Pygmy sperm whale
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Kogia breviceps

Names

POR : Cachalote Pigmeu - ITA : Kogia di Blainville - SPAIN : Cachalote pigmeo - GB : Pygmy sperm whale - GER : Zwergpottwal - JAP : Komakko kujira

Biology

Adults' average size is 3 m, but they can reach a maximum of 4 m in length. Weight varies between 320 and 400 kg. The lower jaw is very short and narrow and generally has 12 to 16 pairs of thin teeth. Similarly to the sperm whales, the upper jaw does not have teeth. Coloration is, in general, dark. The body is robust and the adult's head resembles that of the sperm whale (Physeter macrocephalus). The only blowhole is on top of the head, left of the midline. On each side of the head there are crescent or bracket-shaped marks that resemble the gill slits of fish. Contrary to the sperm whale, the dorsal fin of this species is falciform. Newborns measure about 1.2 m and weigh about 55 kg. Gestation lasts 9 to 11 months, and lactation takes about 1 year. This species feeds mainly on cephalopods (octopus and squid), but sometimes they prey on small fish, crabs and some invertebrates. This species can emit echolocation sounds.

Observation

Field observations of this species are rare. This animal is secluded and lives in deep waters far from shore. Apparently, they are not gregarious and they live alone or in small groups of 2 to 6 individuals. Besides this, they can be easily confused with their " cousins ", the Kogia simus. One specimen of Kogia was found stranded alive on the southern coast of the island of Faial in June 1996. In the ocean it is not possible to differentiate the two species. They swim at an average speed of 4 knots, but are probably capable of reaching much higher speeds. To dive, they first sink and disappear afterwards. They can reach depths of up to 300 m. They have frequently been observed moving away from vessels. They sometimes jump out of the water. When surprised, they become frightened and may defecate, issuing a cloud of reddish brown before diving.

Cetaceans in the Azores