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Joe Heberley's work history will not endear him to most New Zealanders. The Marlborough veteran fisherman used to make a living hunting whales - something New Zealand now leads the fight against on the world stage.
From today, Mr Heberley will again have the mighty mammals in his sights - but for reasons in keeping with public opinion.
He and other former whalers are joining the Department of Conservation (DoC) in research to help protect the whales.
"The old whalers around here now are probably the biggest conservationists you can get, because we knew what happened," he says.
"The 150-odd whales New Zealand were taking a year ... that was just a pittance compared with what the Japanese and Russians took."
Mr Heberley thinks his whaling days, 40-plus years ago, put him in a unique position to understand whale populations.
"I was lucky enough to have four years whaling [in Cook Strait] straight out of school. Dad finished here and semi-retired and then he got offered a job to go up to the Great Barrier [Island], so I left school and went with him and I was gunning up there - that was shooting the whales."
He returned in about 1962 to whaling in the Cook Strait prior to the end of the practice in New Zealand in 1964.
Mr Heberley says he could not bring himself to hunt a whale today.
"It was big business in those days. Things have changed rapidly. And we know now we couldn't have carried on the way we were."
He and the other former whalers will be based in a hut on Arapawa Island, at the entrance to Tory Channel, from today to record humpback whale numbers for DoC. They will work unpaid from dawn to dusk for two weeks.
"This is the time of year when the humpbacks are migrating north, so we are just trying to get a count of them and do DNA samples [with dart rifles]."
Mr Heberley sees it as a chance to make a positive difference.
"The humpbacks are showing signs of recovery if the Japanese would leave them alone. They are a wonderful creature. It makes the blood boil when you spot one - just like old times."
DoC marine specialist Nadine Gibbs said despite the indication of a recovery, the 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 2004-06 period are only 29 per cent of the numbers seen in 1960."
The Cook Strait whale survey findings may be used to assess the impact of Japan's planned expansion of its Antarctic scientific whaling programme.
"This year, there are already quite a number reports of whales in New Zealand waters," Ms Gibbs said, "so it appears they have begun migrating north earlier than in the past two years."