The heart of this issue lies in appropriation. Who owns a whale? When a sperm whale died off the coast of the Netherlands two weeks ago , it was towed back to land and lifted on to a quayside, where a necropsy was performed to determine cause of death pneumonia and ascertain how to deal with live strandings — a vital question on the shores of the shallow North Sea, where there has been a spate of such incidents in recent years.
Unlike Hvalur, the organisations involved were behaving absolutely honourably. Sometimes science can get in the way of the very thing it tries to understand.
Both sides use animals to further their aims. The animals lose out, twice over. In the past 12 months, 18 individuals have been killed by ship strikes or by being caught in fishing gear.
The primary threats blue whales currently face are vessel strikes and entanglements in fishing gear. NOAA Fisheries and its partners are dedicated to conserving and rebuilding blue whale populations worldwide. We use a variety of innovative techniques to study, protect, and rescue these endangered animals.
We engage our partners as we develop regulations and management plans that foster healthy fisheries and reduce the risk of entanglements, create whale-safe shipping practices, and reduce ocean noise.
Blue whales were significantly depleted by commercial whaling activities worldwide. The latest stock assessment reports of blue whales include data for various stocks, including areas of the North Pacific and western North Atlantic Oceans. Blue whales have a long body and generally slender shape. Their mottled blue-gray color appears light blue under water—hence their name, the blue whale.
The mottling pattern is variable and can be used to identify individuals. Antarctic blue whales are generally larger than other blue whale subspecies. For example, in the North Atlantic and North Pacific, blue whales can grow up to about 90 feet and are over , pounds, but in the Antarctic, they can reach up to about feet and weigh more than , pounds.
Like many other baleen whales, female blue whales are generally larger than males. Blue whales sometimes swim in small groups but are more often found alone or in pairs. They generally spend summers feeding in polar waters and undertake lengthy migrations towards the equatorial waters as winter arrives. Blue whales typically swim at about 5 miles an hour while they are feeding and traveling, but can accelerate to more than 20 miles an hour for short bursts.
They are among the loudest animals on the planet, emitting a series of pulses, groans, and moans, and it is thought that in the right oceanographic conditions, sounds emitted by blue whales can be heard by other whales up to 1, miles away.
Scientists think they use these vocalizations to communicate and—along with their excellent hearing—perhaps to sonar-navigate the dark ocean depths. When blue whales hunt for food, they filter feed by swimming toward large schools of krill with their mouth open and closing their mouths around the krill while inflating their throat pleats. Once closed, blue whales then push the trapped water out of their mouth with their tongue and use their baleen plates to keep the krill trapped inside.
Blue whales are found in all oceans except the Arctic. They generally migrate seasonally between summer feeding grounds and winter breeding grounds, but some evidence suggests that individuals in certain areas might not migrate at all. Information about distribution and movement varies with location, and migratory routes are not well known. In general, distribution is driven largely by food availability—they occur in waters where krill are concentrated.
Blue whales have been sighted in the waters off eastern Canada and in the shelf waters of the eastern United States. They likely feed during summer off the U. Blue whales with young calves are regularly observed in the Gulf of California Sea of Cortez from December through March. It is believed that this area is an important calving and nursing area for the species. In the northern Indian Ocean, there is a "resident" population. Blue whale sightings, strandings, and acoustic detections have been reported from the Gulf of Aden, Arabian Sea, and across the Bay of Bengal.
The migratory movements of these whales are largely unknown but may be driven by oceanographic changes associated with monsoons. In the Southern Hemisphere, Antarctic blue whales occur mainly in relatively high latitude waters south of the "Antarctic Convergence" and close to the ice edge in summer.
They generally migrate to middle and low latitudes in winter, although not all whales migrate each year. Pygmy blue whales Balaenoptera musculus brevicauda —a subspecies—are typically distributed north of the Antarctic Convergence and are most abundant in waters off Australia, Madagascar, and New Zealand. An unnamed subspecies of blue whale is found in the southeastern Pacific Ocean, particularly in the Chiloense Ecoregion, and migrates to lower latitude areas, including the Galapagos Islands and the eastern tropical Pacific.
Scientists can estimate the age of whales by counting the layers of wax-like earplugs collected from deceased animals. Scientists know little about the life history of the blue whale. The best available science suggests the gestation period is approximately 10 to 12 months. Weaning probably occurs at around 6 to 7 months on, or en route to, summer feeding areas. The age of sexual maturity is thought to be 5 to 15 years.
Most reproductive activity, including births and mating, takes place during the winter. The average calving interval is probably 2 to 3 years. Vessel strikes can injure or kill blue whales. These comments are now closed. We want your thoughts on COP How you can help garden wildlife this winter.
Should the number of dislikes on YouTube videos be hidden? Home Menu. Getty Images. As many as 55 blue whales have been spotted near the island of South Georgia. Why are blue whales so important? South Georgia is an island wildlife sanctuary, full of all kinds of animals from penguins to seals to albatrosses. Read More. The difference between these and blue whales is "easy to see," Loftsson said.
Conservationists disagreed however. Adam A. Pack, researcher and professor of biology at the University of Hawaii at Hilo , said the photos appeared to show a blue whale. Pack also noted the lack of a white lip, characteristic in fin whales, and the mottling on the whale's flank, an identifier that acts like fingerprints, as more evidence the animal in question was likely a blue whale. A member of the crew hoses down the whale.
The hooked dorsal fin is characteristic of blue whales. Authorities in Iceland will now conduct genetic testing to determine the whale's species, which may take months to complete.
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