Shark attack

By Jef Akst Shark attack Diveofficer/Flickr Creative Commons The paper: R.A. Myers et al., “Cascading effects of the loss of apex predatory sharks from a coastal ocean,” Science, 315:1846–50, 2007. (Cited in 73 papers) The finding: Using over 30 years of species abundance data from 17 different fishery and scientific surveys, a team led by Charles Peterson of the University

Jef Akst
Aug 1, 2009

Shark attack

Diveofficer/Flickr Creative Commons

The paper:

R.A. Myers et al., “Cascading effects of the loss of apex predatory sharks from a coastal ocean,” Science, 315:1846–50, 2007. (Cited in 73 papers)

The finding:

Using over 30 years of species abundance data from 17 different fishery and scientific surveys, a team led by Charles Peterson of the University of North Carolina at Chapel Hill showed that the overfishing of great sharks along the east coast of the United States led to a proliferation of smaller sharks and rays, which in turn devastated scallop, clam, and other bivalve communities.

The relevance:

By demonstrating the ecological consequences associated with diminishing shark populations, the study was the first to convincingly link these top predators to shellfish populations, says James Estes, a marine ecologist at the University of California, Santa Cruz. “It adds another dimension to why we should strive to maintain or recover...

The shut down:

In the 1980s, the North Carolina bay scallop fishery was a million dollar industry. After the decline of the great shark, “the [scallop] population died out pretty hard,” says Tina Moore, a fisheries biologist at the NC Division of Marine Fisheries. By 2006, scallop numbers had dropped so low that the century-old fishery was forced to close its doors.

The future:

“We have just touched the tip of the iceberg about the consequences of removal of the great sharks for coastal ecosystems,” says Peterson, who only assessed the ecological impact of one of the 12 medium-sized predator species that increased in abundance after the decline of the great sharks in the Hot Paper. “There are so many more stories to be told.”

Changes in abundance since 1972:
Blacktip shark: 93% decrease
Cownose rays: 700-800% increase