New status for endangered Hector's dolphin
New status for endangered Hector's dolphin
The critically endangered North Island Hector's dolphin has for the first time been recognised as genetically different from its South Island relative, Conservation Minister Chris Carter announced today.
Scientists from the Department of Conservation and Auckland University's School of Biological Sciences have found that the North Island dolphins differ from the South Island population in both their physical and genetic characteristics.
While dolphins from the two populations look very similar, there are consistent differences in their body form, skeletal features, and DNA.
The North Island dolphin have been classified as a separate subspecies and given a new official name, Cephalorhynchus hectori maui.
The name is derived from the legendary Maori fisher Maui, who fished up the North Island. The common-use name for the northern subspecies will be Maui's dolphin, while the southern population will continue to be called Hector's dolphin.
Mr Carter said the classification recognised the unique status of the North Island population.
"These are beautiful creatures and there aren't many of them left. The best data we have available suggests there may be as few as 100 to 150 still alive, making them as rare as the kakapo."
The North Island dolphins are found only on the north-west coast of the North Island between New Plymouth and Dargaville, while the South Island Hector's dolphins, which number just over 7000, are found almost all around the southern coasts.
The Journal of the Royal Society of New Zealand is publishing a scientific paper about the subspecies on its website this week.
The new subspecies status firms up the North Island population's status as critically endangered as classified by the International Union for the Conservation of Nature (IUCN). The South Island population remains classified as endangered.
Facts about Hector's dolphins:
* These
are one of the world's smallest marine dolphins and are
found only in New Zealand waters.
* They are mostly
seen close to shore and in summer they frequent shallow
waters less than 20 metres in depth.
* They are
characterised by their distinctive grey, white and black
markings, short snout and well-rounded black dorsal
fin.
* They live for up to 20 years. Females grow to 1.7
metres long; males are slightly smaller.
* Like other
dolphins, they use echolocation to find their food. They
send out high frequency 'clicks' that bounce off surrounding
objects and fish, giving the dolphins a detailed picture of
their surroundings.