GRAY WHALE (Eschrichtius robustus)
meaning of scientific name: Eschrichtius-named after the Danish professor who worked with these animals; robustus-strong
Gray whales are medium sized whales, reaching up to 49 feet (15 m) in length, with the females usually being larger than the males. They are gray with white patches, which mostly consist of areas where barnacles and lice have attached themselves to the whales. In fact, they carry over 400 pounds of barnacles and whale lice. Gray whales have no dorsal (back) fins. Instead, they have a low hump and a series of six to twelve knuckles or bumps. Gray whales are baleen whales, and each has approximately 300 plates of cream-colored baleen hanging from its upper jaw. Two to five throat creases allow their throats to expand during feeding. Sparse hairs are found on the snout, especially in young whales. Their blows are usually low and puffy or heart-shaped.
Gray whales are found only in the Pacific Ocean, with a population of approximately 26,000. The Eastern North Pacific stock is the largest group. They summer north of Alaska in the Bering and Chukchi Seas and winter in the waters of Baja California, Mexico. The Western North Pacific stock is found in the waters of Sakhalin Island, Russia and is close to extinction with only 100-150 individuals. Another group of gray whales once lived in the North Atlantic Ocean and became extinct in the 17th century, due to hunting. Gray whales generally stay around the continental shelf and are truly a coastal species.
Gray whales have one of the longest migrations of any mammal. During summer, they live in the Arctic in areas rich in their food, bottom-dwelling organisms. As fall approaches, there is less sunlight, less food, and the water turns cold. This is when the whales travel to Baja California, Mexico where they enter lagoons to give birth and mate. Gray whales can be seen passing by California in December and January during their southern migration, and again in March, April, and May on their northern journey.
Since gray whales migrate relatively close to shore, whalewatching is very popular. Many opportunities are available for viewing gray whales from coastal cliffs and headlands or from whalewatching boats. In the seventies, "friendly whales" were first encountered in San Ignacio Lagoon in Baja California, Mexico. Here, gray whales will sometimes swim near small boats and allow themselves to be touched. Concern has grown about the impact of boat traffic around whales, and the number of boats allowed in the breeding lagoons is restricted. Along the migration route, boats' proximity to whales is also limited.
Gray whales feed by sucking in bottom-dwelling animals, mostly amphipods (which are related to shrimp). Muddy patches of water are often seen in places where gray whales are feeding. They feed primarily in the Arctic, although some have been observed feeding during the migration.
MATING AND BREEDING
Female gray whales usually give birth every two to three years, and their pregnancies last twelve months. Newborn calves average 14-16 feet (4-5 m) in length and weigh about 2,000 pounds (907 kg). Calves are weaned at about eight months, after they have journeyed with their mothers back to the northern feeding grounds.
Gray whales have returned from the brink of extinction. In the late 1800s, the gray whale breeding grounds were discovered, and whalers killed a large percentage of the population. The drop in population made it no longer profitable to hunt gray whales; they were left alone and their numbers recovered. However, the early 1900s brought the invention of factory ships, which processed whales aboard the vessels. This new technology allowed intensive hunting on the grays once again, and their population again dangerously dropped to probably fewer than 2,000 individuals. Protection finally came in 1946 through an international agreement to stop hunting them. Since that time, the population has grown to 26,000, similar to what it was before modern-day whaling. As a result of this population recovery, gray whales were removed from the Endangered Species List in 1994.
In 1998 the International Whaling Commission reinstated a treaty made between the U.S. Government and the Makah Indians in 1855, giving the Native American group the permission to hunt gray whales. Under the new agreement, the Makah are able to take 20 whales through the year 2004. After a 70-year ban on gray whale hunting, the Makah took their first whale in May of 1999. The revival of the treaty is very controversial. Since the Makah have been allowed to continue gray whale hunting for its importance to their native culture, the environmentalists are calling for no exceptions to the hunting ban. This is because of the fear that the treaty revival will start a trend toward hunting other marine mammals.
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