orcas-Johnson straits,British Columbia
1 m) long and weighing upward of 10,000 pounds.[14]
[edit] Distribution
To travel quickly, Orcas leap out of the water when swimming—a behavior known as porpoising.
Orcas are found in all oceans and most seas, including (unusually for cetaceans) the Mediterranean and Arabian Seas. However, they prefer cooler temperate and polar regions. Although sometimes spotted in deep water, coastal areas are generally preferred to pelagic environments.
The Orca is particularly highly concentrated in the northeast Pacific Basin, where Canada curves into Alaska, off the coast of Iceland and off the coast of northern Norway. They are regularly sighted in Antarctic waters right up to the ice-pack and are believed to venture under the pack and survive breathing in air pockets like the beluga does. In the Arctic, however, the species is rarely seen in winter, as it does not approach the ice pack. It does visit these waters during summer.
Information for off-shore regions and tropical waters is more scarce, but widespread, if not frequent, sightings indicate that the Orca can survive in most water temperatures. Sightings are rare in Indonesian and Philippine waters. No estimate for the total worldwide population exists. Local estimates include 70,000–80,000 in the Antarctic, 8,000 in the tropical Pacific (although tropical waters are not the Orca's preferred environment, the sheer size of this area—19 million square kilometres—means there are thousands of Orcas), up to 2,000 off Japan, 1,500 off the cooler northeast Pacific and 1,500 off Norway. Adding very rough estimates for unsurveyed areas, the total population could be around 100,000.
With the rapid decline of Arctic sea ice in the Hudson Strait, the range of Orcas has now extended into the far northern waters of Canada. Through the 1990s, Orcas were sighted in western Hudson Bay at a rate of six per decade; sightings rose to more than 30 between 2001–2006.[15]
The migration patterns of Orcas are poorly understood. Each summer, the same resident Orcas appear off the coasts of British Columbia and Washington State. After decades of research, it is still unknown where these animals go for the rest of the year.
Scientists spotted a white killer whale off Alaska on February 23, 2008.[16]
[edit] Distribution
To travel quickly, Orcas leap out of the water when swimming—a behavior known as porpoising.
Orcas are found in all oceans and most seas, including (unusually for cetaceans) the Mediterranean and Arabian Seas. However, they prefer cooler temperate and polar regions. Although sometimes spotted in deep water, coastal areas are generally preferred to pelagic environments.
The Orca is particularly highly concentrated in the northeast Pacific Basin, where Canada curves into Alaska, off the coast of Iceland and off the coast of northern Norway. They are regularly sighted in Antarctic waters right up to the ice-pack and are believed to venture under the pack and survive breathing in air pockets like the beluga does. In the Arctic, however, the species is rarely seen in winter, as it does not approach the ice pack. It does visit these waters during summer.
Information for off-shore regions and tropical waters is more scarce, but widespread, if not frequent, sightings indicate that the Orca can survive in most water temperatures. Sightings are rare in Indonesian and Philippine waters. No estimate for the total worldwide population exists. Local estimates include 70,000–80,000 in the Antarctic, 8,000 in the tropical Pacific (although tropical waters are not the Orca's preferred environment, the sheer size of this area—19 million square kilometres—means there are thousands of Orcas), up to 2,000 off Japan, 1,500 off the cooler northeast Pacific and 1,500 off Norway. Adding very rough estimates for unsurveyed areas, the total population could be around 100,000.
With the rapid decline of Arctic sea ice in the Hudson Strait, the range of Orcas has now extended into the far northern waters of Canada. Through the 1990s, Orcas were sighted in western Hudson Bay at a rate of six per decade; sightings rose to more than 30 between 2001–2006.[15]
The migration patterns of Orcas are poorly understood. Each summer, the same resident Orcas appear off the coasts of British Columbia and Washington State. After decades of research, it is still unknown where these animals go for the rest of the year.
Scientists spotted a white killer whale off Alaska on February 23, 2008.[16]
posted by Glenn Rye | 9:17 AM
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