, France.
| | - Hugo Mell
- UMS Patrimoine Naturel (PatriNat), OFB-MNHN-CNRS, 75005, Paris, France
| | - Olivier Perceval
- Office Français de la Biodiversité (OFB), 94300, Vincennes, France
| | - Karen Burga
- French Agency for Food, Environmental and Occupational Health & Safety (ANSES), 94701, Maisons-Alfort Cedex, France
| | - Isabelle Domart-Coulon
- Laboratoire Molécules de Communication et Adaptation des Microorganismes (MCAM), UMR 7245, CNRS-Muséum National d'Histoire Naturelle (MNHN), 75005, Paris, France
| | - Laetitia Hédouin
- Laboratoire d'Excellence CORAIL, 66860, Perpignan, France
- USR 3278 CRIOBE, PSL Université Paris : EPHE-UPVD-CNRS, 98729, Papetoai, Mo'orea, French Polynesia
| | - Mathilde Delaunay
- UMS Patrimoine Naturel (PatriNat), OFB-MNHN-CNRS, 75005, Paris, France
| | - Mireille M M Guillaume
- Laboratoire d'Excellence CORAIL, 66860, Perpignan, France
- Laboratoire de Biologie Des Organismes et Ecosystèmes Aquatiques (BOrEA), Muséum National d'Histoire Naturelle-CNRS - SorbonneU - IRD - UCN - UA EcoFunc - Aviv, 75005, Paris, France
| | - Magalie Castelin
- Institut de Systématique, Evolution, Biodiversité (ISYEB), Muséum National d'Histoire Naturelle - CNRS - Sorbonne Université - EPHE - Université des Antilles, 75005, Paris, France
| | - Christophe Calvayrac
- Biocapteurs Analyses Environnement, University of Perpignan via Domitia, 66000, Perpignan, France
- Laboratoire de Biodiversité et Biotechnologies Microbiennes (LBBM), Sorbonne Universités - CNRS, 66650, Banyuls Sur Mer, France
| | - Odile Kerkhof
- French Agency for Food, Environmental and Occupational Health & Safety (ANSES), 94701, Maisons-Alfort Cedex, France
| | - Romain Sordello
- UMS Patrimoine Naturel (PatriNat), OFB-MNHN-CNRS, 75005, Paris, France
| | - Yorick Reyjol
- UMS Patrimoine Naturel (PatriNat), OFB-MNHN-CNRS, 75005, Paris, France
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17
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Canning AD, Smart JCR, Dyke J, Curwen G, Hasan S, Waltham NJ. Constructed Wetlands Suitability for Sugarcane Profitability, Freshwater Biodiversity and Ecosystem Services. ENVIRONMENTAL MANAGEMENT 2023; 71:304-320. [PMID: 36269373 PMCID: PMC9892086 DOI: 10.1007/s00267-022-01734-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Accepted: 10/02/2022] [Indexed: 06/16/2023]
Abstract
Freshwater ecosystems, such as wetlands, are among the most impacted by agricultural expansion and intensification through extensive drainage and pollution. There is a pressing need to identify ways of managing agricultural landscapes to ensure food and water security without jeopardising biodiversity and other environmental benefits. Here we examine the potential fish biodiversity and landholder financial benefits arising from the integration of constructed lagoons to improve drainage, flow regulation and habitat connectivity within a sugarcane dominated catchment in north Queensland, Australia. A hybrid approach was used, combining the findings of both fish ecological surveys and a financial cost-benefit analysis. We found that the constructed lagoons supported at least 36 native freshwater fishes (over half of all native freshwater fishes in the region), owing to their depth, vegetated margins, moderate water quality and high connectivity to the Tully River. In addition to biodiversity benefits, we estimated that surrounding sugarcane farms would have financially benefited from reduced flooding of cropland and the elevation of low-lying cropland with deposited spoil excavated from lagoon construction. Improved drainage and flow regulation allowed for improvement in sugarcane yield and elevated land increased gross margins from extending the length of the cane production cycle or enabling a switch from cattle grazing to cane production. Restoring or creating wetlands to reduce flooding in flood-prone catchments is a globally applicable model that could improve both agricultural productivity and aquatic biodiversity, while potentially increasing farm income by attracting payments for provision of ecosystem services.
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Affiliation(s)
- Adam D Canning
- Centre for Tropical Water and Aquatic Ecosystem Research (TropWATER), James Cook University, 1 James Cook Drive, Townsville, Queensland, 4811, Australia.
| | - James C R Smart
- School of Environment and Science, Griffith University, 170 Kessels Road, Nathan, Queensland, 4111, Australia
- Australian Rivers Institute, Griffith University, 170 Kessels Road, Nathan, Queensland, 4111, Australia
| | - Joshua Dyke
- Australian Rivers Institute, Griffith University, 170 Kessels Road, Nathan, Queensland, 4111, Australia
| | - Graeme Curwen
- Australian Rivers Institute, Griffith University, 170 Kessels Road, Nathan, Queensland, 4111, Australia
| | - Syezlin Hasan
- Australian Rivers Institute, Griffith University, 170 Kessels Road, Nathan, Queensland, 4111, Australia
| | - Nathan J Waltham
- Centre for Tropical Water and Aquatic Ecosystem Research (TropWATER), James Cook University, 1 James Cook Drive, Townsville, Queensland, 4811, Australia
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18
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Carbery M, Herb F, Reynes J, Pham CK, Fong WK, Lehner R. How small is the big problem? Small microplastics <300 μm abundant in marine surface waters of the Great Barrier Reef Marine Park. MARINE POLLUTION BULLETIN 2022; 184:114179. [PMID: 36206615 DOI: 10.1016/j.marpolbul.2022.114179] [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: 07/26/2022] [Revised: 09/22/2022] [Accepted: 09/23/2022] [Indexed: 06/16/2023]
Abstract
Particle size plays an important role in determining the behaviour, fate and effects of microplastics (MPs), yet little is known about MPs <300 μm in aquatic environments. Therefore, we performed the first assessment of MPs in marine surface waters around the Whitsunday Islands region of the Great Barrier Reef Marine Park, Australia, to test for the presence of small MPs (50-300 μm) in-situ. Using a modified manta net, we demonstrate that MPs were present in all marine surface water samples, with a mean sea surface concentration of 0.23 ± 0.03 particles m-3. Microplastics were mainly blue, clear and black fibres and fragments, consisting of polyethylene terephthalate, high-density polyethylene and polypropylene plastic polymers. Tourism and marine recreation were considered the major contributing sources of MPs to surface waters around the Whitsunday Islands. Between 10 and 124 times the number of MPs exist in the 50 μm-300 μm size class, compared with the 1 mm-5 mm size range. This finding indicates that the global abundance of small MPs in marine surface waters is grossly underestimated and warrants further investigation. Research into the occurrence, characteristics and environmental fate of MPs <300 μm is needed to improve our understanding of the cumulative threats facing valuable ecosystems due to this smaller, potentially more hazardous size class.
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Affiliation(s)
- Maddison Carbery
- School of Environmental and Life Sciences, University of Newcastle, Callaghan 2308, NSW, Australia
| | - Frithjof Herb
- School of Environmental and Life Sciences, University of Newcastle, Callaghan 2308, NSW, Australia
| | - Julien Reynes
- Institute of Geological Sciences, University of Bern, CH-3012 Bern, Switzerland; Institute of Earth Sciences, University of Lausanne, Géopolis, Quartier Mouline, 1015 Lausanne, Switzerland
| | - Christopher K Pham
- Instituto de Investigação em Ciências do Mar - IMAR/OKEANOS, Universidade dos Açores, 9900-138 Horta, Portugal
| | - Wye-Khay Fong
- School of Environmental and Life Sciences, University of Newcastle, Callaghan 2308, NSW, Australia.
| | - Roman Lehner
- Sail and Explore Association, Kramgasse 18, 3011 Bern, Switzerland.
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19
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Fish community structure and dynamics are insufficient to mediate coral resilience. Nat Ecol Evol 2022; 6:1700-1709. [PMID: 36192541 DOI: 10.1038/s41559-022-01882-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 08/15/2022] [Indexed: 11/08/2022]
Abstract
Coral reefs are being impacted by myriad stressors leading to drastic changes to their structure and function. Fishes play essential roles in driving ecosystem processes on coral reefs but the extent to which these processes are emergent at temporal or ecosystem scales or otherwise masked by other drivers (for example, climatic events and crown-of-thorns starfish outbreaks) is poorly understood. Using time series data on fish community composition and coral and macroalgae percentage cover between 2006 and 2017 from 57 sites around Mo'orea, Polynesia, we found that fish community diversity predicts temporal stability in fish biomass but did not translate to temporal stability of coral cover. Furthermore, we found limited evidence of directional influence of fish on coral dynamics at temporal and ecosystem scales and no evidence that fish mediate coral recovery rate from disturbance. Our findings suggest that coral reef fisheries management will benefit from maintaining fish diversity but that this level of management is unlikely to strongly mediate coral loss or recovery over time.
