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Killer Whales

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Killer whales

Killer whales are found in all the world's oceans and throughout Southeast Alaska. Also known as orcas, killer whales are the fastest marine mammal and one of the fastest creatures in the sea, capable of speeds of up to 35 mph. Killer whales are acrobatic and will breach like humpbacks, spy hop, tail lob and slap their big pectoral flippers against the water.

Killer whales are the largest member of the dolphin family. Like other dolphins and porpoises, they are capable of navigating and hunting under water in complete darkness using sound and echolocation, much like sonar. Killer whales emit a series of clicking sounds which they direct forward in a focused beam (the squeaks and squeals killer whales make when vocalizing are different from their echolocation clicks). They listen for the echo of the sound bouncing off objects in their surroundings and can judge the size, distance and speed of swimming prey.

Most killer whales in Southeast Alaska waters belong to two groups, resident and transient. The two types are genetically different and have distinct foraging and social behaviors and dietary specialization. In addition to being much quieter than resident killer whales, the pattern and type of sounds that transients make are different from residents. A third group, known as "offshores," has a broad distribution down the West Coast from the Gulf of Alaska to California. As the name implies, they range much farther offshore.

Transients feed on marine mammals. Because marine mammals can hear echolocation sounds and whale vocalizations, transient killer whales tend to be very quiet and usually vocalize only after making a kill. The West Coast Transient Stock is estimated to be about 325 individuals and ranges along the West Coast from Southeast Alaska to California.

Resident killer whales feed on fish, primarily salmon. They are very vocal and have sophisticated calls. The resident population in Southeast consists of about 200 individuals in 16 pods, ranging from the central coast of British Columbia to Southeast Alaska.

Pods are small "packs" of whales, which are usually family members. Young whales, known as calves, can often be seen in a pod of killer whales. Members of resident pods tend to be very stable, while members of transient pods are more dynamic. Transient pods tend to number three to seven animals. Resident pods often number more than 10 animals and can be as large as 50 animals.

What to look for: Killer whales are 25 to 30 feet in length. They will often cruise at the surface, spouting every few seconds as they swim. The black back, white eye patch, and striking triangular dorsal fin are characteristics of the killer whale. (The dorsal fin is the large fin on the center of a fish or marine mammal's back.) The dorsal fin of the male is much taller than the females and can be six or seven feet high. To identify individual whales, biologists use identifying characteristics (size, shape and distinctive scars or marks) of the dorsal fin and the gray "saddle patch" on the back behind the dorsal fin.

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