Whales

Gray’s Beaked Whale - Mesoplodon grayi

The Gray's Beaked Whale, also known as Haast's Beaked Whale, the Scamperdown Whale, or the Southern beaked whale is one better known members of the Mesoplodon genus. This species was described from the remains of animals found at a mass stranding involving approximately 28 whales in the Chatham Islands off New Zealand in 1874. It was named after the former Director of the British Museum, John E. Gray, who had died the previous year. It is noted for being the only beaked whale, other than the Shepherd’s Beaked Whale, that has numerous teeth.

The Gray's Beaked Whale is a fairly slender member of the genus, with females reaching at least 5.3 meters, males being 5.7 meters and weighing around 1.1 tonnes. They are believed to measure around 2.4 meters when born. Its melon bulges towards the blowhole and slopes down towards the beak, which in itself is very long and pointed. Both sexes have 17-22 small teeth at the back of their mouth, which barely protrude past their gums. Males, however, have two small, triangular teeth halfway down the mouth. In males, there is a single mandibular tooth positioned near the middle of each side of the jaw. In adult males, these teeth tilt forward slightly and are large and triangular; they may grow up to 10cm wide, although approximately 6cm wide is more common. They are also dark bluish-grey in colour on top and lighter underneath, with both genders having a white beak. Females are lighter on top than males with additional white markings near their genitals. Scars are typically present on the bodies of males probably inflicted by other males. The dorsal fin is hooked and rather pointed. As the whale surfaces to breathe, the long white beak protrudes from the water.

The diet of this species is mainly unknown, but presumably feeds on deep-sea fish and squid, and possibly crustaceans and echinoderms found on the sea floor. But because they lack functional teeth, they presumably capture most of their prey by suction.

Gray's Beaked Whales occur mainly in the Southern Hemisphere, especially in cold temperate waters. Gray's Beaked Whale is the second-most commonly stranded beaked whales in Australia, and the most common beaked whale to strand in New Zealand with up to 28 individuals being reported. Sightings and strandings suggest that the species is common in the Indian Ocean, south and east of Madagascar, as well as off South America, the Falkland Islands, New Zealand and Western Australia. Strangely enough, one specimen has been found stranded off the Netherlands, on a different Hemisphere and several thousand miles away from all other strandings. Mostly the Gray’s Beaked Whale is found in aggregations of two or three, but larger pods of up to 20 individuals have also been sighted. No population estimates exist, but they are believed to be rather common.