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20
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Abeysiri Wickrama Liyanaarachchige PT, Fisher R, Thompson H, Menendez P, Gilmour J, McGree JM. Adaptive monitoring of coral health at Scott Reef where data exhibit nonlinear and disturbed trends over time. Ecol Evol 2022; 12:e9233. [PMID: 36110888 PMCID: PMC9465202 DOI: 10.1002/ece3.9233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 07/22/2022] [Accepted: 07/28/2022] [Indexed: 11/23/2022] Open
Abstract
Time series data are often observed in ecological monitoring. Frequently, such data exhibit nonlinear trends over time potentially due to complex relationships between observed and auxiliary variables, and there may also be sudden declines over time due to major disturbances. This poses substantial challenges for modeling such data and also for adaptive monitoring. To address this, we propose methods for finding adaptive designs for monitoring in such settings. This work is motivated by a monitoring program that has been established at Scott Reef; a coral reef off the Western coast of Australia. Data collected for monitoring the health of Scott Reef are considered, and semiparametric and interrupted time series modeling approaches are adopted to describe how these data vary over time. New methods are then proposed that enable adaptive monitoring designs to be found based on such modeling approaches. These methods are then applied to find future monitoring designs at Scott Reef where it was found that future information gain is expected to be similar across a variety of different sites, suggesting that no particular location needs to be prioritized at Scott Reef for the next monitoring phase. In addition, it was found that omitting some sampling sites/reef locations was possible without substantial loss in expected information gain, depending upon the disturbances that were observed. The resulting adaptive designs are used to form recommendations for future monitoring in this region, and for reefs where changes in the current monitoring practices are being sought. As the methods used and developed throughout this study are generic in nature, this research has the potential to improve ecological monitoring more broadly where complex data are being collected over time.
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Affiliation(s)
- Pubudu Thilan Abeysiri Wickrama Liyanaarachchige
- School of Mathematical Sciences, Faculty of ScienceQueensland University of Technology (QUT)BrisbaneQueenslandAustralia
- Australian Research Council Centre of Excellence for Mathematical and Statistical Frontiers (ACEMS)BrisbaneQueenslandAustralia
- Centre for Data Science, Queensland University of TechnologyBrisbaneQueenslandAustralia
- Department of MathematicsUniversity of RuhunaMataraSri Lanka
| | - Rebecca Fisher
- Australian Institute of Marine ScienceCrawleyWestern AustraliaAustralia
- Oceans InstituteUniversity of Western AustraliaCrawleyWestern AustraliaAustralia
| | - Helen Thompson
- School of Mathematical Sciences, Faculty of ScienceQueensland University of Technology (QUT)BrisbaneQueenslandAustralia
- Centre for Data Science, Queensland University of TechnologyBrisbaneQueenslandAustralia
| | - Patricia Menendez
- Department of Econometric and Business StatisticsMonash UniversityClaytonVictoriaAustralia
- Australian Institute of Marine ScienceTownsvilleQueenslandAustralia
| | - James Gilmour
- Australian Institute of Marine ScienceCrawleyWestern AustraliaAustralia
| | - James M. McGree
- School of Mathematical Sciences, Faculty of ScienceQueensland University of Technology (QUT)BrisbaneQueenslandAustralia
- Australian Research Council Centre of Excellence for Mathematical and Statistical Frontiers (ACEMS)BrisbaneQueenslandAustralia
- Centre for Data Science, Queensland University of TechnologyBrisbaneQueenslandAustralia
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21
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Devlin MJ. Coral reefs: The good and not so good news with future bright and dark spots for coral reefs through climate change. GLOBAL CHANGE BIOLOGY 2022; 28:4506-4508. [PMID: 35593317 PMCID: PMC9327719 DOI: 10.1111/gcb.16271] [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: 04/03/2022] [Revised: 04/25/2022] [Accepted: 05/11/2022] [Indexed: 06/12/2023]
Abstract
COMMENTARY ON Present and future bright and dark spots for coral reefs through climate change. This is a commentary on Sully et al., 2022, https://doi.org/10.1111/gcb.16083
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22
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Tsai CH, Sweatman HPA, Thibaut LM, Connolly SR. Volatility in coral cover erodes niche structure, but not diversity, in reef fish assemblages. SCIENCE ADVANCES 2022; 8:eabm6858. [PMID: 35704577 PMCID: PMC9200288 DOI: 10.1126/sciadv.abm6858] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 05/02/2022] [Indexed: 05/26/2023]
Abstract
The world's coral reefs are experiencing increasing volatility in coral cover, largely because of anthropogenic environmental change, highlighting the need to understand how such volatility will influence the structure and dynamics of reef assemblages. These changes may influence not only richness or evenness but also the temporal stability of species' relative abundances (temporal beta-diversity). Here, we analyzed reef fish assemblage time series from the Great Barrier Reef to show that, overall, 75% of the variance in abundance among species was attributable to persistent differences in species' long-term mean abundances. However, the relative importance of stochastic fluctuations in abundance was higher on reefs that experienced greater volatility in coral cover, whereas it did not vary with drivers of alpha-diversity. These findings imply that increased coral cover volatility decreases temporal stability in relative abundances of fishes, a transformation that is not detectable from static measures of biodiversity.
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Affiliation(s)
- Cheng-Han Tsai
- College of Science and Engineering, James Cook University, Townsville, QLD 4811, Australia
- Australian Institute of Marine Science, Townsville MC, QLD 4810, Australia
- Australian Research Council Centre of Excellence for Coral Reef Studies, Townsville, QLD 4811, Australia
| | | | - Loïc M. Thibaut
- School of Mathematics and Statistics, University of New South Wales, Sydney, NSW 2052, Australia
- Centre for Population Genomics, Garvan Institute of Medical Research and UNSW Sydney, Sydney, NSW, Australia
- Centre for Population Genomics, Murdoch Children’s Research Institute, Melbourne, VIC, Australia
| | - Sean R. Connolly
- College of Science and Engineering, James Cook University, Townsville, QLD 4811, Australia
- Australian Research Council Centre of Excellence for Coral Reef Studies, Townsville, QLD 4811, Australia
- Smithsonian Tropical Research Institute, Panama, Republic of Panama
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23
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Gilmour JP, Cook KL, Ryan NM, Puotinen ML, Green RH, Heyward AJ. A tale of two reef systems: Local conditions, disturbances, coral life histories, and the climate catastrophe. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2022; 32:e2509. [PMID: 34870357 DOI: 10.1002/eap.2509] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 05/22/2021] [Accepted: 07/26/2021] [Indexed: 06/13/2023]
Abstract
Coral reefs have evolved over millennia to survive disturbances. Yet, in just a few decades chronic local pressures and the climate catastrophe have accelerated so quickly that most coral reefs are now threatened. Rising ocean temperatures and recurrent bleaching pose the biggest threat, affecting even remote and well-managed reefs on global scales. We illustrate how coral bleaching is altering reefs by contrasting the dynamics of adjacent reef systems over more than two decades. Both reef systems sit near the edge of northwest Australia's continental shelf, have escaped chronic local pressures and are regularly affected by tropical storms and cyclones. The Scott reef system has experienced multiple bleaching events, including mass bleaching in 1998 and 2016, from which it is unlikely to fully recover. The Rowley Shoals has maintained a high cover and diversity of corals and has not yet been impacted by mass bleaching. We show how the dynamics of both reef systems were driven by a combination of local environment, exposure to disturbances and coral life history traits, and consider future shifts in community structure with ongoing climate change. We then demonstrate how applying knowledge of community dynamics at local scales can aid management strategies to slow the degradation of coral reefs until carbon emissions and other human impacts are properly managed.
