The 5 November article in ScienceNews titled, “Lopped Off: Removal of top tredator trickles through the food web,” recounts an event that occurred in July, in which the Ecuadorean navy helped apprehend a fishing vessel within the waters of the Galápagos National Park. On board lay the carcasses of 379 sharks. The fins were presumably destined for trade in Asian markets, where shark-fin soup can sell for more than $100 a bowl.
The article addresses the issues that sharks aren’t the only predators under siege. A host of carnivores perched atop food webs are being eliminated by humans. Though scientists have long known that apex consumers play important ecosystem roles, studying those roles is tricky.
“Imagine looking out at an ecosystem that had wolves in it—just seeing a place with wolves—you wouldn’t have any sense of the importance of wolves unless you took them out,” says wildlife ecologist James Estes of the University of California, Santa Cruz, who outlined some of the consequences of losing predators in the 15 July 2011 issue of Science.
The findings in this and other studies suggest that the effects of predator loss can cross boundaries between land and sea, alter entire landscapes and even touch the smallest microorganisms and the Earth’s chemical cycles.
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Read the full article, Lopped Off: Removal of Top Predators Trickles Through the Food Web, on the ScienceNews website.
Read the Science paper here.
Read the Ecology paper here.
