An endangered dolphin has been satellite-tracked far outside a marine sanctuary but critics of the controversial project say that is nothing new.
An initial report on the satellite-tracking trial of three endangered Hector's dolphins around Banks Peninsula near Christchurch shows the animals make forays up to 20km outside afour-nautical-mile-wide protection zone.
"The excursions outside did surprise me a little bit but the data is very speculative at this stage," said Dr Gregory Stone, vice-president of Boston-based New England Aquarium which is providing the technology for the trial.
Auckland Department of Conservation head Rob McCallum, who is a supporter of the trial, said more was being learned in a few months about the dolphin's behaviour than had been in the past 20 years.
"The dolphins are going a lot further than anyone found before, well outside the area currently set aside for them."
Dr Stone said the tagging results also confirmed what scientists knew - that the dolphins also stuck close to shore.
"We confirmed their distribution generally close to shore but we did that in just a few months rather than a few decades," he said.
DoC is running the satellite tagging trial to find out if the technology could be used on Hector's dolphin's close relation, the North Island Maui's dolphin.
While Hector's are thought to number between 3000 to 4000, Maui's are estimated at between 80 and 150 animals, making them one of the rarest dolphins in the world.
Amateur and commercial fish nets are banned within the Banks Peninsula sanctuary and along a stretch of the North Island coast to prevent the dolphins drowning in them.
The animals are also vulnerable to trawling further offshore.
Marine biologist Dr Liz Slooten of Otago University, who has studied the dolphins since 1984 and is one of New Zealand's top marine mammal researchers, said the initial satellite data didn't reveal anything not already known.
"So far the information that's come out shows there is nothing new there," she said.
Dr Slooten, conservation group Forest and Bird and the Green Party all opposed satellite tagging, saying it could harm the dolphins and the data gained would have questionable value.
The animals were lifted into a boat and matchbox-sized locators attached to their fins.