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Affiliation(s)
- James P Gilmour
- The Australian Institute of Marine Science, Indian Ocean Marine Research Centre, The University of Western Australia, Crawley, Western Australia, Australia
- Oceans Institute, University of Western Australia, Crawley, Western Australia, Australia
| | - Kylie L Cook
- The Australian Institute of Marine Science, Indian Ocean Marine Research Centre, The University of Western Australia, Crawley, Western Australia, Australia
| | - Nicole M Ryan
- The Australian Institute of Marine Science, Indian Ocean Marine Research Centre, The University of Western Australia, Crawley, Western Australia, Australia
| | - Marjetta L Puotinen
- The Australian Institute of Marine Science, Indian Ocean Marine Research Centre, The University of Western Australia, Crawley, Western Australia, Australia
| | - Rebecca H Green
- Oceans Institute, University of Western Australia, Crawley, Western Australia, Australia
- ARC Centre of Excellence for Coral Reef Studies, University of Western Australia, Crawley, Western Australia, Australia
| | - Andrew J Heyward
- The Australian Institute of Marine Science, Indian Ocean Marine Research Centre, The University of Western Australia, Crawley, Western Australia, Australia
- Oceans Institute, University of Western Australia, Crawley, Western Australia, Australia
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24
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Sediment Prediction in the Great Barrier Reef using Vision Transformer with finite element analysis. Neural Netw 2022; 152:311-321. [DOI: 10.1016/j.neunet.2022.04.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 03/26/2022] [Accepted: 04/20/2022] [Indexed: 11/23/2022]
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25
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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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26
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Andrello M, Darling ES, Wenger A, Suárez‐Castro AF, Gelfand S, Ahmadia GN. A global map of human pressures on tropical coral reefs. Conserv Lett 2021. [DOI: 10.1111/conl.12858] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Affiliation(s)
- Marco Andrello
- Institute for the Study of Anthropic Impacts and Sustainability in the Marine Environment National Research Council, CNR‐IAS Rome Italy
- MARBEC Université de Montpellier Montpellier France
| | - Emily S. Darling
- Wildlife Conservation Society, Marine Program Bronx New York USA
- Department of Ecology and Evolutionary Biology University of Toronto Toronto Ontario Canada
| | - Amelia Wenger
- Wildlife Conservation Society, Marine Program Bronx New York USA
- School of Earth and Environmental Sciences University of Queensland St. Lucia Queensland Australia
- Centre for Biodiversity and Conservation Science University of Queensland St. Lucia Queensland Australia
| | - Andrés F. Suárez‐Castro
- Centre for Biodiversity and Conservation Science University of Queensland St. Lucia Queensland Australia
- Instituto de Investigación de Recursos Biológicos Alexander von Humboldt Distrito Capital Bogotá Colombia
| | | | - Gabby N. Ahmadia
- Oceans Conservation World Wildlife Fund District of Colombia Washington USA
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27
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Do Invasive Mammal Eradications from Islands Support Climate Change Adaptation and Mitigation? CLIMATE 2021. [DOI: 10.3390/cli9120172] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Climate change represents a planetary emergency that is exacerbating the loss of native biodiversity. In response, efforts promoting climate change adaptation strategies that improve ecosystem resilience and/or mitigate climate impacts are paramount. Invasive Alien Species are a key threat to islands globally, where strategies such as preventing establishment (biosecurity), and eradication, especially invasive mammals, have proven effective for reducing native biodiversity loss and can also advance ecosystem resilience and create refugia for native species at risk from climate change. Furthermore, there is growing evidence that successful eradications may also contribute to mitigating climate change. Given the cross-sector potential for eradications to reduce climate impacts alongside native biodiversity conservation, we sought to understand when conservation managers and funders explicitly sought to use or fund the eradication of invasive mammals from islands to achieve positive climate outcomes. To provide context, we first summarized available literature of the synergistic relationship between invasive species and climate change, including case studies where invasive mammal eradications served to meet climate adaptation or mitigation solutions. Second, we conducted a systematic review of the literature and eradication-related conference proceedings to identify when these synergistic effects of climate and invasive species were explicitly addressed through eradication practices. Third, we reviewed projects from four large funding entities known to support climate change solutions and/or native biodiversity conservation efforts and identified when eradications were funded in a climate change context. The combined results of our case study summary paired with systematic reviews found that, although eradicating invasive mammals from islands is an effective climate adaptation strategy, island eradications are poorly represented within the climate change adaptation and mitigation funding framework. We believe this is a lost opportunity and encourage eradication practitioners and funders of climate change adaptation to leverage this extremely effective nature-based tool into positive conservation and climate resilience solutions.
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Mariotti A, Croke J, Bartley R, Kelley SE, Ward J, Fülöp RH, Rood AH, Rood DH, Codilean AT, Wilcken K, Fifield K. Pre-development denudation rates for the Great Barrier Reef catchments derived using 10Be. MARINE POLLUTION BULLETIN 2021; 172:112731. [PMID: 34454389 DOI: 10.1016/j.marpolbul.2021.112731] [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: 01/30/2021] [Revised: 04/24/2021] [Accepted: 07/13/2021] [Indexed: 06/13/2023]
Abstract
Understanding of the pre-development, baseline denudation rates that deliver sediment to the Great Barrier Reef (GBR) has been elusive. Cosmogenic 10Be in sediment is a useful integrator of denudation rates and sediment yields averaged over large spatial and temporal scales. This study presents 10Be data from 71 sites across 11 catchments draining to the GBR: representing 80% of the GBR catchment area and provide background sediment yields for the region. Modern, short-term, sediment yields derived from suspended load concentrations are compared to the 10Be data to calculate an Accelerated Erosion Factor (AEF) that highlights denudation "hot-spots" where sediment yields have increased over the long-term background values. The AEF results show that 58% basins have higher modern sediment yields than long-term yields. The AEF is considered a useful approach to help prioritise on-ground investments in remediation and the additional measured empirical data in this paper will help support future predictive models.
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Affiliation(s)
- Apolline Mariotti
- School of Earth Science, University College Dublin, Dublin 4, Ireland; iCRAG - Irish Centre for Research in Applied Geosciences, University College Dublin, Ireland.
| | - Jacky Croke
- School of Geography, University College Dublin, Dublin 4, Ireland
| | - Rebecca Bartley
- CSIRO Land and Water, GPO Box 2583, Brisbane, QLD 4001, Australia
| | - Samuel E Kelley
- School of Earth Science, University College Dublin, Dublin 4, Ireland
| | - Jay Ward
- Department of Earth Science and Engineering, Imperial College London, London SW7 2AZ, UK
| | - Réka-Hajnalka Fülöp
- Australia's Nuclear Science and Technology Organisation (ANSTO), Lucas Heights, NSW 2234, Australia; School of Earth, Atmospheric and Life Sciences, University of Wollongong, Wollongong, NSW 2522, Australia
| | - Anna H Rood
- Department of Civil and Environmental Engineering, Imperial College London, London SW7 2AZ, UK; Department of Earth and Environmental Science & A. E. Lalonde AMS Laboratory, University of Ottawa, Ottawa, ON K1N 6N5, Canada
| | - Dylan H Rood
- Department of Earth Science and Engineering, Imperial College London, London SW7 2AZ, UK; Department of Earth and Environmental Science & A. E. Lalonde AMS Laboratory, University of Ottawa, Ottawa, ON K1N 6N5, Canada
| | - Alexandru T Codilean
- School of Earth, Atmospheric and Life Sciences, University of Wollongong, Wollongong, NSW 2522, Australia; ARC Centre of Excellence for Australian Biodiversity and Heritage (CABAH), University of Wollongong, Wollongong, NSW 2522, Australia
| | - Klaus Wilcken
- Australia's Nuclear Science and Technology Organisation (ANSTO), Lucas Heights, NSW 2234, Australia
| | - Keith Fifield
- Research School of Physics, The Australian National University, ACT 2601, Australia
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29
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Eberhard R, Coggan A, Jarvis D, Hamman E, Taylor B, Baresi U, Vella K, Dean AJ, Deane F, Helmstedt K, Mayfield H. Understanding the effectiveness of policy instruments to encourage adoption of farming practices to improve water quality for the Great Barrier Reef. MARINE POLLUTION BULLETIN 2021; 172:112793. [PMID: 34385021 DOI: 10.1016/j.marpolbul.2021.112793] [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: 01/31/2021] [Revised: 07/20/2021] [Accepted: 07/26/2021] [Indexed: 06/13/2023]
Abstract
Governments in Australia and internationally are experimenting with policy instruments to facilitate the adoption of farming practices with reduced environmental impacts. The Great Barrier Reef (Australia) is one such case, where sustained efforts over 20 years have yielded insufficient progress towards targets to reduce the impacts of agriculture on water quality in downstream marine ecosystems. We present a critical review of policy instruments as implemented in Great Barrier Reef catchments. We catalogue the evolving mix of policy instruments employed in reef programs, and examine evidence of the effectiveness of agricultural extension, financial incentives, and direct regulation of farming practices. There is little robust evidence to assess instrument effectiveness, in part due to the evolving mix of the instruments employed, weak program evaluation and heterogeneity of agricultural enterprises. We identify the need to improve the understanding of instrument fit to landholders and enterprises. We recommend a modelling approach to clarify pathways to impact and guide improved policy evaluation.
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Affiliation(s)
- Rachel Eberhard
- School of Architecture and Built Environment, Queensland University of Technology, Australia.
