21 January 2003
So little is known about the type of whale stranded on Waiheke Island that scientists cannot even say for sure whether it is rare or not.
A 4m female Gray's beaked whale, which stranded and died at West Onetangi Beach on Sunday, was yesterday towed away for burial by Department of Conservation (DOC) staff.
In spite of bleeding from the stranding and the presence of round nips on its body from cookie cutter sharks, the whale was in good condition, leading DOC staff to consider whether it had died after eating some plastic.
Using echo location, a whale can mistake a plastic bag for a squid which the beaked whales are known to feed on. This can lead to starvation as the whale cannot then feed properly.
"They can suck in a plastic bag and think it's a squid and that's the end of that," said DOC biodiversity programme manager Simon Mowbray.
Mr Mowbray said the whale did not show signs of starvation and the cause of death may never be established.
An autopsy will be carried out on the whale.
Marine mammal biologist Rochelle Constantine, of the University of Auckland School of Biological Sciences molecular ecology and evolution laboratory, said about 15 of 21 species of Southern Hemisphere beaked whales were found in New Zealand waters.
While strandings of beaked whales were not uncommon in New Zealand, so little was known about the animals that it was hard to say whether they were rare.
But Dr Constantine said if the whales were fairly common there would have been more sightings.
"Until we know more about these whales we can only assume there aren't many of them."
The whales live in deep water and individually or in small groups.
"They are enigmatic. They really are an unknown quantity. We assume we would see more if they were common and if they were in abundance, but honestly I don't think they are."
A research team has collected genetic samples from the whale for a university database established to increase understanding of the whales.