Pilot whale

The Pilot Whale is one of two species of cetacean in the genus Globicephala. The genus is part of the oceanic dolphin family (Delphinidae) although their behavior is closer to that of the larger whales. The two species are the Long-finned Pilot Whale and the Short-finned Pilot Whale. The two are not readily distinguished at sea and are typically just known simply as Pilot Whales or Calderón in Spanish. They and other large members of the dolphin family are also known as blackfish.

Physical description

Pilot Whales are jet black or a very dark grey color. The dorsal fin is set forward on the back and sweeps back. The body is elongated but stocky in the tail fin.

The differences in appearance of the two species are quite subtle and where their distributions overlap it is generally not possible to tell the species apart at sea. When the whales are studied on the land they can be distinguished by the length of flipper, the number of teeth and the shape of the skull: the Short-finned has a more bulging head particularly in older males; the Long-finned is squarer, and the forehead is more likely to overhang the mouth.

Birth weight is about 132 pounds (60 kg). Adult weight varies from 1 to 3 tons (1,000 to 3,000 kg). Average length is 13 to 22 ft (4-7 meters). Life span is about 45 years in males and 60 years in females for both species.

Both species live in groups of about 10 to 30 in number. They are quite active and will frequently lob tail, spy hop and approach boats.

Pilot Whales feed predominantly on squid. Tuna and Pilot Whales are frequently found in the same area. This is probably because they share a common diet (squid) rather than that the Pilot Whale feeds on tuna. Pilot Whales are more susceptible than most species to beaching. It is possible that squid spawning close to shore attract Pilot Whales and cause them to beach.

Population and distribution

Pilot Whales are amongst the most common and widely distributed of the marine mammals in the cetacean order.

The Long-finned species prefers slightly cooler waters than the Short-finned and is divided into two populations. The larger group is found in a circumpolar band in the Southern Ocean running from approximately 20° S to 65° S. It may be sighted off the coasts of Chile, Argentina, South Africa, Australia and New Zealand. There are estimated to be in excess of 200,000 individuals in this group. The second population is much smaller and inhabits the North Atlantic Ocean, in a band that runs from South Carolina in the United States across to the Azores and Morocco and its southern edge and from Newfoundland to Greenland, Iceland and northern Norway at is northern. It is also present in the western half of the Mediterranean Sea.

The Short-finned species is more populous. It is found in temperate and tropical waters of the Indian, Atlantic and Pacific Oceans. Its population overlaps slightly with the Long-finned Species in the western Atlantic. There are 150,000 individuals in the eastern tropical Pacific Ocean. There are estimated to be more than 30,000 animals in the western Pacific, off the coast of Japan.

Both species prefer deep water.

Pilot whale

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