| | - Anthea Coggan
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), Land and Water, Brisbane, Australia
| | - Diane Jarvis
- College of Business, Law and Governance, James Cook University, Australia
| | - Evan Hamman
- School of Law, Queensland University of Technology, Australia
| | - Bruce Taylor
- Commonwealth Scientific and Industrial Research Organisation (CSIRO), Land and Water, Brisbane, Australia
| | - Umberto Baresi
- School of Architecture and Built Environment, Queensland University of Technology, Australia
| | - Karen Vella
- School of Architecture and Built Environment, Queensland University of Technology, Australia
| | - Angela J Dean
- Centre for the Environment, School of Biology and Environmental Science, Queensland University of Technology, Australia
| | - Felicity Deane
- School of Law, Queensland University of Technology, Australia
| | - Kate Helmstedt
- School of Mathematical Sciences, Queensland University of Technology, Australia
| | - Helen Mayfield
- School of Mathematical Sciences, Queensland University of Technology, Australia
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30
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Warne DJ, Crossman KA, Jin W, Mengersen K, Osborne K, Simpson MJ, Thompson AA, Wu P, Ortiz J. Identification of two‐phase recovery for interpretation of coral reef monitoring data. J Appl Ecol 2021. [DOI: 10.1111/1365-2664.14039] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- David J. Warne
- School of Mathematical Sciences Faculty of Science Queensland University of Technology Brisbane Qld. Australia
- Centre for Data Science Queensland University of Technology Brisbane Qld. Australia
- Australian Research Council Centre of Excellence for Mathematical and Statistical Frontiers Brisbane Qld. Australia
| | | | - Wang Jin
- The Kirby Institute University of New South Wales Sydney New South Wales Australia
| | - Kerrie Mengersen
- School of Mathematical Sciences Faculty of Science Queensland University of Technology Brisbane Qld. Australia
- Centre for Data Science Queensland University of Technology Brisbane Qld. Australia
- Australian Research Council Centre of Excellence for Mathematical and Statistical Frontiers Brisbane Qld. Australia
| | - Kate Osborne
- Australian Institute of Marine Science Townsville Qld. Australia
| | - Matthew J. Simpson
- School of Mathematical Sciences Faculty of Science Queensland University of Technology Brisbane Qld. Australia
- Centre for Data Science Queensland University of Technology Brisbane Qld. Australia
- Australian Research Council Centre of Excellence for Mathematical and Statistical Frontiers Brisbane Qld. Australia
| | | | - Paul Wu
- School of Mathematical Sciences Faculty of Science Queensland University of Technology Brisbane Qld. Australia
- Centre for Data Science Queensland University of Technology Brisbane Qld. Australia
- Australian Research Council Centre of Excellence for Mathematical and Statistical Frontiers Brisbane Qld. Australia
| | - Juan‐C. Ortiz
- Australian Institute of Marine Science Townsville Qld. Australia
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31
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Lesser MP. Eutrophication on Coral Reefs: What Is the Evidence for Phase Shifts, Nutrient Limitation and Coral Bleaching. Bioscience 2021. [DOI: 10.1093/biosci/biab101] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Coral reefs continue to experience extreme environmental pressure from climate change stressors, but many coral reefs are also exposed to eutrophication. It has been proposed that changes in the stoichiometry of ambient nutrients increase the mortality of corals, whereas eutrophication may facilitate phase shifts to macroalgae-dominated coral reefs when herbivory is low or absent. But are corals ever nutrient limited, and can eutrophication destabilize the coral symbiosis making it more sensitive to environmental stress because of climate change? The effects of eutrophication are confounded not just by the effects of climate change but by the presence of chemical pollutants in industrial, urban, and agricultural wastes. Because of these confounding effects, the increases in nutrients or changes in their stoichiometry in coastal environments, although they are important at the organismal and community level, cannot currently be disentangled from each other or from the more significant effects of climate change stressors on coral reefs.
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Affiliation(s)
- Michael P Lesser
- University of New Hampshire, Durham, New Hampshire, United States
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32
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McCloskey GL, Baheerathan R, Dougall C, Ellis R, Bennett FR, Waters D, Darr S, Fentie B, Hateley LR, Askildsen M. Modelled estimates of dissolved inorganic nitrogen exported to the Great Barrier Reef lagoon. MARINE POLLUTION BULLETIN 2021; 171:112655. [PMID: 34265552 DOI: 10.1016/j.marpolbul.2021.112655] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Revised: 06/15/2021] [Accepted: 06/17/2021] [Indexed: 06/13/2023]
Abstract
Measuring stream pollutant loads across the Great Barrier Reef (GBR) catchment area (GBRCA) is challenging due to the spatial extent, climate variability, changing land use and evolving land management practices, and cost. Thus, models are used to estimate baseline pollutant loads. The eWater Source modelling framework is coupled with agricultural paddock scale models and the GBR Dynamic SedNet plugin to simulate dissolved inorganic nitrogen (DIN) generation and transport processes across the GBRCA. Catchment scale monitoring of flow and loads are used to calibrate the models, and performance is assessed qualitatively and quantitatively. Modelling indicates almost half (47%) of the total modelled DIN load exported to the GBR lagoon is from the Wet Tropics, and almost half of the total modelled DIN load is from sugarcane areas. We demonstrate that using locally developed, customised models coupled with a complementary monitoring program can produce reliable estimates of pollutant loads.
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Affiliation(s)
- G L McCloskey
- Department of Resources, Queensland Government, Australia.
| | - R Baheerathan
- Department of Resources, Queensland Government, Australia
| | - C Dougall
- Department of Resources, Queensland Government, Australia
| | - R Ellis
- Department of Environment and Science, Queensland Government, Australia
| | - F R Bennett
- Department of Environment and Science, Queensland Government, Australia
| | - D Waters
- Department of Resources, Queensland Government, Australia
| | - S Darr
- Department of Resources, Queensland Government, Australia
| | - B Fentie
- Department of Environment and Science, Queensland Government, Australia
| | - L R Hateley
- Department of Resources, Queensland Government, Australia
| | - M Askildsen
- Department of Resources, Queensland Government, Australia
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33
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Loiseau C, Thiault L, Devillers R, Claudet J. Cumulative impact assessments highlight the benefits of integrating land-based management with marine spatial planning. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 787:147339. [PMID: 34000542 DOI: 10.1016/j.scitotenv.2021.147339] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 04/19/2021] [Accepted: 04/20/2021] [Indexed: 06/12/2023]
Abstract
Cumulative impact assessments can inform ecosystem-based management by mapping human pressures and assessing their intensity on ecosystem components. However, its use to inform local management is scarce, largely due to the need for fine-grained spatial data representing ecosystem threats that can assess impacts at a local scale. Here, we applied the cumulative impact assessment framework to Moorea's coral reef, French Polynesia to inform the ongoing revision of the island-wide marine spatial management plan. We combined high spatial resolution data on 11 local anthropogenic pressures and four ecological components with expert vulnerability assessments. Results revealed that the entire reef is impacted by at least four pressures: coral reef fisheries, agriculture, land use change and urbanization. These activities together contribute to 87% of the overall cumulative impact. Most importantly, land-based activities contribute to more than half (52%) of the overall impact. Other high-impact activities, such as reef-based tourism, remain very localized and contribute little to the overall human impact. These findings show that by focusing solely on reef-based activities, the current management plan misses critical sources of impact. Not considering land-based activities in the management may lead to decisions that could fail to significantly lower cumulative human impact on the reef. This study demonstrates how operationalizing the cumulative human impact framework at a local scale can help managers identify key leverage points likely to yield improved ecological outcomes.
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Affiliation(s)
- Charles Loiseau
- National Center for Scientific Research, PSL Université Paris, CRIOBE, USR 3278 CNRS-EPHE-UPVD, Maison des Océans, 195 rue Saint-Jacques, 75005 Paris, France; Laboratoire d'Excellence CORAIL, Moorea, French Polynesia.
| | - Lauric Thiault
- National Center for Scientific Research, PSL Université Paris, CRIOBE, USR 3278 CNRS-EPHE-UPVD, Maison des Océans, 195 rue Saint-Jacques, 75005 Paris, France; Laboratoire d'Excellence CORAIL, Moorea, French Polynesia; Moana Ecologic, Rocbaron, France
| | - Rodolphe Devillers
- ESPACE-DEV, Institut de Recherche pour le Développement (IRD), Univ Antilles, Univ Guyane, Univ Montpellier, Univ Réunion, Montpellier, France
| | - Joachim Claudet
- National Center for Scientific Research, PSL Université Paris, CRIOBE, USR 3278 CNRS-EPHE-UPVD, Maison des Océans, 195 rue Saint-Jacques, 75005 Paris, France; Laboratoire d'Excellence CORAIL, Moorea, French Polynesia
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Vaughan EJ, Wynn PM, Wilson SK, Williams GJ, Barker PA, Graham NAJ. Precision and cost-effectiveness of bioindicators to estimate nutrient regimes on coral reefs. MARINE POLLUTION BULLETIN 2021; 170:112606. [PMID: 34153852 DOI: 10.1016/j.marpolbul.2021.112606] [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: 04/30/2020] [Revised: 06/01/2021] [Accepted: 06/04/2021] [Indexed: 06/13/2023]
Abstract
Bioindicators are useful for determining nutrient regimes in marine environments, but their ability to evaluate corals reefs in different ecological states is poorly understood. The precision, availability and congruency of eight potential bioindicators (brown macroalgae, green macroalgae, turf algae, cyanobacteria, soft corals, zoanthids, sponges, and sediment) and their stable isotopic and elemental signatures (δ15N, δ13C, %N, %C, and C:N Ratio) were assessed across 21 reefs in the Inner Seychelles. The coefficient of variation (CoV) for δ15N showed that green and brown macroalgae were highly precise (2.47 ± 0.95, n = 11; 4.68 ± 1.33, n = 16, respectively), though were less common on coral-mortality reefs relative to macroalgal-dominated ones. Zoanthids were also highly precise for δ15N (2.98 ± 1.20), but were more readily available regardless of reef state (n = 18). Congruency was low among these indicators, suggesting that different physiological mechanisms for nutrient processing have a stronger influence on a bioindicator's effectiveness than reef state.
