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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 shark populations.”
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 |
Whilst the Bull nosed ray population explosion is significant, could there be other reasons like over fishing helping to decimate the scallop population?
Always been a shark lover. It's sad to see their populations dwindle.
Extinction of certain species leads to disturbance in ecosystem i can understand this point but it would have been much better if this paper also show statistical analysis and method of data collection. This addition will be worth reading and will simplify understanding of current situation of marine life at present.
Is this just an advertisement for this paper? Where's the critical analysis? This is the type of journalism I expect from the National Enquirer.