"The last thing that anyone on a ship wants to do is kill a whale," says Andy Mitchell, operations manager for vehicle and heavy cargo carrier Armacup.
Reducing speed from the customary 15 knots to a desired 9 or 10 knots is expected to greatly improve survival chances if whales are struck. The move will add up to 1 hours to transit times, time which can't be made up on short coastal hauls such as Auckland-Tauranga. Mr Mitchell said running ships at slower than their design speed also meant more work for the crew and possible additional costs. "But if we can take some measures to reduce the risk to these whales then we are keen to do so."
Bryde's whales are thought to congregate in the gulf because of plankton, krill and small fish. But habits which include lurking just below the surface and spending long periods resting at night make them vulnerable to commercial and cruise ship traffic.
No more than 200 are thought to be left in NZ waters and records suggest at least two a year are dying due to ship strike. Ports of Auckland chief executive Tony Gibson said the protocol stemmed from a collaborative effort involving shipping companies, university researchers, the Department of Conservation, Hauraki Gulf Forum and Environmental Defence Society. He praised Dr Constantine's pragmatic approach for the eventual agreement.
The port company is also contributing $30,000 to a year-long project using aerial surveys to count and map the distribution of whales and other marine mammals, which may lead to further changes in shipping routes. High-tech warning systems are also being investigated.
Gulf forum chairman John Tredidga congratulated the industry and port company.
"There is good scientific evidence that 10 knots is a safe travelling speed around whales."