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Affiliation(s)
- Eleanor J Vaughan
- Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK.
| | - Peter M Wynn
- Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK
| | - Shaun K Wilson
- Department of Biodiversity, Conservation and Attractions, Kensington, Perth, Western Australia 6151, Australia; Oceans Institute, University of Western Australia, Crawley, WA 6009, Australia
| | - Gareth J Williams
- School of Ocean Sciences, Bangor University, Menai Bridge, Anglesey LL59 5AB, UK
| | - Philip A Barker
- Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK
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Natural experiments and long-term monitoring are critical to understand and predict marine host-microbe ecology and evolution. PLoS Biol 2021; 19:e3001322. [PMID: 34411089 PMCID: PMC8376202 DOI: 10.1371/journal.pbio.3001322] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Marine multicellular organisms host a diverse collection of bacteria, archaea, microbial eukaryotes, and viruses that form their microbiome. Such host-associated microbes can significantly influence the host’s physiological capacities; however, the identity and functional role(s) of key members of the microbiome (“core microbiome”) in most marine hosts coexisting in natural settings remain obscure. Also unclear is how dynamic interactions between hosts and the immense standing pool of microbial genetic variation will affect marine ecosystems’ capacity to adjust to environmental changes. Here, we argue that significantly advancing our understanding of how host-associated microbes shape marine hosts’ plastic and adaptive responses to environmental change requires (i) recognizing that individual host–microbe systems do not exist in an ecological or evolutionary vacuum and (ii) expanding the field toward long-term, multidisciplinary research on entire communities of hosts and microbes. Natural experiments, such as time-calibrated geological events associated with well-characterized environmental gradients, provide unique ecological and evolutionary contexts to address this challenge. We focus here particularly on mutualistic interactions between hosts and microbes, but note that many of the same lessons and approaches would apply to other types of interactions. This Essay argues that in order to truly understand how marine hosts benefit from the immense diversity of microbes, we need to expand towards long-term, multi-disciplinary research focussing on few areas of the world’s ocean that we refer to as “natural experiments,” where processes can be studied at scales that far exceed those captured in laboratory experiments.
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Cramer KL, Donovan MK, Jackson JBC, Greenstein BJ, Korpanty CA, Cook GM, Pandolfi JM. The transformation of Caribbean coral communities since humans. Ecol Evol 2021; 11:10098-10118. [PMID: 34367562 PMCID: PMC8328467 DOI: 10.1002/ece3.7808] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 05/24/2021] [Accepted: 06/03/2021] [Indexed: 11/06/2022] Open
Abstract
The mass die-off of Caribbean corals has transformed many of this region's reefs to macroalgal-dominated habitats since systematic monitoring began in the 1970s. Although attributed to a combination of local and global human stressors, the lack of long-term data on Caribbean reef coral communities has prevented a clear understanding of the causes and consequences of coral declines. We integrated paleoecological, historical, and modern survey data to track the occurrence of major coral species and life-history groups throughout the Caribbean from the prehuman period to the present. The regional loss of Acropora corals beginning by the 1960s from local human disturbances resulted in increases in the occurrence of formerly subdominant stress-tolerant and weedy scleractinian corals and the competitive hydrozoan Millepora beginning in the 1970s and 1980s. These transformations have resulted in the homogenization of coral communities within individual countries. However, increases in stress-tolerant and weedy corals have slowed or reversed since the 1980s and 1990s in tandem with intensified coral bleaching and disease. These patterns reveal the long history of increasingly stressful environmental conditions on Caribbean reefs that began with widespread local human disturbances and have recently culminated in the combined effects of local and global change.
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Affiliation(s)
- Katie L. Cramer
- Center for Biodiversity Outcomes and School of Life SciencesArizona State UniversityTempeAZUSA
| | - Mary K. Donovan
- Center for Global Discovery and Conservation Science and School of Geographical Sciences and Urban PlanningArizona State UniversityTempeAZUSA
| | - Jeremy B. C. Jackson
- Center for Biodiversity and Conservation and Department of PaleontologyAmerican Museum of Natural HistoryNew YorkNYUSA
| | | | - Chelsea A. Korpanty
- MARUM Center for Marine Environmental SciencesUniversity of BremenBremenGermany
| | - Geoffrey M. Cook
- Department of Biology and Health ScienceNew England CollegeHennikerNHUSA
| | - John M. Pandolfi
- Centre for Marine ScienceSchool of Biological Sciences and ARC Centre of Excellence for Coral Reef StudiesThe University of QueenslandSt LuciaQldAustralia
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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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Devlin MJ, Lyons BP, Johnson JE, Hills JM. The tropical Pacific Oceanscape: Current issues, solutions and future possibilities. MARINE POLLUTION BULLETIN 2021; 166:112181. [PMID: 33676108 DOI: 10.1016/j.marpolbul.2021.112181] [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: 01/28/2021] [Revised: 02/11/2021] [Accepted: 02/11/2021] [Indexed: 06/12/2023]
Abstract
Marine ecosystems across the world's largest ocean - the Pacific Ocean - are being increasingly affected by stressors such as pollution, overfishing, ocean acidification, coastal development and warming events coupled with rising sea levels and increasing frequency of extreme weather. These anthropogenic-driven stressors, which operate cumulatively at varying spatial and temporal scales, are leading to ongoing and pervasive degradation of many marine ecosystems in the Pacific Island region. The effects of global warming and ocean acidification threaten much of the region and impact on the socio-cultural, environmental, economic and human health components of many Pacific Island nations. Simultaneously, resilience to climate change is being reduced as systems are overburdened by other stressors, such as marine and land-based pollution and unsustainable fishing. Consequently, it is important to understand the vulnerability of this region to future environmental scenarios and determine to what extent management actions can help protect, and rebuild ecosystem resilience and maintain ecosystem service provision. This Special Issue of papers explores many of these pressures through case studies across the Pacific Island region, and the impacts of individual and cumulative pressures on the condition, resilience and survival of ecosystems and the communities that depend on them. The papers represent original work from across the tropical Pacific oceanscape, an area that includes 22 Pacific Island countries and territories plus Hawaii and the Philippines. The 39 papers within provide insights on anthropogenic pressures and habitat responses at local, national, and regional scales. The themes range from coastal water quality and human health, assessment of status and trends for marine habitats (e.g. seagrass and coral reefs), and the interaction of local pressures (pollution, overfishing) with increasing temperatures and climate variability. Studies within the Special Issue highlight how local actions, monitoring, tourism values, management, policy and incentives can encourage adaptation to anthropogenic impacts. Conclusions identify possible solutions to support sustainable and harmonious environment and social systems in the unique Pacific Island oceanscape.
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Affiliation(s)
- Michelle J Devlin
- Centre for Environment, Fisheries and Aquaculture Science (Cefas), Lowestoft Laboratory, Pakefield Road, Lowestoft NR330HT, Suffolk, UK; CCSUS, University of East Anglia, Norwich, Norwich, Norfolk, UK; TropWater, James Cook University, Townsville, Queensland, Australia.
| | - Brett P Lyons
- Cefas, Weymouth Laboratory, Barrack Road, Weymouth DT4 8UB, Dorset, UK
| | - Johanna E Johnson
- C2O Pacific, Port Vila, Vanuatu & Cairns, Australia; College of Science & Engineering, James Cook University, Queensland, Australia
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39
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Bergstrom DM, Wienecke BC, van den Hoff J, Hughes L, Lindenmayer DB, Ainsworth TD, Baker CM, Bland L, Bowman DMJS, Brooks ST, Canadell JG, Constable AJ, Dafforn KA, Depledge MH, Dickson CR, Duke NC, Helmstedt KJ, Holz A, Johnson CR, McGeoch MA, Melbourne-Thomas J, Morgain R, Nicholson E, Prober SM, Raymond B, Ritchie EG, Robinson SA, Ruthrof KX, Setterfield SA, Sgrò CM, Stark JS, Travers T, Trebilco R, Ward DFL, Wardle GM, Williams KJ, Zylstra PJ, Shaw JD. Combating ecosystem collapse from the tropics to the Antarctic. GLOBAL CHANGE BIOLOGY 2021; 27:1692-1703. [PMID: 33629799 DOI: 10.1111/gcb.15539] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 01/12/2021] [Accepted: 01/20/2021] [Indexed: 05/05/2023]
Abstract
Globally, collapse of ecosystems-potentially irreversible change to ecosystem structure, composition and function-imperils biodiversity, human health and well-being. We examine the current state and recent trajectories of 19 ecosystems, spanning 58° of latitude across 7.7 M km2 , from Australia's coral reefs to terrestrial Antarctica. Pressures from global climate change and regional human impacts, occurring as chronic 'presses' and/or acute 'pulses', drive ecosystem collapse. Ecosystem responses to 5-17 pressures were categorised as four collapse profiles-abrupt, smooth, stepped and fluctuating. The manifestation of widespread ecosystem collapse is a stark warning of the necessity to take action. We present a three-step assessment and management framework (3As Pathway Awareness, Anticipation and Action) to aid strategic and effective mitigation to alleviate further degradation to help secure our future.
