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Talbot E, Jontila JBS, Gonzales BJ, Dolorosa RG, Jose ED, Sajorne R, Sailley S, Kay S, Queirós AM. Incorporating climate-readiness into fisheries management strategies. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 918:170684. [PMID: 38320704 DOI: 10.1016/j.scitotenv.2024.170684] [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: 08/04/2023] [Revised: 01/15/2024] [Accepted: 02/02/2024] [Indexed: 02/10/2024]
Abstract
Tropical oceans are among the first places to exhibit climate change signals, affecting the habitat distribution and abundance of marine fish. These changes to stocks, and subsequent impacts on fisheries production, may have considerable implications for coastal communities dependent on fisheries for food security and livelihoods. Understanding the impacts of climate change on tropical marine fisheries is therefore an important step towards developing sustainable, climate-ready fisheries management measures. We apply an established method of spatial meta-analysis to assess species distribution modelling datasets for key species targeted by the Philippines capture fisheries. We analysed datasets under two global emissions scenarios (RCP4.5 and RCP8.5) and varying degrees of fishing pressure to quantify potential climate vulnerability of the target community. We found widespread responses to climate change in pelagic species in particular, with abundances projected to decline across much of the case study area, highlighting the challenges of maintaining food security in the face of a rapidly changing climate. We argue that sustainable fisheries management in the Philippines in the face of climate change can only be achieved through management strategies that allow for the mitigation of, and adaptation to, pressures already locked into the climate system for the near term. Our analysis may support this, providing fisheries managers with the means to identify potential climate change hotspots, bright spots and refugia, thereby supporting the development of climate-ready management plans.
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Affiliation(s)
- Elizabeth Talbot
- Plymouth Marine Laboratory, Prospect Place, Plymouth PL1 3DH, United Kingdom.
| | - Jean-Beth S Jontila
- College of Fisheries and Aquatic Sciences, Western Philippines University, Puerto Princesa City, Philippines
| | - Benjamin J Gonzales
- College of Fisheries and Aquatic Sciences, Western Philippines University, Puerto Princesa City, Philippines
| | - Roger G Dolorosa
- College of Fisheries and Aquatic Sciences, Western Philippines University, Puerto Princesa City, Philippines
| | - Edgar D Jose
- College of Arts and Sciences, North Eastern Mindanao State University, Lianga, Surigao Del Sur, Philippines
| | - Recca Sajorne
- College of Fisheries and Aquatic Sciences, Western Philippines University, Puerto Princesa City, Philippines
| | - Sevrine Sailley
- Plymouth Marine Laboratory, Prospect Place, Plymouth PL1 3DH, United Kingdom
| | - Susan Kay
- Plymouth Marine Laboratory, Prospect Place, Plymouth PL1 3DH, United Kingdom
| | - Ana M Queirós
- Plymouth Marine Laboratory, Prospect Place, Plymouth PL1 3DH, United Kingdom
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2
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Caughman AM, Gaines SD, Bradley D. Climate change reduces long-term population benefits from no-take marine protected areas through selective pressures on species movement. GLOBAL CHANGE BIOLOGY 2024; 30:e17240. [PMID: 38511480 DOI: 10.1111/gcb.17240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 02/23/2024] [Accepted: 03/02/2024] [Indexed: 03/22/2024]
Abstract
Marine protected areas (MPAs) are important conservation tools that confer ecosystem benefits by removing fishing within their borders to allow stocks to rebuild. Fishing mortality outside a traditionally fixed MPA can exert selective pressure for low movement alleles, resulting in enhanced protection. While evolving to move less may be useful for conservation presently, it could be detrimental in the face of climate change for species that need to move to track their thermal optimum. Here, we build a spatially explicit simulation model to assess the impact of movement evolution in and around static MPAs resulting from both fishing mortality and temperature-dependent natural mortality on conservation benefits across five climate scenarios: (i) linear mean temperature shift, (ii) El Niño/La Niña conditions, (iii) heat waves, (iv) heatwaves with a mean temperature shift, and (v) no climate change. While movement evolution allows populations within MPAs to survive longer, we find that over time, climate change degrades the benefits by selecting for higher movement genotypes. Resulting population declines within MPAs are faster than expected based on climate mortality alone, even within the largest MPAs. Our findings suggest that while static MPAs may conserve species for a time, other strategies, such as dynamic MPA networks or assisted migration, may also be required to effectively incorporate climate change into conservation planning.
