Whales - Species | Ginkgo Toothed Beaked Whale

Ginkgo-toothed Beaked Whale - Mesoplodon ginkgodens

The Ginkgo-Toothed Beaked Whale, is found in the North Pacific from Japan to California, and has also been sighted in the Indian Ocean. They have been found stranded off the coasts of Japan, California, Mexico, Taiwan, Indonesia and Sri Lanka. Because of its rare sightings, it is thought to prefer warm, offshore open waters. It is a poorly known species of whale, even for the beaked type, with the major difference being the lack of scarring on the male body. It was named for the unusual shape of its two teeth, being similarly shaped to the leaves of the oriental Ginkgo tree, with a central point and nearly symmetrical curving sides; hence the common name for this species. The dorsal fin is small, often hooked, and positioned two-thirds of the distance from the beak to the tail.

This species of whale is more robust than most mesoplodonts, but is fairly typical in appearance. It has a moderately long beak, but unlike other species, its teeth do not arch over its rostrum. The colour of the male is dark grey with light patches on the beak and around the head, but they also have small white spots on the bottom of the tail. Females are usually a lighter grey with some countershading. Newborns measure approximately 2.4 meters long at birth, with adults reaching 4.9 meters at full term.

Sightings of the Ginkgo-Toothed Beaked Whale are rare due to their deep-ocean distribution, elusive behaviour and possible low numbers. Therefore, their behaviour and breeding habits are fairly unknown. It seems they are unobtrusive and found in small groups. Their lack of scarring suggests little or no aggression between males. Its diet also seems to be unknown, however, it is likely to feed on squid and deepwater fishes, and possibly crustaceans found on the sea floor. But due to their lack of functional teeth, they presumably capture most of their prey by suction.

This species may be confused with the Andrews' Beaked Whale, however the beak is longer and the exposed portion of the teeth is much smaller. But while it is difficult to distinguish from other species at sea, its darker colour, the apparent lack of heavy scarring in adult males, and the small portion of the tooth emergent from the gum tissue may help to distinguish Ginkgo-toothed Beaked Whales. However, no live adult Ginkgo-toothed Beaked Whales have yet been examined, so these differences are speculative.