A Scientific Study titled Global baselines and benchmarks for fish biomass: comparing remote reefs and fisheries closures, (Tim McClanahan et al) has just been published in the Marine Ecology Progress Series (MEPS), a leading journal in the field covering all aspects of marine ecology, fundamental and applied. Below is an excerpt from the introduction.
Measurable baselines and benchmarks (B&Bs) are critical for evaluating and comparing the status of natural ecosystems. Fisheries are particularly difficult to assess and manage without knowing carrying capacity, unfished biomass, and rates of fishing mortality and recovery. Numerous factors at many scales are expected to influence B&Bs and potentially preclude their utility except under very limited circumstances. Given the pervasiveness of human impacts, it is increasingly difficult to find natural B&Bs, even in the seemingly vast ocean. For example, unsustainable fishing, climate change, pollution, warm temperature anomalies, and an increasing frequency and intensity of storms are threatening marine ecosystems. Even remote reef areas experience human impacts of fishing and the effects of climate disturbances, making large-scale natural baselines increasingly rare.