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Affiliation(s)
- Alicia M Caughman
- Bren School of Environmental Science and Management, University of California, Santa Barbara, Santa Barbara, California, USA
| | - Steven D Gaines
- Bren School of Environmental Science and Management, University of California, Santa Barbara, Santa Barbara, California, USA
| | - Darcy Bradley
- Bren School of Environmental Science and Management, University of California, Santa Barbara, Santa Barbara, California, USA
- Marine Science Institute, University of California, Santa Barbara, Santa Barbara, California, USA
- The Nature Conservancy, California Oceans Program, Santa Barbara, California, USA
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3
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Sanchez L, Loiseau N, Edgar GJ, Hautecoeur C, Leprieur F, Manel S, McLean M, Stuart-Smith RD, Velez L, Mouillot D. Rarity mediates species-specific responses of tropical reef fishes to protection. Ecol Lett 2024; 27:e14418. [PMID: 38532624 DOI: 10.1111/ele.14418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 02/26/2024] [Accepted: 02/28/2024] [Indexed: 03/28/2024]
Abstract
Marine protected areas (MPAs) are the most widely applied tool for marine biodiversity conservation, yet many gaps remain in our understanding of their species-specific effects, partly because the socio-environmental context and spatial autocorrelation may blur and bias perceived conservation outcomes. Based on a large data set of nearly 3000 marine fish surveys spanning all tropical regions of the world, we build spatially explicit models for 658 fish species to estimate species-specific responses to protection while controlling for the environmental, habitat and socio-economic contexts experienced across their geographic ranges. We show that the species responses are highly variable, with ~40% of fishes not benefitting from protection. When investigating how traits influence species' responses, we find that rare top-predators and small herbivores benefit the most from MPAs while mid-trophic level species benefit to a lesser extent, and rare large herbivores experience adverse effects, indicating potential trophic cascades.
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Affiliation(s)
- Loïc Sanchez
- MARBEC, Univ Montpellier, CNRS, IFREMER, IRD, Montpellier, France
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, Montpellier, France
| | - Nicolas Loiseau
- MARBEC, Univ Montpellier, CNRS, IFREMER, IRD, Montpellier, France
| | - Graham J Edgar
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia
| | - Cyril Hautecoeur
- MARBEC, Univ Montpellier, CNRS, IFREMER, IRD, Montpellier, France
| | - Fabien Leprieur
- MARBEC, Univ Montpellier, CNRS, IFREMER, IRD, Montpellier, France
- Institut Universitaire de France, Paris, France
| | - Stéphanie Manel
- Institut Universitaire de France, Paris, France
- CEFE, Univ Montpellier, CNRS, EPHE-PSL University, IRD, Montpellier, France
| | - Matthew McLean
- Department of Biology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Rick D Stuart-Smith
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia
| | - Laure Velez
- MARBEC, Univ Montpellier, CNRS, IFREMER, IRD, Montpellier, France
| | - David Mouillot
- MARBEC, Univ Montpellier, CNRS, IFREMER, IRD, Montpellier, France
- Institut Universitaire de France, Paris, France
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Mumby PJ, Steneck RS, Roff G, Paul VJ. Marine reserves, fisheries ban, and 20 years of positive change in a coral reef ecosystem. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2021; 35:1473-1483. [PMID: 33909928 DOI: 10.1111/cobi.13738] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 12/31/2020] [Accepted: 01/19/2021] [Indexed: 06/12/2023]
Abstract
By 2004, Belize was exhibiting classic fishing down of the food web. Groupers (Serranidae) and snappers (Lutjanidae) were scarce and fisheries turned to parrotfishes (Scarinae), leading to a 41% decline in their biomass. Several policies were enacted in 2009-2010, including a moratorium on fishing parrotfish and a new marine park with no-take areas. Using a 20-year time series on reef fish and benthos, we evaluated the impact of these policies approximately 10 years after their implementation. Establishment of the Southwater Caye Marine Reserve led to a recovery of snapper at 2 out of 3 sites, but there was no evidence of recovery outside the reserve. Snapper populations in an older reserve continued to increase, implying that at least 9 years is required for their recovery. Despite concerns over the feasibility of banning parrotfish harvest once it has become a dominant fin fishery, parrotfishes returned and exceeded biomass levels prior to the fishery. The majority of these changes involved an increase in parrotfish density; species composition and adult body size generally exhibited little change. Recovery occurred equally well in reserves and areas open to other forms of fishing, implying strong compliance. Temporal trends in parrotfish grazing intensity were strongly negatively associated with the cover of macroalgae, which by 2018 had fallen to the lowest levels observed since measurements began in 1998. Coral populations remained resilient and continued to exhibit periods of net recovery after disturbance. We found that a moratorium on parrotfish harvesting is feasible and appears to help constrain macroalgae, which can otherwise impede coral resilience.
