Scars from killer whale teeth are often observed on gray whales. There are numerous reports of killer whales feeding on tongues of gray whales and leaving the carcasses. Calves appear to be weaned in nine months, in time for the fall migration.ĭiet: amphipod crustaceans, polychaete worms, crab larvae, small fish, crabs and possibly plants and seaweed.Įnemies: killer whales ( Orcinus orca) may be a significant cause of gray whale deaths, particularly of young migrating whales. Females bear a single calf at intervals of two or more years. Sexual Maturity: 11.1m, males 11.7m, females and occurs between five and eleven years of age. This friendly whale nuzzled our small boat at San Ignacio Lagoon, Baja California, Mexico. The skin of this swimming gray whale sports hairs and barnacles. The top of their tapering jaw has pits or depressions, each containing one stiff hair. Whale lice are orange-colored crustaceans that inhabit the same areas and folds and grooves, as well as the open surface of the skin. A distinctive feature is their barnacle clusters, which are usually on their head and back. Its color is mottled gray, sometimes with patches that are very pale or white. It has no dorsal fin, but a series of from six to twelve knuckle-like knobs along the dorsal ridge. The gray whale is about 17 feet long at birth and reaches a maximum size of approximately 45 feet females are larger than males. This feeding technique is also considered primitive. They scoop mouthfuls of bottom sediment and, after filtering it through their baleen, retain the living organisms. Unlike other baleen whales, gray whales usually feed on the ocean bottom. The plates consist of a material called keratin which is the same substance found in human fingernails. Baleen is a giant filter-feeding device and consists of fringed plates which overlap and hang from the upper jaw (130-180 on each side). It is the sole representative of the family Eschrichtiidae and the only whale to range in the comparatively shallow waters of the continental shelves. It is considered the most primitive whale, or the one most like the common ancestor of all whales. In addition to its marathon migration, the gray whale has other unusual characteristics. It is the only baleen whale to have recovered from commercial whaling. This is believed to be close to its pre-exploitation stock size. In 1946, by international agreement, gray whales were given protection from commercial whaling and their population has grown to its current estimate of 21,000. They would "fight like devils" and hence were named "devilfish."Īfter the turn of the century, gray whales were again decimated when floating factories (which process whales) were introduced. The beleaguered mothers would aggressively defend their calves by ramming and smashing boats. Whalemen would harpoon calves in order to get their mothers within range. Yankee whalers discovered the Baja lagoons in the 1850s and their slaughter of gray whales brought the population to commercial extinction in just 18 years. Their lengthy migration will take them to the temperate waters of Baja, California, where mating occurs and calves are usually born. The gray whales have spent May through November feeding in the food-rich Bering, Chuckchi and western Beaufort seas. Their journey begins in fall when temperatures begin to drop in the circumpolar seas surrounding Siberia and Alaska. New claim states humpback whales may make the longest migration. This 10,000-14,000 mile round trip is among the longest known of any mammal, and, in many instances, brings the whales within viewing distance from land. The gray whale is best known for its annual migration north and south along the coast of western North America. DERIVATION: Eschricht refers to a 19th Century Danish zoology professor from the Latin robustus for oaken or strong.
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