Gray Whale
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{{Taxobox | color = pink | name = Gray Whale | status = Conservation status: Lower risk | image = Gray_whale.jpg | image_width = 250px | image_caption = A Gray Whale spy-hopping | regnum = Animalia | phylum = Chordata | classis = Mammalia | subclassis = Eutheria | ordo = Cetacea | subordo = Mysticeti | familia = Eschrichtiidae | familia_authority = Ellerman & Morrison-Scott, 1951 | genus = Eschrichtius | species = E. robustus | binomial = Eschrichtius robustus | binomial_authority = Lilljeborg, 1861 | range_map = cetacea_range_map_Gray_Whale.png | range_map_width = 250px | range_map_caption = Gray Whale range }} The Gray Whale or Grey Whale (Eschrichtius robustus), more recently called the Eastern Pacific Gray Whale, is a whale that travels between feeding and breeding grounds yearly. It reaches a length of about 15 meters, a weight of 36 tons and an age of 50–60 years. Gray Whales were once called devil fish because of their fighting behavior when hunted. The Gray Whale is the sole species in the genus Eschrichtius, which in turn is the sole genus in the family Eschrichtiidae. This animal is one of the oldest species of mammals, having been on Earth for about 30 million years. In the remote past it was preyed upon by Megalodon sharks (which are now extinct).
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Population, distribution and migration
Two Pacific Ocean populations of Gray Whales exist: one small population travelling between the Sea of Okhotsk and southern Korea, and a larger one travelling between the waters off Alaska and the Baja California. A third, North Atlantic, population was hunted to extinction 300 years ago.
In the fall, the California Gray Whale starts a 2–3 month, 8,000–11,000 km trip south along the west coast of the United States and Mexico. The animals travel in small groups. The destinations of the whales are the coastal waters of Baja California and the southern Sea of Cortez, where they breed and the young are born. The breeding behavior is complex and often involves three or more animals. The gestation period is about one year, and females have calves every other year. The calf is born tail first and measures about 4 meters in length. It is believed that the shallow waters in the lagoons there protect the newborn from sharks.
After several weeks, the return trip starts. This round trip of 16,000–22,000 km, at an average speed of 10 km/h, is believed to be the longest yearly migration of any mammal. A whale watching industry has sprung up along the coast.
Feeding
The whale feeds mainly on benthic crustaceans which it eats by turning on its side (usually the right) and scooping up the sediments (usually on the right) from the sea floor. It is classified as a baleen whale and has a baleen, or whalebone, which acts like a sieve to capture amphipods taken in along with sand, water and other material. Mostly, the animal feeds in the northern waters during the summer; and opportunistically feeds during its migration trip, and mainly lives off its extensive fat reserves.
Physical description
Gray Whales are covered by characteristic gray-white patterns, scars left by parasites which drop off in the cold feeding grounds.
Conservation and human interaction
The only predators of adult Gray Whales are humans and orcas. After the California Gray Whales' breeding grounds were discovered in 1857, the animals were hunted to near extinction there. After harvesting became inefficient because of dwindling numbers, the population recovered slowly, but with the advent of factory ships in the 20th century, the numbers declined again. Gray Whales have been granted protection from commercial hunting by the International Whaling Commission (IWC) since 1946, and are no longer hunted on a large scale.
Limited hunting of Gray Whales has continued since that time, however, primarily in the Chukotka region of eastern Siberia, where large numbers of Gray Whales spend the summer months. This hunt has been allowed under an "aboriginal/subsistence whaling" exception to the commercial-hunting ban. Anti-whaling groups have protested the hunt, saying that the meat from the whales is not for traditional native consumption, but is used instead to feed animals in government-run fur farms; they cite annual catch numbers that rose dramatically during the 1940s, at the time when state-run fur farms were being established in the region. Although the Soviet government denied these charges as recently as 1987, in recent years the Russian government has acknowledged the feeding of Gray Whale meat to animals on fur farms in the region. The Russian IWC delegation has said that the hunt is justified under the aboriginal/subsistence exemption, since the fur farms provide a necessary economic base for the region's native population.
Currently, the annual quota for the Gray Whale catch in the region is 140 whales per year. A smaller quota of 4 whales per year was established for the Makah Indian tribe of Washington at the IWC's 1997 meeting, but with the exception of a single Gray Whale killed in 1999, the Makah people have been prevented from conducting Gray Whale hunts by a series of legal challenges, culminating in a United States federal appeals court decision in December 2002 that said the National Marine Fisheries Service must prepare an Environmental Impact Statement before allowing the hunt to go forward.
As of 2001, the population of California Gray Whales had grown back to about 26,000 animals.
The Atlantic population of Gray Whales was hunted to extinction in the 17th century. However, in July 2005 scientists working at the University of Central Lancashire suggested that some Gray Whales be taken from the Pacific and re-introduced to the Atlantic—specifically, in the Irish Sea. Their idea would create a whale-watching industry in Cumbria in the United Kingdom and bolster the relatively fragile global population of Gray Whales. There is no indication at this time as to whether the idea will actually come to fruition. (BBC News)
Captivity
In 1972, a 3-month-old Gray Whale named Gigi was captured for brief study, and then released near San Diego.
In January 1997, the new-born baby whale J.J. was found helpless near the coast of Los Angeles, 4.2 m long and 800 kg in mass. Nursed back to health in SeaWorld San Diego, she was released into the Pacific Ocean on March 31, 1998, 9 m long and 8500 kg in mass. She shed her radio transmitter packs three days later.
In the news
A lone gray whale was seen in spring 2005 on the eastern coastline of Japan, and around Tokyo bay. It attracted crowds of whale watchers in April, but later became entangled in a fisherman's net, drowned and was washed up in early May. (BBC News)
References
External links
- ARKive - images and movies of the grey whale (Eschrichtius robustus).
- Information on JJ from Sea World
- U.S. International Whaling Commission (IWC) delegation's press release announcing the establishment of a combined Russian-Makah Gray Whale quota (1997)
- U.S. State Department report: Russia's Chukotka Autonomous Region Overview (1998), including the following passage documenting use of marine mammal meat in Chokotkan fur farms:
- Marine Mammal Hunting. Marine mammal hunting is part of the traditional lifestyle of the indigenous population in coastal Chukotkan communities. Native peoples are provided with an annual quota to procure 169 whales, 10,000 ringed seals, and 3,000 walruses. Marine mammal by-products are used as food in fox ranches.
- IWC report on aboriginal/subsistence whaling quota for 2004
- Humane Society of the U.S. page documenting the history of the Makah whaling litigation (2003)
- Two articles from the pro-native-whaling World Council of Whalers: Chukotkan whaling: Technology, tradition and hope combine to save a people (2000), and World whaling: Russia (2004).
- Article from the Seattle Post-Intelligencer on cooperation between the Chukchi and Makah native people in their efforts to resume traditional whaling activities: Two tribes reach out across miles -- and years -- with whaling link (2004).
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