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Affiliation(s)
- Peter J Mumby
- Marine Spatial Ecology Lab & ARC Centre of Excellence for Coral Reef Science, School of Biological Sciences, The University of Queensland, St. Lucia, Queensland, Australia
| | - Robert S Steneck
- Darling Marine Center, School of Marine Sciences, University of Maine, Walpole, Maine, USA
| | - George Roff
- Marine Spatial Ecology Lab & ARC Centre of Excellence for Coral Reef Science, School of Biological Sciences, The University of Queensland, St. Lucia, Queensland, Australia
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Affiliation(s)
- Nils C Krueck
- Institute for Marine and Antarctic Studies (IMAS), University of Tasmania, Hobart, Tasmania, Australia.
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Recent expansion of marine protected areas matches with home range of grey reef sharks. Sci Rep 2021; 11:14221. [PMID: 34244536 PMCID: PMC8270914 DOI: 10.1038/s41598-021-93426-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 06/17/2021] [Indexed: 02/06/2023] Open
Abstract
Dramatic declines in reef shark populations have been documented worldwide in response to human activities. Marine Protected Areas (MPAs) offer a useful mechanism to protect these species and their roles in coral reef ecosystems. The effectiveness of MPAs notably relies on compliance together with sufficient size to encompass animal home range. Here, we measured home range of 147 grey reef sharks, Carcharhinus amblyrhynchos, using acoustic telemetry in New Caledonia. The distribution of home range was then compared to local MPA sizes. We report a home range of 12 km2 of reef for the species with strong differences between adult males (21 km2), adult females (4.4 km2) and juveniles (6.2 km2 for males, 2.7 km2 for females). Whereas local historic MPA size seemed adequate to protect reef shark home range in general, these were clearly too small when considering adult males only, which is consistent with the reported failure of MPAs to protect sharks in New Caledonia. Fortunately, the recent implementation of several orders of magnitude larger MPAs in New Caledonia and abroad show that recent Indo-Pacific MPAs are now sufficiently large to protect the home ranges of this species, including males, across its geographical range. However, protection efforts are concentrated in a few regions and cannot provide adequate protection at a global scale.
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McClure EC, Hoey AS, Sievers KT, Abesamis RA, Russ GR. Relative influence of environmental factors and fishing on coral reef fish assemblages. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2021; 35:976-990. [PMID: 32939886 DOI: 10.1111/cobi.13636] [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: 09/25/2019] [Revised: 08/16/2020] [Accepted: 08/28/2020] [Indexed: 06/11/2023]
Abstract
Understanding whether assemblages of species respond more strongly to bottom-up (availability of trophic resources or habitats) or top-down (predation pressure) processes is important for effective management of resources and ecosystems. We determined the relative influence of environmental factors and predation by humans in shaping the density, biomass, and species richness of 4 medium-bodied (10-40 cm total length [TL]) coral reef fish groups targeted by fishers (mesopredators, planktivores, grazer and detritivores, and scrapers) and the density of 2 groups not targeted by fishers (invertivores, small fish ≤10 cm TL) in the central Philippines. Boosted regression trees were used to model the response of each fish group to 21 predictor variables: 13 habitat variables, 5 island variables, and 3 fishing variables (no-take marine reserve [NTMR] presence or absence, NTMR size, and NTMR age). Targeted and nontargeted fish groups responded most strongly to habitat variables, then island variables. Fishing (NTMR) variables generally had less influence on fish groups. Of the habitat variables, live hard coral cover, structural complexity or habitat complexity index, and depth had the greatest effects on density, biomass, and species richness of targeted fish groups and on the density of nontargeted fishes. Of the island variables, proximity to the nearest river and island elevation had the most influence on fish groups. The NTMRs affected only fishes targeted by fishers; NTMR size positively correlated with density, biomass, and species richness of targeted fishes, particularly mesopredatory, and grazing and detritivorous fishes. Importantly, NTMRs as small as 15 ha positively affected medium-bodied fishes. This finding provides reassurance for regions that have invested in small-scale community-managed NTMRs. However, management strategies that integrate sound coastal land-use practices to conserve adjacent reef fish habitat, strategic NTMR placement, and establishment of larger NTMRs will be crucial for maintaining biodiversity and fisheries.
