for National Geographic News
Sharks follow well-traveled "superhighways" among feeding hot spots, new research suggests. The discovery should allow scientists to create better conservation strategies for the fish.
Some great white sharks travel predictable pathways, spending long winters in two areas near Hawaii, according to research led by Salvador Jorgensen of Stanford University in California.
Jorgensen and colleagues suggest that other shark species have the same habits, and other research already supports the idea.
Peter Klimley of the University of California, Davis, for example, has noticed that scalloped hammerhead sharks in the Gulf of California use islands as stepping-stones, spending six to ten months at a time at certain islands before moving on.
Understanding shark migration routes can be key to saving the declining fish, experts say.
Many shark species are listed as endangered on the World Conservation Union (IUCN) Red List. And that doesn't count hundreds of vulnerable, deep-water species which are the hardest to study.
"We should concentrate [on] protection [of shark-rich] islands," said Klimley, who has received funding from the National Geographic Society's Committee for Research and Exploration and Expeditions Council. (National Geographic News is part of the National Geographic Society.)
The researchers presented their findings last week at the annual meeting of the American Association for the Advancement of Science in Boston, Massachusetts.
In Deep Water
The new insight into shark migration comes at a time when numbers of imperiled shark species have skyrocketed.
(Related: "Mediterranean Sharks, Rays Facing Oblivion, Study Says" [November 16, 2007].)
The fish are threatened mostly by overfishing. Demand for shark fins and meat, recreational shark fishing, and tuna and swordfish fishing that ensnares unwanted sharks are particular concerns.
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