SANTA BARBARA, Calif. — September 18, 2013 — A new UC Santa Barbara study shows that threats created by overfishing can be identified decades before the fish species at risk experience high overly harvest rates and subsequent population declines. Researchers developed an Eventual Threat Index (ETI) that quantifies the biological and socioeconomic conditions that eventually cause some fish species to be harvested at unsustainable rates. The findings are published in the Early Edition of the Proceedings of the National Academy of Sciences.
"Overharvesting poses a significant threat to biodiversity, particularly marine biodiversity, where a half-century of industrial fishing has caused the collapse of many populations and severely impacted many ecosystems," said David Tilman, professor of ecology, biodiversity, and ecosystem functioning at UCSB's Bren School of Environmental Science & Management and co-author of the paper. Multispecies fisheries, which use trawling, longlining, and seining, are some of the largest contributors and have the most ecological impact.