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Affiliation(s)
- Eva C McClure
- College of Science and Engineering, James Cook University, Townsville, Queensland, 4811, Australia
- Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Queensland, 4811, Australia
- Australian Rivers Institute - Coast and Estuaries, Griffith University, Gold Coast, Queensland, 4215, Australia
| | - Andrew S Hoey
- Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Queensland, 4811, Australia
| | - Katie T Sievers
- College of Science and Engineering, James Cook University, Townsville, Queensland, 4811, Australia
- Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Queensland, 4811, Australia
| | - Rene A Abesamis
- College of Science and Engineering, James Cook University, Townsville, Queensland, 4811, Australia
- Silliman University Angelo King Center for Research and Environmental Management, Silliman University, Dumaguete, 6200, Philippines
| | - Garry R Russ
- College of Science and Engineering, James Cook University, Townsville, Queensland, 4811, Australia
- Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Queensland, 4811, Australia
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Gnanalingam G, Gaff H, Butler MJ. Conserving spawning stocks through harvest slot limits and no-take protected areas. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2020; 34:1492-1502. [PMID: 32390269 DOI: 10.1111/cobi.13535] [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: 06/06/2019] [Revised: 03/05/2020] [Accepted: 03/13/2020] [Indexed: 06/11/2023]
Abstract
The key to the conservation of harvested species is the maintenance of reproductive success. Yet for many marine species large, old, individuals are targeted despite their disproportionate contribution to reproduction. We hypothesized that a combination of no-take marine protected areas (MPAs) and harvest slot limits (maximum and minimum size limits) would result in the conservation of large spawning individuals under heavy harvest. We tested this approach under different harvest intensities with a 2-sex, stage-structured metapopulation model for the Caribbean spiny lobster (Panulirus argus). P. argus is intensively harvested in the Caribbean, and in many localities large, mature individuals no longer exist. No-take MPAs and harvest slot limits combined, rebuilt and maintained large mature individuals even under high harvest pressure. The most conservative model (a 30% MPA and harvest slot limit of 75-105 mm) increased spawner abundance by 5.53E12 compared with the fishing status quo at the end of 30 years. Spawning stock abundance also increased by 2.76-9.56E12 individuals at a high harvest intensity over 30 years with MPAs alone. Our results demonstrate the potential of MPAs and harvest slot limits for the conservation of large breeding individuals in some marine and freshwater environments. Decisions on which management strategy best suits a fishery, however, requires balancing what is ecologically desirable with what is economically and socially feasible.
