Besides being eaten by humans, the meat has also been used in dog food and, when dried and crushed, cattle feed.Ĭommercial whaling of blue whales ended in 1966 due to the decline of the species. Whalebones were also used in the manufacture of glue, gelatin and manure. The principal attraction of whaling was the whale's blubber, which yielded oil ideal for lamp oil and, much later, in the production of margarine. Current Threats, Status, and ConservationĪll of the large whale species have been at risk of extinction due to a long history of whaling. Blue whales may live to an age of 80-90 years, or even longer. The only predator of the blue whale, aside from humans, is the killer whale (Orchinus orca). Males play no role in raising their young. They will nurse on their mother’s milk for 6-7 months. New born calves are approximately 20-23 feet long, weigh up to 4 tons, and grow quickly feeding on the milk of their mother. Blue whale pregnancy lasts for 10-12 months. Females will give birth once every 2-3 years. Blue whales are thought to be sexually mature at 5-15 years of age. Like other baleen whales, it is likely that long-term bonds are rare. Little is known about the blue whale mating. Mating, as well as the birth of calves, occurs during the winter. The winter breeding grounds are most likely located in warmer subtropical or tropical waters. These fat stores will be necessary for the long migration to their winter breeding and calving grounds. © Mike Davenportĭuring the summer, blue whales will spend most of their time feeding and building-up fat in the cold waters of the North Atlantic. Blue whales may also prey on small fish, but this is a small portion of their diet compared to krill. The prey items are then left within the mouth, trapped by the strips of baleen, and ready to be swallowed. They do so by taking a large mouthful of both prey and water, closing their mouth, and then pushing the water out of their mouth using their enormous tongue. They feed by filter feeding with their mouthful of baleen. Dietīlue whales primarily feed almost exclusively on tiny crustaceans known as krill. According to the New Jersey Endangered and Nongame Species Program, there are no sightings currently documented within New Jersey waters for this species. They typically are not seen over the continental shelf, preferring deeper waters. Their winter distribution is less well-known but some individuals have been observed in the Gulf of Mexico and the Caribbean. Within the North Atlantic Ocean, blue whales are typically found off the coast of Greenland and eastern Canada in the summer and may be found as far south as Cape Cod. Some individuals, however, may remain in their feeding grounds year-round. It appears that blue whales may follow a similar migration as humpbacks within the western North Atlantic Ocean, feeding during spring, summer, and fall in northern latitudes and then spending the winter in the West Indies. Their migration patterns are poorly understood compared to some whale species, such as the humpback whale ( Megaptera novaeangliae). They are not usually encountered within New Jersey’s coastal waters. Zoom+ Range of the Blue whale off the coast of New Jersey.īlue whales live within all of the major oceans of the world, primarily in temperate and polar waters. The coloration and patterning of the mottled skin is individually distinctive, similar to a human’s fingerprint, and allows researchers to identify and track individual whales. The dorsal fin is situated far back on the body and is not as tall or steeply angled as the fin or sei whale’s. Like the fin whale (and unlike the sei whale) the blowholes appear before (not with) the dorsal fin as the whale surfaces. It has two blowholes and the blow is high and columnar. These are used to strain food from large mouthfuls of water. Instead of teeth, it has great plates of horny baleen which extend from the upper jaw. The pectoral flippers are long and thin, while the dorsal fin is very small and far back. Almost U-shaped, the broad, flat rostrum or snout has a single median dorsal ridge. Underneath, the belly sometimes has a yellowish tinge as a result of diatoms that have attached themselves in cold water hence the nickname "Sulphur Bottom Whale." The belly's ventral grooves also extend to or just beyond the navel. The blue whale's skin is light bluish gray and mottled with gray or grayish-white it appears distinctly blue when seen through the water. As with other baleen whales, the female is larger than the male. The largest individual measured 110 feet long and nearly 200 tons. The largest animal alive and probably the largest animal that has ever existed, the blue whale has reached lengths greater than 100 feet and has reached weights of about 196 tons, although it averages 70 to 90 feet and weights of 100 to 150 tons. Species Group: Mammal Conservation Status New Jersey Endangered and Threatened Species Field Guide Zoom+ Blue whale tail.
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