Gray whales in the North Pacific belong to two distinct populations, with the Western gray whale population seen mainly along the coasts of China, Korea, Japan and Russia. They have been hunted to the point of near extinction, and less than 100 remain.
The Moscow Times reported on Tuesday that five critically-endangered gray whale carcasses had been washed ashore on the Chukotka coast in Russia's northeasterly region. The whales belong to the Chukotka-California population and are on Russia's "Red List" of endangered species.
Map of Northeastern Russia, and the Chukotka Region.
According to Mammal Council deputy head Andrei Boltunov, "We need to register all the cases of these animals' death and investigate the reasons of the incident." It should be noted that the grey whale has been designated for "Special Concern" by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC).
This particular incident follows a similar finding in September of this year when the remains of 10 gray whale carcasses were found washed up on an 800-kilometer stretch of the Chukotka coast by a team of scientists doing an aerial survey. Large numbers of polar bears has been drawn to the area by the prospects of food, and this prompted scientists to warn local residents of the dangers of coming near the area.
This population of gray whales migrate each year from their calving grounds off the coast of Mexico to their summer feedings grounds in northern Alaska, Canada and Russia. While some gray whale groups have made a recovery in their numbers, this particular group has not shown any great increase in numbers, possibly due to a lack of food in Alaska.
False Pass, Alaska is also the name given the Isanoyski Strait that gray whales will sometimes use on their journey to the Bering Sea. Here many fall prey to Killer whales.
Gray whales grow to about 43-49 feet and can weigh from 14-35 tons. They are baleen feeders, filtering food as they feed in the ocean depths. When they are seen in the ocean, their skin looks like a "pile of rocks," the result of barnacles and sea lice covering them.
Gray whales calving in Mexico are susceptible to human activity, like getting tangled in fishing nets and collisions with boats and propellers. Underwater noise, associated with oil drilling is also a problem, possibly altering migration routes. Even subsistence whaling in the U.S. could affect this group's numbers.
The main predator of the gray whales is the killer whale, attacking calves and yearlings along the migration route. Most of the gray whales use the False Pass, along Alaska, through which the group must pass on their journey to the Bering Sea. The carcasses that remain and wash ashore provide vital food for the bears in that region.