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Affiliation(s)
- Dana M Bergstrom
- Australian Antarctic Division, Department of Agriculture, Water and the Environment, Kingston, Tas., Australia
- Global Challenges Program, University of Wollongong, Wollongong, NSW, Australia
| | - Barbara C Wienecke
- Australian Antarctic Division, Department of Agriculture, Water and the Environment, Kingston, Tas., Australia
| | - John van den Hoff
- Australian Antarctic Division, Department of Agriculture, Water and the Environment, Kingston, Tas., Australia
| | | | - David B Lindenmayer
- Fenner School of Environment and Society, Australian National University, Canberra, ACT, Australia
| | - Tracy D Ainsworth
- School of Biological, Earth and Environmental Sciences, The University of New South Wales, Randwick, NSW, Australia
| | - Christopher M Baker
- School of Mathematics and Statistics, The University of Melbourne, Parkville, Vic., Australia
- Melbourne Centre for Data Science, The University of Melbourne, Parkville, Vic., Australia
- Centre of Excellence for Biosecurity Risk Analysis, The University of Melbourne, Parkville, Vic., Australia
| | - Lucie Bland
- Eureka Publishing, Thornbury, Vic., Australia
| | - David M J S Bowman
- School of Natural Sciences, University of Tasmania, Hobart, Tas., Australia
| | - Shaun T Brooks
- Institute for Marine and Antarctic Studies, University of Tasmania, Battery Point, Tas., Australia
| | - Josep G Canadell
- Climate Science Centre, Commonwealth Scientific and Industrial Research Organisation, Black Mountain, ACT, Australia
| | - Andrew J Constable
- Centre for Marine Socioecology, University of Tasmania, Battery Point, Tas., Australia
| | | | - Michael H Depledge
- European Centre for Environment and Human Health, University of Exeter Medical School, Truro, UK
| | | | - Norman C Duke
- Centre for Tropical Water and Aquatic Ecosystem Research, James Cook University, Townsville, Qld, Australia
| | - Kate J Helmstedt
- School of Mathematical Sciences, Queensland University of Technology, Brisbane, Qld, Australia
| | - Andrés Holz
- Department of Geography, Portland State University, Portland, OR, USA
| | - Craig R Johnson
- Institute for Marine and Antarctic Studies, University of Tasmania, Battery Point, Tas., Australia
| | - Melodie A McGeoch
- School of Biological Sciences, Monash University, Clayton, Vic., Australia
| | - Jessica Melbourne-Thomas
- Centre for Marine Socioecology, University of Tasmania, Battery Point, Tas., Australia
- Commonwealth Scientific and Industrial Research Organisation, Oceans and Atmosphere, Battery Point, Tas., Australia
| | - Rachel Morgain
- Fenner School of Environment and Society, Australian National University, Canberra, ACT, Australia
| | - Emily Nicholson
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Burwood, Vic., Australia
| | - Suzanne M Prober
- Commonwealth Scientific and Industrial Research Organisation, Land and Water, Wembley, WA, Australia
| | - Ben Raymond
- Australian Antarctic Division, Department of Agriculture, Water and the Environment, Kingston, Tas., Australia
- Institute for Marine and Antarctic Studies, University of Tasmania, Battery Point, Tas., Australia
| | - Euan G Ritchie
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Burwood, Vic., Australia
| | - Sharon A Robinson
- Global Challenges Program, University of Wollongong, Wollongong, NSW, Australia
- Centre for Sustainable Ecosystem Solutions, University of Wollongong, Wollongong, NSW, Australia
| | - Katinka X Ruthrof
- Department of Biodiversity, Conservation and Attractions, Kensington, WA, Australia
- Environmental and Conservation Sciences, Murdoch University, Murdoch, WA, Australia
| | | | - Carla M Sgrò
- School of Biological Sciences, Monash University, Clayton, Vic., Australia
| | - Jonathan S Stark
- Australian Antarctic Division, Department of Agriculture, Water and the Environment, Kingston, Tas., Australia
| | - Toby Travers
- Institute for Marine and Antarctic Studies, University of Tasmania, Battery Point, Tas., Australia
| | - Rowan Trebilco
- Centre for Marine Socioecology, University of Tasmania, Battery Point, Tas., Australia
- Commonwealth Scientific and Industrial Research Organisation, Oceans and Atmosphere, Battery Point, Tas., Australia
| | - Delphi F L Ward
- Institute for Marine and Antarctic Studies, University of Tasmania, Battery Point, Tas., Australia
| | - Glenda M Wardle
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, Australia
| | - Kristen J Williams
- Commonwealth Scientific and Industrial Research Organisation, Canberra, ACT, Australia
| | - Phillip J Zylstra
- Centre for Sustainable Ecosystem Solutions, University of Wollongong, Wollongong, NSW, Australia
- School of Molecular and Life Sciences, Curtin University, Bentley, WA, Australia
| | - Justine D Shaw
- School of Biological Sciences, The University of Queensland, St Lucia, Qld, Australia
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Condie SA, Anthony KRN, Babcock RC, Baird ME, Beeden R, Fletcher CS, Gorton R, Harrison D, Hobday AJ, Plagányi ÉE, Westcott DA. Large-scale interventions may delay decline of the Great Barrier Reef. ROYAL SOCIETY OPEN SCIENCE 2021; 8:201296. [PMID: 34007456 PMCID: PMC8080001 DOI: 10.1098/rsos.201296] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 03/31/2021] [Indexed: 05/31/2023]
Abstract
On the iconic Great Barrier Reef (GBR), the cumulative impacts of tropical cyclones, marine heatwaves and regular outbreaks of coral-eating crown-of-thorns starfish (CoTS) have severely depleted coral cover. Climate change will further exacerbate this situation over the coming decades unless effective interventions are implemented. Evaluating the efficacy of alternative interventions in a complex system experiencing major cumulative impacts can only be achieved through a systems modelling approach. We have evaluated combinations of interventions using a coral reef meta-community model. The model consisted of a dynamic network of 3753 reefs supporting communities of corals and CoTS connected through ocean larval dispersal, and exposed to changing regimes of tropical cyclones, flood plumes, marine heatwaves and ocean acidification. Interventions included reducing flood plume impacts, expanding control of CoTS populations, stabilizing coral rubble, managing solar radiation and introducing heat-tolerant coral strains. Without intervention, all climate scenarios resulted in precipitous declines in GBR coral cover over the next 50 years. The most effective strategies in delaying decline were combinations that protected coral from both predation (CoTS control) and thermal stress (solar radiation management) deployed at large scale. Successful implementation could expand opportunities for climate action, natural adaptation and socioeconomic adjustment by at least one to two decades.
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Affiliation(s)
- Scott A. Condie
- CSIRO Oceans and Atmosphere, Hobart, Tasmania, Australia
- Centre for Marine Socioecology, University of Tasmania, Hobart, Tasmania, Australia
| | - Kenneth R. N. Anthony
- Australian Institute of Marine Science, Townsville, Queensland, Australia
- School of Biological Sciences, The University of Queensland, Brisbane, Queensland, Australia
| | - Russ C. Babcock
- CSIRO Oceans and Atmosphere, Brisbane, Queensland, Australia
| | - Mark E. Baird
- CSIRO Oceans and Atmosphere, Hobart, Tasmania, Australia
| | - Roger Beeden
- Great Barrier Reef Marine Park Authority, Townsville, Queensland, Australia
| | | | - Rebecca Gorton
- CSIRO Oceans and Atmosphere, Hobart, Tasmania, Australia
| | - Daniel Harrison
- National Marine Science Centre, Southern Cross University, Coffs Harbour, New South Wales, Australia
- Marine Studies Centre, School of Geosciences, University of Sydney, Camperdown, New South Wales, Australia
| | - Alistair J. Hobday
- CSIRO Oceans and Atmosphere, Hobart, Tasmania, Australia
- Centre for Marine Socioecology, University of Tasmania, Hobart, Tasmania, Australia
| | - Éva E. Plagányi
- Centre for Marine Socioecology, University of Tasmania, Hobart, Tasmania, Australia
- CSIRO Oceans and Atmosphere, Brisbane, Queensland, Australia
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Hall MO, Bell SS, Furman BT, Durako MJ. Natural recovery of a marine foundation species emerges decades after landscape-scale mortality. Sci Rep 2021; 11:6973. [PMID: 33772042 PMCID: PMC7997892 DOI: 10.1038/s41598-021-86160-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 03/04/2021] [Indexed: 11/27/2022] Open
Abstract
Globally, the conditions and time scales underlying coastal ecosystem recovery following disturbance remain poorly understood, and post-disturbance examples of resilience based on long-term studies are particularly rare. Here, we documented the recovery of a marine foundation species (turtlegrass) following a hypersalinity-associated die-off in Florida Bay, USA, one of the most spatially extensive mortality events for seagrass ecosystems on record. Based upon annual sampling over two decades, foundation species recovery across the landscape was demonstrated by two ecosystem responses: the range of turtlegrass biomass met or exceeded levels present prior to the die-off, and turtlegrass regained dominance of seagrass community structure. Unlike reports for most marine taxa, recovery followed without human intervention or reduction to anthropogenic impacts. Our long-term study revealed previously uncharted resilience in subtropical seagrass landscapes but warns that future persistence of the foundation species in this iconic ecosystem will depend upon the frequency and severity of drought-associated perturbation.
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Affiliation(s)
- Margaret O Hall
- Florida Fish and Wildlife Conservation Commission, Florida Fish and Wildlife Research Institute, St. Petersburg, FL, 33701, USA
| | - Susan S Bell
- Department of Integrative Biology, University of South Florida, Tampa, FL, 33620, USA.
| | - Bradley T Furman
- Florida Fish and Wildlife Conservation Commission, Florida Fish and Wildlife Research Institute, St. Petersburg, FL, 33701, USA
| | - Michael J Durako
- Center for Marine Science, University of North Carolina at Wilmington, Wilmington, NC, 28403, USA
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42
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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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43
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Recent Advancement of the Sensors for Monitoring the Water Quality Parameters in Smart Fisheries Farming. COMPUTERS 2021. [DOI: 10.3390/computers10030026] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Water quality is the most critical factor affecting fish health and performance in aquaculture production systems. Fish life is mostly dependent on the water fishes live in for all their needs. Therefore, it is essential to have a clear understanding of the water quality requirements of the fish. This research discusses the critical water parameters (temperature, pH, nitrate, phosphate, calcium, magnesium, and dissolved oxygen (DO)) for fisheries and reviews the existing sensors to detect those parameters. Moreover, this paper proposes a prospective solution for smart fisheries that will help to monitor water quality factors, make decisions based on the collected data, and adapt more quickly to changing conditions.
