Gray Whale

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Gray Whale Fossil range: Middle Oligocene - Recent
A Gray Whale spy-hopping Size comparison against an average human
Conservation status
Eastern Pacific Western Pacific
Scientific classification
Kingdom: Animalia Phylum: Chordata Class: Mammalia Subclass: Eutheria Order: Cetacea Suborder: Mysticeti Family: Eschrichtiidae Ellerman & Morrison-Scott, 1951 Genus: Eschrichtius Species: E. robustus
Binomial name
Eschrichtius robustus Lilljeborg, 1861
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 16 meters (52 ft), 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).

Contents 1 Population, distribution and migration 2 Feeding 3 Physical description 4 Migration 5 Conservation and human interaction 6 Captivity 7 In the news 8 References 9 External links

[edit] 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 Gulf of California, 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 provides ecotourists and marine mammal enthusiasts the opportunity to see groups of Gray Whales as they pass by on their migration.

[edit] Feeding

The whale feeds mainly on benthic crustaceans which it eats by turning on its side (usually the right) and scooping up the sediments from the sea floor. It is classified as a baleen whale and has a baleen, or whalebone, which acts like a sieve to capture small sea animals including 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, depending primarily on its extensive fat reserves.

[edit] Physical description

Gray Whales are covered by characteristic gray-white patterns, scars left by parasites which drop off in the cold feeding grounds.

[edit] Migration

The migration route of the Pacific Gray Whale is often described as the longest known mammal migration in the animal kingdom. Beginning in the Bering and Chukchi seas and ending in the warm-water lagoons of Mexico’s Baja peninsula, their round trip journey moves them through 12,500 miles of coastline.

This journey begins each October as the northern ice pushes southward. Travelling both night and day, Gray whales average approximately 120 km (80 miles) per day. By mid-December to early January, the majority of the Gray whales are usually found between Monterey and San Diego, where they are often seen from shore.

By late December to early January, the first of the Gray Whales begin to arrive the calving lagoons of Baja. These first whales to arrive are usually pregnant mothers that look for the protection of the lagoons to give birth to their calves, along with single females seeking out male companions in order to mate. By mid-February to mid-March the bulk of the Gray Whales have arrived the lagoons. It is at this time that the lagoons are filled to capacity with nursing, calving and mating Gray Whales.

Throughout February and March, the first Gray Whales to leave the lagoons are the males and single females. Once they have mated, they will begin the trek back north to their summer feeding grounds in the Bering and Chukchi seas. Pregnant females and nursing mothers with their newborn calves are the last to leave the lagoons. They leave only when their calves are ready for the journey, which is usually from late March to mid-April. Often there are still a few lingering Gray Whale mothers with their young calves in the lagoons well into May.

[edit] 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 north-eastern Russia, 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. As of 2004, the population of Western Pacific (seas near Korea, Japan, and Kamchatka) Gray Whales was an estimated 101 individuals.

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.^[1]

[edit] 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.

[edit] In the news

A Gray Whale, thought to have got lost on its migration, was seen in the Fraser River in British Columbia, Canada on January 25, 2007. It then headed the right way back to the ocean, albeit slowly.

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.^[2]

[edit] References

General references

• Cetacean Specialist Group (1996). Eschrichtius robustus. 2006 IUCN Red List of Threatened Species. IUCN 2006. Retrieved on 11 May 2006. Database entry includes a lengthy justification of why this species is dependent on conservation
• Eschrichtius robustus (TSN 180521). Integrated Taxonomic Information System. Accessed on 18 March 2006.

[edit] External links

• Interactive Migration Map at the PBS Ocean Adventures site
• 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).

v • d • e Cetaceans
(whales, dolphins, and porpoises)
Suborder Mysticeti (baleen whales)	Eschrichtiidae (gray whales) · Balaenopteridae (rorquals) · Balaenidae (right whales) · Neobalaenidae (pygmy right whales)
Suborder Odontoceti (toothed whales)	Platanistoidea (river dolphins) · Delphinidae (oceanic dolphins) · Phocoenidae (porpoises) · Monodontidae (beluga and narwhal) · Physeteridae (sperm whales) · Kogiidae (pygmy and dwarf sperm whales) · Ziphiidae (beaked whales)