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Broad-scale overharvesting of fish is one of the major drivers of marine biodiversity loss and poverty, particularly in countries with high dependence on coral reefs. Given the heterogeneity of fishing effort and management success, and the scarcity of management resources, it is necessary to identify broad-scale locations for promoting successful fisheries management and conservation. Here, we assessed how fisheries management and conservation priorities in the Western Indian Ocean would change if the objectives were to (1) minimize lost fishing opportunity, (2) minimize the time for fish biomass to recover, (3) avoid locations of low management feasibility based on historical management outcomes, and (4) incorporate international collaboration to optimize the rate for achieving goals. When prioritizing for rapid recovery of fish biomass rather than minimizing lost fishing opportunity, we found that the area of priority management zones changed by over 60% in some countries. When locations of low management feasibility were avoided, the recovery time of fish biomass across the region increased 4-fold. International collaborations prioritized management zones in remote, high biomass, and low fishing pressure reefs and reduced the recovery time of fish 5-fold compared to non-collaboration scenarios. Thus, many of these conservation objectives favored wealthy and sparsely populated over poorer and natural resource dependent countries. Consequently, this study shows how prioritization policies, incentives, decisions, and conflicts will produce highly variable outcomes and challenges for sustainability.

1. Climate change is emerging as one of the greatest threats to coral reef ecosystems. Climate-induced warming events trigger coral bleaching and mortality, which can indirectly affect coral reef fishes. Managing fisheries across coral mortality events is expected to influence the persistence of species and reef recovery potential. The most common management recommendation has been to prohibit fishing using fisheries closures, but this response often has limited support from resource users. 2. Here, we explore an alternative of managing fishing gear commonly used in artisanal coral reef fisheries. We examined fisheries landing data from 15 sites in Papua New Guinea and Kenya to explore whether or how specific gears select for: (i) species that depend on coral reefs for feeding or habitat and are likely to be susceptible to the loss of coral, and (ii) different functional groups of fishes. 3. Only 6% of the fishes targeted by fishers were susceptible to the immediate effects of coral mortality; however, loss of habitat structure following coral mortality is expected to affect 56% of targeted species. 4. Importantly, 25% of target species had feeding characteristics (i.e. reef scrapers/excavators and grazers) that contribute to the recovery of coral reef ecosystems, and gears differed considerably in catches of these species. 5. Spear guns and traps target a high proportion of species likely to be affected by bleaching and key for the recovery of corals. These gears are strong candidates for management restrictions in reefs with high coral mortality. In contrast, line fishing catches the lowest proportion of susceptible and recovery-enabling species and is preferential for increasing recovery rates on coral reefs. 6. Synthesis and applications. Fisheries managers will require a range of tools to meet the novel challenges posed by climate change. This study presents a way to help reduce the negative impacts of climate change and potentially increase resilience of marine ecosystems by managing fishing gear. Specific gears used by artisanal fishers differentially target fish functional groups. In the coral reefs that we studied, traps and spear guns targeted a high proportion of species highly susceptible to coral mortality and critical to coral reef resilience through their top-down control. Given that full fisheries closures are not always practical, selectively banning or restricting fishing gears is a potentially powerful tool for reducing the detrimental ecosystem effects of climate change disturbances. © 2008 British Ecological Society.