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44
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Graves CA, Powell A, Stone M, Redfern F, Biko T, Devlin M. Marine water quality of a densely populated Pacific atoll (Tarawa, Kiribati): Cumulative pressures and resulting impacts on ecosystem and human health. MARINE POLLUTION BULLETIN 2021; 163:111951. [PMID: 33472138 DOI: 10.1016/j.marpolbul.2020.111951] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 12/14/2020] [Accepted: 12/16/2020] [Indexed: 06/12/2023]
Abstract
The resilience of coastal ecosystems and communities to poor environmental and health outcomes is threatened by cumulative anthropogenic pressures. In Kiribati, a developing Pacific Island country where human activities are closely connected with the ocean, both people and environment are particularly vulnerable to coastal pollution. We present a survey of environmental and human health water quality parameters around urban South Tarawa, and an overview of their impacts on the semi-enclosed atoll. Tarawa has significant water quality issues and decisions to guide improvements are hindered by a persistent lack of appropriate and sufficient observations. Our snapshot assessment identifies highest risk locations related to chronic focused and diffuse pollution inputs, and where mixing and dilution with ocean water is restricted. We demonstrate the importance of monitoring in the context of rapidly changing pressures. Our recommendations are relevant to other atoll ecosystems where land-based activities and ocean health are tightly interlinked.
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Affiliation(s)
- Carolyn A Graves
- Centre for Environment, Fisheries and Aquaculture Science, Pakefield Road, Lowestoft, Suffolk NR33 0HT, UK; Centre for Environment, Fisheries and Aquaculture Science, The Nothe, Barrack Road, Weymouth, Dorset DT4 8UB, UK; Marine Collaborative Centre for Sustainable Use of the Seas (CCSUS), School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ, UK.
| | - Andy Powell
- Centre for Environment, Fisheries and Aquaculture Science, The Nothe, Barrack Road, Weymouth, Dorset DT4 8UB, UK.
| | - Michelle Stone
- Centre for Environment, Fisheries and Aquaculture Science, The Nothe, Barrack Road, Weymouth, Dorset DT4 8UB, UK.
| | - Farran Redfern
- Environment and Conservation Division, Ministry of Environment Lands and Agriculture Developments, Bikenibeu, Tarawa, Kiribati.
| | - Teema Biko
- Environment and Conservation Division, Ministry of Environment Lands and Agriculture Developments, Bikenibeu, Tarawa, Kiribati.
| | - Michelle Devlin
- Centre for Environment, Fisheries and Aquaculture Science, The Nothe, Barrack Road, Weymouth, Dorset DT4 8UB, UK; Marine Collaborative Centre for Sustainable Use of the Seas (CCSUS), School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ, UK.
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45
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Adam TC, Burkepile DE, Holbrook SJ, Carpenter RC, Claudet J, Loiseau C, Thiault L, Brooks AJ, Washburn L, Schmitt RJ. Landscape-scale patterns of nutrient enrichment in a coral reef ecosystem: implications for coral to algae phase shifts. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2021; 31:e2227. [PMID: 32918509 DOI: 10.1002/eap.2227] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 05/01/2020] [Accepted: 06/15/2020] [Indexed: 06/11/2023]
Abstract
Nutrient pollution is altering coastal ecosystems worldwide. On coral reefs, excess nutrients can favor the production of algae at the expense of reef-building corals, yet the role of nutrients in driving community changes such as shifts from coral to macroalgae is not well understood. Here we investigate the potential role of anthropogenic nutrient loading in driving recent coral-to-macroalgae phase shifts on reefs in the lagoons surrounding the Pacific island of Moorea, French Polynesia. We use nitrogen (N) tissue content and stable isotopes (δ15 N) in an abundant macroalga (Turbinaria ornata) together with empirical models of nutrient discharge to describe spatial and temporal patterns of nutrient enrichment in the lagoons. We then employ time series data to test whether recent increases in macroalgae are associated with nutrients. Our results revealed that patterns of N enrichment were linked to several factors, including rainfall, wave-driven circulation, and distance from anthropogenic nutrient sources, especially human sewage. Reefs near large watersheds, where inputs of N from sewage and agriculture are high, have been consistently enriched in N for at least the last decade. In many of these areas, corals have decreased and macroalgae have increased, while reefs with lower levels of N input have maintained high cover of coral and low cover of macroalgae. Importantly, these patchy phase shifts to macroalgae have occurred despite substantial island-wide increases in the density and biomass of herbivorous fishes over the time period. Together, these results indicate that nutrient loading may be an important driver of coral-to-macroalgae phase shifts in the lagoons of Moorea even though the reefs harbor an abundant and diverse herbivore assemblage. These results emphasize the important role that bottom-up factors can play in driving coral-to-macroalgae phase shifts and underscore the critical importance of watershed management for reducing inputs of nutrients and other land-based pollutants to coral reef ecosystems.
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Affiliation(s)
- Thomas C Adam
- Marine Science Institute, University of California, Santa Barbara, California, 93106, USA
| | - Deron E Burkepile
- Marine Science Institute, University of California, Santa Barbara, California, 93106, USA
- Department of Ecology, Evolution, and Marine Biology, University of California, Santa Barbara, California, 93106, USA
| | - Sally J Holbrook
- Marine Science Institute, University of California, Santa Barbara, California, 93106, USA
- Department of Ecology, Evolution, and Marine Biology, University of California, Santa Barbara, California, 93106, USA
| | - Robert C Carpenter
- Department of Biology, California State University Northridge, Northridge, California, 91330, USA
| | - Joachim Claudet
- National Center for Scientific Research, PSL Université Paris, CRIOBE, USR 3278 CNRS-EPHE-UPVD, Maison des Océans, 195 rue Saint-Jacques, Paris, 75005, France
- Laboratoire d'Excellence CORAIL, Moorea, French Polynesia
| | - Charles Loiseau
- National Center for Scientific Research, PSL Université Paris, CRIOBE, USR 3278 CNRS-EPHE-UPVD, Maison des Océans, 195 rue Saint-Jacques, Paris, 75005, France
- Laboratoire d'Excellence CORAIL, Moorea, French Polynesia
| | - Lauric Thiault
- National Center for Scientific Research, PSL Université Paris, CRIOBE, USR 3278 CNRS-EPHE-UPVD, Maison des Océans, 195 rue Saint-Jacques, Paris, 75005, France
- Laboratoire d'Excellence CORAIL, Moorea, French Polynesia
| | - Andrew J Brooks
- Marine Science Institute, University of California, Santa Barbara, California, 93106, USA
| | - Libe Washburn
- Marine Science Institute, University of California, Santa Barbara, California, 93106, USA
- Department of Geography, University of California, Santa Barbara, California, 93106, USA
| | - Russell J Schmitt
- Marine Science Institute, University of California, Santa Barbara, California, 93106, USA
- Department of Ecology, Evolution, and Marine Biology, University of California, Santa Barbara, California, 93106, USA
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46
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Wakwella A, Mumby PJ, Roff G. Sedimentation and overfishing drive changes in early succession and coral recruitment. Proc Biol Sci 2020; 287:20202575. [PMID: 33323081 DOI: 10.1098/rspb.2020.2575] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Sedimentation and overfishing are important local stressors on coral reefs that can independently result in declines in coral recruitment and shifts to algal-dominated states. However, the role of herbivory in driving recovery across environmental gradients is often unclear. Here we investigate early successional benthic communities and coral recruitment across a sediment gradient in Palau, Micronesia over a 12-month period. Total sedimentation rates measured by 'TurfPods' varied from 0.03 ± 0.1 SE mg cm-2 d-1 at offshore sites to 1.32 ± 0.2 mg cm-2 d-1 at inshore sites. To assess benthic succession, three-dimensional settlement tiles were deployed at sites with experimental cages used to exclude tile access to larger herbivorous fish. Benthic assemblages exhibited rapid transitions across the sediment gradient within three months of deployment. At low levels of sedimentation (less than 0.6 mg cm-2 d-1), herbivory resulted in communities dominated by coral recruitment inducers (short turf algae and crustose coralline algae), whereas exclusion of herbivores resulted in the overgrowth of coral inhibitors (encrusting and upright foliose macroalgae). An 'inducer threshold' was found under increasing levels of sedimentation (greater than 0.6 mg cm-2 d-1), with coral inducers having limited to no presence in communities, and herbivore access to tiles resulted in sediment-laden turf algal assemblages, while exclusion of herbivores resulted in invertebrates (sponges, ascidians) and terrestrial sediment accumulation. A 'coral recruitment threshold' was found at 0.8 mg cm-2 d-1, below which net coral recruitment was reduced by 50% in the absence of herbivores, while recruitment was minimal above the threshold. Our results highlight nonlinear trajectories of benthic succession across sediment gradients and identify strong interactions between sediment and herbivory that have cascading effects on coral recruitment. Local management strategies that aim to reduce sedimentation and turbidity and manage herbivore fisheries can have measurable effects on benthic community succession and coral recruitment, enhancing reef resilience and driving coral recovery.
