Productive instability of coral reef fisheries after climate-driven regime shifts

• Published in: Nature ecology & evolution Vol. 3; no. 2; pp. 183 - 190
• Main Authors: Robinson, James P. W., Wilson, Shaun K., Robinson, Jan, Gerry, Calvin, Lucas, Juliette, Assan, Cindy, Govinden, Rodney, Jennings, Simon, Graham, Nicholas A. J.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.02.2019; Nature Publishing Group
• Subjects: 631/158; 631/158/2165; 631/158/2450; Biological and Physical Anthropology; Biomedical and Life Sciences; Climate; Coral bleaching; Coral reef ecosystems; Coral reefs; Divergence; Ecology; Evolutionary Biology; Fisheries; Fishing; Food security; Geographical distribution; Life Sciences; Nutrition; Paleontology; Productivity; Reef fish; Seaweeds; Species; Supply chains; Zoology
• ISSN: 2397-334X; 2397-334X
• DOI: 10.1038/s41559-018-0715-z

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. Twenty years of catch data and habitat surveys in coral reef fisheries in the Seychelles reveal that total yields can be maintained after severe bleaching and associated regime shifts, but the stability of fisheries is reduced.