Grey Whale - Eschrichtius robustus
The Grey Whale travels between feeding and breeding grounds yearly. It reaches an approximate length of about 16 meters, a weight of 36 tonnes and an average age of 50 – 60 years. Three populations have been discovered, the first in the North Eastern Pacific, the second in North Western Pacific and the third extinct population in the North Atlantic. They are grey in appearance but with white patches formed from the barnacles or lice that attach to the whale. One whale can carry over 400 pounds of these barnacles or lice. Grey Whales have no dorsal or back fins, but rather have a series of six to twelve knuckles or bumps on their backs.
Grey Whales are known to have the longest yearly migration of any mammal on earth. In spring time in the Eastern Pacific, these whales begin their two to three month journey of some 8,000 – 11,000 kilometers south from the Bering and Chukchi seas, ending in the warm water lagoons of Mexico. Travelling both day and night, these whales average some 120 kilometers per day. By late December or early January, the first of the Grey whales start to arrive at the lagoons of Baja in California to calve. Because of the vast study of whales carried out by scientists, it is believed that the shallow waters in the lagoons protect the newborn whales from sharks. The first whales to arrive are usually the pregnant mothers, along with many single females who are seeking male companionship in order to mate. Once the mating is complete, the whales begin the long journey back north to summer feeding grounds. The breeding behavior is complex and often involves three or more animals. During February and March, the first of the Grey Whales to leave the lagoons are the males and single females. Usually the pregnant females, nursing mothers and the newborn calves are the last to leave the lagoon. The gestation period is about one year and females bear calves every other year. The calf is born tail first and measures about four meters in length. As these whales migrate relatively close to the shore, a whale watching industry provides tourists and other enthusiasts the opportunity to view groups of Grey Whales as they pass by. There is much concern about the impact boat traffic has on these whales, therefore the number of boats allowed in the breeding lagoons is restricted. Along the migration route, boats' proximity to whales is also limited.
The Grey Whale feeds mostly on crustaceans by turning on its side and scooping these creatures up from the sea floor. It has a baleen which it uses to sieve and capture small sea animals. This whale feeds mostly in the northern waters during the summer, but sometimes feeds during its migration journey, depending on its fat reserves.
The Grey Whale's only predators are humans and the Killer Whale. In 1857, after the Grey Whale’s breeding ground was discovered, they were hunted almost to extinction. But the population slowly recovered and is no longer hunted on a large scale. From 2001, the species had grown to about 26,000 animals and is constantly growing due to its protected status and the continuous study of whale species.
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