Gray Whale

The gray whale has no dorsal fin, but there is a line of bumps along the middle of its lower back. Its jaw is only slightly arched and the snout is pointed. Males are larger than females. Like all baleen whales, it feeds on small planktonic animals by filtering water through rows of fringed horny plates, suspended from the upper jaw. Any creatures in the water are caught on the baleen plates, and the water is expelled at the sides of the mouth. Using its tongue, the whale takes the food from the baleen to the back of its mouth to be swallowed. The gray whale feeds at the bottom of the sea, unlike other baleen whales, stirring up the sediment with its pointed snout, then sieving the turbulent water.  Gray whales perform migrations of some 20,000 km (12,500 mi) between feeding grounds in the north and breeding grounds in the south. They spend the summer months in the food-rich waters of the Arctic, when they do most of their feeding for the year. At the breeding grounds, they gather to perform courtship rituals, and breeding animals pair off with an extra male in attendance. They lie in shallow water, and as the pair mate, the second male lies behind the female, apparently supporting her. The gestation period is 12 months, so the calf is born at the breeding grounds a year after mating has taken place and travels north with its mother when it is about 2 months old.