Recovery potential of the world's coral reef fishes

摘要

Continuing degradation of coral reef ecosystems has generated substantial interest in how management can support reef resilience. Fishing is the primary source of diminished reef function globally, leading to widespread calls for additional marine reserves to recover fish biomass and restore key ecosystem functions. 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.%世界上很多珊瑚礁都受到过度捕捞,这促使人们普遍呼吁寻找解决"珊瑚礁危机"的办法。对超过800个珊瑚礁的恢复潜力所做的这项研究显示,被捕捞礁石的83%都失去了它们预期生物质的一半以上,对关键生态系统功能造成严重后果。通过禁止捕捞来进行保护,平均在35年内可以让珊瑚礁完全恢复,但退化最严重的珊瑚礁需要59年才能恢复。作者得出结论认为,退化珊瑚礁中至关重要的生态系统功能可以通过限制渔场作业与(在建立海洋保护区不实际的区域)其他保护方法相结合得以维持。