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Affiliation(s)
- Gaya Gnanalingam
- Department of Biological Sciences, Old Dominion University, 5115 Hampton Boulevard, Norfolk, VA, 23529, U.S.A
- Department of Marine Science, University of Otago, P.O. Box 56, Dunedin, 9054, New Zealand
| | - Holly Gaff
- Department of Biological Sciences, Old Dominion University, 5115 Hampton Boulevard, Norfolk, VA, 23529, U.S.A
| | - Mark J Butler
- Department of Biological Sciences, Old Dominion University, 5115 Hampton Boulevard, Norfolk, VA, 23529, U.S.A
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Cabral RB, Bradley D, Mayorga J, Goodell W, Friedlander AM, Sala E, Costello C, Gaines SD. A global network of marine protected areas for food. Proc Natl Acad Sci U S A 2020; 117:28134-28139. [PMID: 33106411 PMCID: PMC7668080 DOI: 10.1073/pnas.2000174117] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 09/15/2020] [Indexed: 01/26/2023] Open
Abstract
Marine protected areas (MPAs) are conservation tools that are increasingly implemented, with growing national commitments for MPA expansion. Perhaps the greatest challenge to expanded use of MPAs is the perceived trade-off between protection and food production. Since MPAs can benefit both conservation and fisheries in areas experiencing overfishing and since overfishing is common in many coastal nations, we ask how MPAs can be designed specifically to improve fisheries yields. We assembled distribution, life history, and fisheries exploitation data for 1,338 commercially important stocks to derive an optimized network of MPAs globally. We show that strategically expanding the existing global MPA network to protect an additional 5% of the ocean could increase future catch by at least 20% via spillover, generating 9 to 12 million metric tons more food annually than in a business-as-usual world with no additional protection. Our results demonstrate how food provisioning can be a central driver of MPA design, offering a pathway to strategically conserve ocean areas while securing seafood for the future.
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Affiliation(s)
- Reniel B Cabral
- Bren School of Environmental Science and Management, University of California, Santa Barbara, CA 93117;
- Marine Science Institute, University of California, Santa Barbara, CA 93117
- Environmental Market Solutions Lab, University of California, Santa Barbara, CA 93117
| | - Darcy Bradley
- Bren School of Environmental Science and Management, University of California, Santa Barbara, CA 93117
- Marine Science Institute, University of California, Santa Barbara, CA 93117
- Environmental Market Solutions Lab, University of California, Santa Barbara, CA 93117
| | - Juan Mayorga
- Bren School of Environmental Science and Management, University of California, Santa Barbara, CA 93117
- Marine Science Institute, University of California, Santa Barbara, CA 93117
- Environmental Market Solutions Lab, University of California, Santa Barbara, CA 93117
- Pristine Seas, National Geographic Society, Washington, DC 20036
| | - Whitney Goodell
- Pristine Seas, National Geographic Society, Washington, DC 20036
| | - Alan M Friedlander
- Pristine Seas, National Geographic Society, Washington, DC 20036
- Hawai'i Institute of Marine Biology, University of Hawai'i, Kāne'ohe, HI 96744
| | - Enric Sala
- Pristine Seas, National Geographic Society, Washington, DC 20036
| | - Christopher Costello
- Bren School of Environmental Science and Management, University of California, Santa Barbara, CA 93117
- Marine Science Institute, University of California, Santa Barbara, CA 93117
- Environmental Market Solutions Lab, University of California, Santa Barbara, CA 93117
| | - Steven D Gaines
- Bren School of Environmental Science and Management, University of California, Santa Barbara, CA 93117
- Marine Science Institute, University of California, Santa Barbara, CA 93117
- Environmental Market Solutions Lab, University of California, Santa Barbara, CA 93117
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Januchowski‐Hartley FA, Vigliola L, Maire E, Kulbicki M, Mouillot D. Low fuel cost and rising fish price threaten coral reef wilderness. Conserv Lett 2020. [DOI: 10.1111/conl.12706] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Affiliation(s)
- Fraser A. Januchowski‐Hartley
- UMR 9190 MARBECIRD‐CNRS‐UM‐IFREMER, Institut de recherche pour le développement (IRD) Montpellier Cedex 5 France
- UMR 9220 ENTROPIEInstitut de Recherche pour le Développement (IRD), Centré IRD de Nouméa Nouméa New Caledonia
- Department of Biosciences, College of ScienceSwansea University Abertawe UK
