Historical overfishing and the recent collapse of coastal ecosystems

Ecological extinction caused by overfishing precedes all other pervasive hu man disturbance to coastal ecosystems, including pollution, degradation of water quality, and anthropogenic climate change. Historical abundances of l arge consumer species were fantastically large in comparison with recent ob servations. Paleoecological, archaeological, and historical data show that time lags of decades to centuries occurred between the onset of overfishing and consequent changes in ecological communities, because unfished species of similar trophic level assumed the ecological roles of overfished specie s until they too were overfished or died of epidemic diseases related to ov ercrowding. Retrospective data not only help to clarify underlying causes a nd rates of ecological change, but they also demonstrate achievable goals f or restoration and management of coastal ecosystems that could not even be contemplated based on the limited perspective of recent observations alone.