Historical Overfishing and the Recent Collapse of Coastal Ecosystems

Bates College, Льюистон, Maine, United States
Science (Impact Factor: 33.61). 08/2001; 293(5530):629-37. DOI: 10.1126/science.1059199
Source: PubMed


Ecological extinction caused by overfishing precedes all other pervasive human disturbance to coastal ecosystems, including
pollution, degradation of water quality, and anthropogenic climate change. Historical abundances of large consumer species
were fantastically large in comparison with recent observations. 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 species until they too were overfished
or died of epidemic diseases related to overcrowding. Retrospective data not only help to clarify underlying causes and rates
of ecological change, but they also demonstrate achievable goals for restoration and management of coastal ecosystems that
could not even be contemplated based on the limited perspective of recent observations alone.

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