Abstract

Tropical coastal communities are highly reliant on coral reefs, which provide nutrition and employment for millions of people. Climate-driven coral bleaching events are fundamentally changing coral reef ecosystems and are predicted to reduce productivity of coral reef fish and fisheries, with significant implications for food security and livelihoods. Yet evidence of long-term bleaching impacts on coral reef fishery productivity is lacking. Here, we analyse over 20 years of fish abundance, catch and habitat data to assess long-term impacts of climate-driven coral mass mortality and regime shifts on nearshore artisanal coral reef fisheries in the Seychelles. Contrary to expectations, total catch and mean catch rates were maintained or increased after coral bleaching, consistent with increasing abundance of herbivorous target species in underwater surveys, particularly on macroalgal-dominated reefs. Catch instability increased as habitats followed divergent post-disturbance trajectories and the distribution of target species became more spatially variable, potentially impacting fisher incomes and local market supply chains. Although coral bleaching increased fishery dependence on herbivore species, our results show that climate-impacted reefs can still provide livelihoods and fish protein for coastal communities.

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Data availability

All analyses were conducted in R 3.4.254 using mgcv51 and vegan55. Model predictions and R analysis scripts are provided at github.com/jpwrobinson/prod-instability. The fishery-dependent dataset is not publicly available but may be requested from the authors with permission of SFA.

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Acknowledgements

This paper is dedicated to the memory of Edwin Mark Grandcourt, a pioneering Seychellois fisheries scientist who made significant contributions to establishing the underwater dataset and catch assessment surveys used in this paper, which now help shape our understanding of coral reef fisheries in Seychelles and across the world. This research was supported by the Royal Society (grant nos. CH160077 and UF140691), the Leverhulme Trust (grant no. F/00 125/M) and the Australian Research Council (grant nos. DP1094932 and DE130101705). We thank the fisheries observers and data technicians of SFA for data collection, and Seychelles Marine Parks Authority, Nature Seychelles and Global Vision International for field assistance.

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Affiliations

  1. Lancaster Environment Centre, Lancaster University, Lancaster, UK

    • James P. W. Robinson
    •  & Nicholas A. J. Graham
  2. Department of Biodiversity, Conservation and Attractions: Marine Science Program, Kensington, Western Australia, Australia

    • Shaun K. Wilson
  3. Oceans Institute, University of Western Australia, Crawley, Western Australia, Australia

    • Shaun K. Wilson
  4. Ministry of Finance, Trade, Investment and Economic Planning, Victoria, Seychelles

    • Jan Robinson
  5. Seychelles Fishing Authority, Mahe, Seychelles

    • Calvin Gerry
    • , Juliette Lucas
    • , Cindy Assan
    •  & Rodney Govinden
  6. International Council for the Exploration of the Sea, Copenhagen, Denmark

    • Simon Jennings

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Contributions

J.P.W.R., S.K.W. and N.A.J.G. conceived the study and wrote the first draft of the manuscript, with substantial input from S.J. Underwater ecological data were collected by S.K.W., S.J. and N.A.J.G. C.G., J.R., J.L., C.A. and R.G. designed and managed the Seychelles fisheries monitoring programme. J.P.W.R. conducted all statistical analyses.

Competing interests

The authors declare no competing interests.

Corresponding author

Correspondence to James P. W. Robinson.

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    Supplementary Methods, Supplementary Results, Supplementary Figures 1–16 and Supplementary Tables 1–4

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https://doi.org/10.1038/s41559-018-0715-z

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