| | - Laurent Vigliola
- UMR 9220 ENTROPIEInstitut de Recherche pour le Développement (IRD), Centré IRD de Nouméa Nouméa New Caledonia
| | - Eva Maire
- UMR 9190 MARBECIRD‐CNRS‐UM‐IFREMER, Université de Montpellier Montpellier Cedex 5 France
- Lancaster Environment CentreLancaster University Lancaster UK
| | - Michel Kulbicki
- UMR 9920 ENTROPIE, Laboratoire Excellence LABEX CorailInstitut de recherche pour le développement Perpignan France
| | - David Mouillot
- UMR 9190 MARBECIRD‐CNRS‐UM‐IFREMER, Université de Montpellier Montpellier Cedex 5 France
- Australian Research Council Centre of Excellence for Coral Reef StudiesJames Cook University Townsville Queensland Australia
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Dwyer RG, Krueck NC, Udyawer V, Heupel MR, Chapman D, Pratt HL, Garla R, Simpfendorfer CA. Individual and Population Benefits of Marine Reserves for Reef Sharks. Curr Biol 2020; 30:480-489.e5. [PMID: 31983638 DOI: 10.1016/j.cub.2019.12.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Revised: 11/03/2019] [Accepted: 12/02/2019] [Indexed: 02/09/2023]
Abstract
No-take marine protected areas (MPAs) are a commonly applied tool to reduce human fishing impacts on marine and coastal ecosystems. However, conservation outcomes of MPAs for mobile and long-lived predators such as sharks are highly variable. Here, we use empirical animal tracking data from 459 individual sharks and baited remote underwater video surveys undertaken in 36 countries to construct an empirically supported individual-based model that estimates the conservation effectiveness of MPAs for five species of coral reef-associated sharks (Triaenodon obesus, Carcharhinus melanopterus, Carcharhinus amblyrhynchos, Carcharhinus perezi, and Ginglymostoma cirratum). We demonstrate how species-specific individual movement traits can contribute to fishing mortality of sharks found within MPAs as they move outside to adjacent fishing grounds. We discovered that the world's officially recorded coral reef-based managed areas (with a median width of 9.4 km) would need to be enforced as strict no-take MPAs and up to 5 times larger to expect protection of the majority of individuals of the five investigated reef shark species. The magnitude of this effect depended on local abundances and fishing pressure, with MPAs required to be 1.6-2.6 times larger to protect the same number of Atlantic and Caribbean species, which occur at lower abundances than similar species in the western Pacific. Furthermore, our model was used to quantify partially substantial reductions (>50%) in fishing mortality resulting from small increases in MPA size, allowing us to bridge a critical gap between traditional conservation planning and fisheries management. Overall, our results highlight the challenge of relying on abundance data alone to ensure that estimates of shark conservation impacts of MPAs follow the precautionary approach.
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Affiliation(s)
- Ross G Dwyer
- School of Biological Sciences, The University of Queensland, St Lucia, QLD 4072, Australia; Centre for Sustainable Tropical Fisheries and Aquaculture and College of Science and Engineering, James Cook University, Townsville, QLD 4811, Australia.
| | - Nils C Krueck
- School of Biological Sciences, The University of Queensland, St Lucia, QLD 4072, Australia; Institute for Marine and Antarctic Studies, University of Tasmania, Private Bag 49, Hobart, TAS 7001, Australia.
| | - Vinay Udyawer
- Australian Institute of Marine Science, Arafura Timor Research Facility, Darwin, NT 0810, Australia; Research Institute for the Environment and Livelihoods, Charles Darwin University, Darwin, NT 0909, Australia
| | - Michelle R Heupel
- Australian Institute of Marine Science, Townsville, QLD 4810, Australia
| | - Demian Chapman
- Department of Biological Science, College of Arts and Science, Florida International University, 151st Street, North Miami, FL, USA
| | - Harold L Pratt
- Mote Marine Laboratory, Elizabeth Moore International Center for Coral Reef Research & Restoration, Summerland Key, FL, USA; Anderson Cabot Center for Ocean Life, New England Aquarium, 1 Central Wharf, Boston, MA 02110, USA
| | - Ricardo Garla
- Departamento de Botânica e Zoologia, Universidade Federal do Rio Grande do Norte, Avenida Senador Salgado Filho, 3000, 59064-741 Natal, RN, Brazil
| | - Colin A Simpfendorfer
- Centre for Sustainable Tropical Fisheries and Aquaculture and College of Science and Engineering, James Cook University, Townsville, QLD 4811, Australia
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