19 June 2007

Whale count on again in Cook Strait

Department of Conservation staff and former whalers are to team up again this winter to watch for whales in Cook Strait for research that assists efforts to protect whales in the South Pacific.

The annual DOC Cook Strait whale survey begins this Saturday, 23 June, and finishes on Sunday July 8. It is the fourth year of the two-week survey which is assessing recovery in humpback whale numbers since commercial whaling ended in New Zealand in 1963. The research counts numbers of humpbacks and other whales passing through Cook Strait and is timed to coincide with the peak period for whales migrating north to South Pacific breeding grounds.

DOC Wellington Conservancy marine specialist Nadine Gibbs, who leads the survey, said although the survey was finding indications of recovery in humpback numbers, humpback whale numbers in Cook Strait were well below what they once had been.

"Preliminary estimates suggest that the number of whales migrating annually through Cook Strait over the 2004-2006 period are only 29 per cent of the numbers seen in 1960, based on records from the Tory Channel whaling station. While this represents a significant recovery from 1963, when less than 20 were seen during the whole season, it appears that humpback whale numbers in Cook Strait remain highly depleted despite over 40 years of protection.

"By 1960, humpbacks had already been whaled for over 50 years in New Zealand so it is likely that the population then was already less than what it had been before whaling began."

Illegal Soviet whaling in the Antarctic and around New Zealand between 1960 and 1963 caused a dramatic drop in humpback numbers with around 25,000 humpbacks killed over two years.

The Cook Strait whale survey's findings could be used to assess any impacts from Japan's planned expansion of its Antarctic scientific whaling programme with the Japanese intending from this summer to take 50 humpbacks and 50 fin whales as well as doubling their annual catch of Antarctic minke whales to up to 935.

Last year, the survey counted 15 humpbacks. In the survey's first year, 2004, 47 humpbacks were recorded and another six whales were seen, some of which were identified as blue whales, the biggest creature on earth, with others possibly being sei whales. In 2005, 18 humpback whales were seen.

Ms Gibbs said the lower number of whales seen in the past two years was thought to be due to the whales migrating later than usual.

"This year, there are already quite a number reports of whales in New Zealand waters so it appears they have begun migrating north earlier than in the past two years. We may see more whales as a result, depending on when the migration peaks."

Former whalers - including Joe Heberley, Peter, Ron and Ted Perano and Tommy and Johnny Norton - are among volunteers who assist the survey. The ex-whalers spot for whales from the survey team's base on Arapawa Island near the entrance to Tory Channel.

Amy and Dan Engelhaupt of Marlborough's Dolphin Watch Ecotours also assist the survey and are providing the use of their boat Delphinius.

Members of the public can support the survey by reporting sightings of whales in the Cook Strait area or travelling up the coast from Kaikoura. Sightings can be reported to the survey team on 021 781 610 or DOC's Picton office on 03 520 3002. Information is sought on the date, time and place of whale sightings and the direction the whale or whales were travelling.

As well as counting whales, the survey also aims to find out more about whales passing through our waters. A boat is used to get near whales to endeavour to take photos and skin samples, using a biopsy dart rifle, which can be used to distinguish individual whales.

"We can learn more about where humpback whales seen in our waters migrate by checking our genetic samples and photographs against those obtained from across the South Pacific to see if any match," said Ms Gibbs.

"So far we have found three matches with whales photographed in the Cook Strait and also photographed in Hervey Bay, east coast Australia.

"Genetic analysis of skin samples taken so far suggests the humpbacks seen in Cook Strait are most closely related to humpbacks around New Caledonia."

ENDS

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