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Students
Ask and Experts Answer
Conservation
Q. Are gray whales an endangered species?
A. The gray whale was removed from the endangered species list in
1994. A small number of gray whales are still legally hunted. Grays were
hunted to the edge of extinction in the 1850s after the discovery of the
calving lagoons, and again in the early 1900s with the introduction of
floating whaling factories. The gray whale was given partial protection
in 1937 and full protection in 1947 by the International Whaling Commission
(IWC). Since that time, the eastern North Pacific gray whale population
has made a remarkable recovery. In 1999 the National Marine Laboratory
reported 26,600 gray whales.
Q. Is there just one population of gray whales in the
world?
A. The eastern north Pacific population is the largest surviving population.
At one time there was a north Atlantic population, now extinct, possibly
the victims of over-hunting. A Korean or western north Pacific stock is
now very depleted, also possibly from over-hunting.
Q. What are a gray whales' enemies?
A. Their natural enemies are sharks and
orcas. Their unnatural enemies are ocean pollution, huge fishing nets,
and other human activities that harm their food chain or habitat.
Q. How do humans harm gray whales and their habitat?
A. Humans no longer hunt gray whales in most places. But they may
build resorts and crowd habitat with tourists, and discharge waste from
cruise ships, which all increase ocean pollution. They may build industries
that could harm whales' habitat. One example is the salt production facility
some want to build on the shores of the pristine nursery lagoons in Mexico.
Some experts believe that global warming, resulting in part from human
activities, may be harming the gray whale's food chain. The U.S. Navy
has performed low-frequency sonar testing at sea. Researchers have found
that gray whales exposed to high-intensity active sonar stray from their
migration routes. Beached whales of other species have been found bleeding
around their brains and ears — a tell-tale sign of trauma caused
by exposure to intense sound—after encounters with this deadly technology.
In one U.S. Navy study, blue whales' vocalization decreased by half when
exposed to even moderate levels of sonar. Found in oceans worldwide, these
endangered giants congregate in the krill-rich waters of California's
Channel Islands, on the gray whale migration route.
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