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Affiliation(s)
- Ama Wakwella
- Marine Spatial Ecology Lab, School of Biological Sciences, University of Queensland, St Lucia, Queensland 4072, Australia
| | - Peter J Mumby
- Marine Spatial Ecology Lab, School of Biological Sciences, University of Queensland, St Lucia, Queensland 4072, Australia.,Palau International Coral Reef Center, Koror, Palau
| | - George Roff
- Marine Spatial Ecology Lab, School of Biological Sciences, University of Queensland, St Lucia, Queensland 4072, Australia
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47
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Foo SA, Asner GP. Impacts of remotely sensed environmental drivers on coral outplant survival. Restor Ecol 2020. [DOI: 10.1111/rec.13309] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Shawna A. Foo
- Center for Global Discovery and Conservation Science Arizona State University Tempe, Arizona 85287 U.S.A
| | - Gregory P. Asner
- Center for Global Discovery and Conservation Science Arizona State University Tempe, Arizona 85287 U.S.A
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48
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Ling SD, Cowan ZL, Boada J, Flukes EB, Pratchett MS. Homing behaviour by destructive crown-of-thorns starfish is triggered by local availability of coral prey. Proc Biol Sci 2020; 287:20201341. [PMID: 33143585 DOI: 10.1098/rspb.2020.1341] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Corallivorous crown-of-thorns starfishes (Acanthaster spp.) can decimate coral assemblages on Indo-Pacific coral reefs during population outbreaks. While initial drivers of population irruptions leading to outbreaks remain largely unknown, subsequent dispersal of outbreaks appears coincident with depletion of coral prey. Here, we used in situ time-lapse photography to characterize movement of the Pacific crown-of-thorns starfish (Acanthaster cf. solaris) in the northern and southern Great Barrier Reef in 2015, during the fourth recorded population outbreak of the starfish, but prior to widespread coral bleaching. Daily tracking of 58 individuals over a total of 1117 h revealed all starfish to move a minimum of 0.52 m, with around half of all tracked starfish showing negligible daily displacement (less than 1 m day-1), ranging up to a maximum of 19 m day-1. Movement was primarily nocturnal and daily displacement varied spatially with variation in local availability of Acropora spp., which is the preferred coral prey. Two distinct behavioural modes emerged: (i) homing movement, whereby tracked paths (as tested against a random-walk-model) involved short displacement distances following distinct 'outward' movement to Acropora prey (typically displaying 'feeding scars') and 'homebound' movement to nearby shelter; versus (ii) roaming movement, whereby individuals showed directional movement beyond initial tracking positions without return. Logistic modelling revealed more than half of all tracked starfish demonstrated homing when local abundance (percentage cover) of preferred Acropora coral prey was greater than 33%. Our results reveal facultative homing by Acanthaster with the prey-dependent behavioural switch to roaming forays providing a mechanism explaining localized aggregations and diffusion of these population irruptions as prey is locally depleted.
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Affiliation(s)
- S D Ling
- Institute for Marine and Antarctic Studies, University of Tasmania, 20 Castray Esplanade, Battery Point, Tasmania 7004, Australia
| | - Z-L Cowan
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Queensland 4811, Australia.,Department of Zoology, University of Cambridge, Downing St, Cambridge, UK
| | - J Boada
- Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals, Universitat de Barcelona, Barcelona, Spain.,Centre d'Estudis Avançats de Blanes, Carrer d'Accés a la cala Sant Francesc, Blanes, Spain
| | - E B Flukes
- Institute for Marine and Antarctic Studies, University of Tasmania, 20 Castray Esplanade, Battery Point, Tasmania 7004, Australia
| | - M S Pratchett
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Queensland 4811, Australia
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Marques JA, Flores F, Patel F, Bianchini A, Uthicke S, Negri AP. Acclimation history modulates effect size of calcareous algae (Halimeda opuntia) to herbicide exposure under future climate scenarios. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 739:140308. [PMID: 32846507 DOI: 10.1016/j.scitotenv.2020.140308] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 06/11/2020] [Accepted: 06/15/2020] [Indexed: 06/11/2023]
Abstract
Tropical marine habitat-builders such as calcifying green algae can be susceptible to climate change (warming and acidification). This study evaluated the cumulative effects of ocean warming (OW), ocean acidification (OA) and the herbicide diuron on the calcifying green algae Halimeda opuntia. We also assessed the influence of acclimation history to experimental climate change conditions on physiological responses. H. opuntia were exposed for 15 days to orthogonal combinations of three climate scenarios [ambient (28 °C, pCO2 = 378 ppm), 2050 (29 °C, pCO2 = 567 ppm) and 2100 (30 °C, pCO2 = 721 ppm)] and to six diuron concentrations (up to 29 μg L-1). Half of the H. opuntia had been acclimated for eight months to the climate scenarios in a mesocosm approach, while the remaining half were not pre-acclimated, as is current practice in most experiments. Climate effects on quantum yield (ΔF/Fm'), photosynthesis and calcification in future climate scenarios were significantly stronger (by -24, -46 and +26%, respectively) in non-acclimated algae, suggesting experimental bias may exaggerate effects in organisms not appropriately acclimated to future-climate conditions. Thus, full analysis was done on acclimated plants only. Interactive effects of future climate scenarios and diuron were observed for ΔF/Fm', while the detrimental effects of climate and diuron on net photosynthesis and total antioxidant capacity (TAC) were additive. Calcification-related enzymes were negatively affected only by diuron, with inhibition of Ca-ATPase and upregulation of carbonic anhydrase. The combined and consistent physiological and biochemical evidence of negative impacts (across six indicators) of both herbicide and future-climate conditions on the health of H. opuntia highlights the need to address both climate change and water quality. Guideline values for contaminants may also need to be lowered considering 'climate adjusted thresholds'. Importantly, this study highlights the value of applying substantial future climate acclimation periods in experimental studies to avoid exaggerated organism responses to OW and OA.
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Affiliation(s)
- Joseane A Marques
- Programa de Pós-Graduação em Oceanografia Biológica, Universidade Federal do Rio Grande, RS, Brazil.
| | - Florita Flores
- Australian Institute of Marine Science, Townsville, QLD 4810, Australia.
| | - Frances Patel
- Australian Institute of Marine Science, Townsville, QLD 4810, Australia.
| | - Adalto Bianchini
- Instituto de Ciências Biológicas, Universidade Federal do Rio Grande, RS, Brazil.
| | - Sven Uthicke
- Australian Institute of Marine Science, Townsville, QLD 4810, Australia.
| | - Andrew P Negri
- Australian Institute of Marine Science, Townsville, QLD 4810, Australia.
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50
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Matthews SA, Mellin C, Pratchett MS. Larval connectivity and water quality explain spatial distribution of crown-of-thorns starfish outbreaks across the Great Barrier Reef. ADVANCES IN MARINE BIOLOGY 2020; 87:223-258. [PMID: 33293012 DOI: 10.1016/bs.amb.2020.08.007] [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] [Indexed: 06/12/2023]
Abstract
Outbreaks of the coral eating crown-of-thorns starfish (COTS; Acanthasts cf. solaris) occur in cyclical waves along the Great Barrier Reef (GBR), contributing significantly to the decline in hard coral cover over the past 30 years. One main difficulty faced by scientists and managers alike, is understanding the relative importance of contributing factors to COTS outbreaks such as increased nutrients and water quality, larval connectivity, fishing pressure, and abiotic conditions. We analysed COTS abundances from the most recent outbreak (2010-2018) using both boosted regression trees and generalised additive models to identify key predictors of COTS outbreaks. We used this approach to predict the suitability of each reef on the GBR for COTS outbreaks at three different levels: (1) reefs with COTS present intermittently (Presence); (2) reefs with COTS widespread and present in most samples and (Prevalence) (3) reefs experiencing outbreak levels of COTS (Outbreak). We also compared the utility of two auto-covariates accounting for spatial autocorrelation among observations, built using weighted inverse distance and weighted larval connectivity to reefs supporting COTS populations, respectively. Boosted regression trees (BRT) and generalised additive mixed models (GAMM) were combined in an ensemble model to reduce the effect of model uncertainty on predictions of COTS presence, prevalence and outbreaks. Our results from best performing models indicate that temperature (Degree Heating Week exposure: relative importance=13.1%) and flood plume exposure (13.0%) are the best predictors of COTS presence, variability in chlorophyll concentration (12.6%) and flood plume exposure (8.2%) best predicted COTS prevalence and larval connectivity potential (22.7%) and minimum sea surface temperature (8.0%) are the best predictors of COTS outbreaks. Whether the reef was open or closed to fishing, however, had no significant effect on either COTS presence, prevalence or outbreaks in BRT results (<0.5%). We identified major hotspots of COTS activity primarily on the mid shelf central GBR and on the southern Swains reefs. This study provides the first empirical comparison of the major hypotheses of COTS outbreaks and the first validated predictions of COTS outbreak potential at the GBR scale incorporating connectivity, nutrients, biophysical and spatial variables, providing a useful aid to management of this pest species on the GBR.
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Affiliation(s)
- S A Matthews
- Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD, Australia; Australian Institute of Marine Science, Townsville, QLD, Australia.
| | - C Mellin
- The Environment Institute and School of Biological Sciences, University of Adelaide, Adelaide, SA, Australia
| | - Morgan S Pratchett
- Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD, Australia
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