Journal Article

Recovery potential of the world's coral reef fishes

Polunin, Nicholas V. C., Williams, Ivor D., Wilson, Shaun K., Friedlander, Alan M., Jupiter, Stacy, Graham, Nicholas A. J., MacNeil, M. Aaron, Maina, Joseph, Newman, Steven, McClanahan, Tim R., Cinner, Joshua E.

2015

Overview

A study of the recovery potential of over 800 of the world's coral reefs shows that 83% of fished reefs are missing more than half their expected biomass, with severe consequences for key ecosystem functions; protection from fishing would allow full recovery in 35 years on average, but in 59 years for the most degraded reefs. Restoring overfished coral reefs Many of the world's coral reefs are overfished, prompting widespread calls for solutions to the 'coral reef crisis'. This study of the recovery potential of more than 800 coral reefs shows that 83% of fished reefs are missing more than half their expected biomass, with severe consequences for key ecosystem functions. Protection from fishing would allow full recovery in 35 years on average, but 59 years for recovery of the most degraded reefs. The authors conclude that vital ecosystem functions in degraded coral reefs can be maintained through a combination of fisheries restrictions and — in regions where marine reserves are impractical — alternative conservation strategies. Continuing degradation of coral reef ecosystems has generated substantial interest in how management can support reef resilience 1 , 2 . Fishing is the primary source of diminished reef function globally 3 , 4 , 5 , leading to widespread calls for additional marine reserves to recover fish biomass and restore key ecosystem functions 6 . Yet there are no established baselines for determining when these conservation objectives have been met or whether alternative management strategies provide similar ecosystem benefits. Here we establish empirical conservation benchmarks and fish biomass recovery timelines against which coral reefs can be assessed and managed by studying the recovery potential of more than 800 coral reefs along an exploitation gradient. We show that resident reef fish biomass in the absence of fishing ( B 0 ) averages ∼1,000 kg ha −1 , and that the vast majority (83%) of fished reefs are missing more than half their expected biomass, with severe consequences for key ecosystem functions such as predation. Given protection from fishing, reef fish biomass has the potential to recover within 35 years on average and less than 60 years when heavily depleted. Notably, alternative fisheries restrictions are largely (64%) successful at maintaining biomass above 50% of B 0 , sustaining key functions such as herbivory. Our results demonstrate that crucial ecosystem functions can be maintained through a range of fisheries restrictions, allowing coral reef managers to develop recovery plans that meet conservation and livelihood objectives in areas where marine reserves are not socially or politically feasible solutions.

• Publisher: Nature Publishing Group UK,Nature Publishing Group
• Subject: 631/158/672 / Animals / Benchmarks / Biodiversity / Biomass / Conservation of Natural Resources - methods / Conservation of Natural Resources - statistics & numerical data / Conservation of Natural Resources - trends / Coral reef ecosystems / Coral Reefs / Coral reefs and islands / Ecological function / Ecosystem / Ecosystems / Fish / Fish conservation / Fish populations / Fisheries / Fisheries - methods / Fisheries - standards / Fisheries - statistics & numerical data / Fishes - physiology / Fishing / Herbivory / Humanities and Social Sciences / letter / Marine conservation / Marine ecosystems / multidisciplinary / Population Dynamics / Predatory Behavior / Protection and preservation / Restrictions / Science / Time Factors