Massey University pathologists are waiting for lab tests to confirm the cause of death of a female Hector's dolphin.
An autopsy was carried out on the dolphin by Massey marine mammal pathologist Wendi Roe at the weekend, but exactly how it died remains a mystery.
"We still need to do quite a bit more lab work on this particular one to work out the cause of death, but at this stage it doesn't look like she was caught in a fishing net," Dr Roe said.
The dolphin was found late last week at Hokitika. Hector's dolphins are classed by the Department of Conservation as "nationally vulnerable", with a population of about 7400.
They are closely related to the Maui's dolphin, the world's most endangered dolphin species.
"[Massey] are contracted by DOC to do post mortems on all Hector's and Maui's dolphins that are found dead. I've been doing post mortems on these dolphins for about six years now, along with work on other marine mammals, including sea lions," Dr Roe said.
Massey had been sent 75 Hector's dolphins in the past five years, and four Maui's Dolphins she said.
There was a lot that could be learnt from the autopsies.
"We can get a lot of information from each post mortem that is done, and we collect samples, not just for cause of death analysis, but also for ageing the animals, looking at their genetics, their diet, toxin levels and so on. Lots of this work is done in collaboration with other universities around New Zealand."
Hector's dolphins are found only in New Zealand's waters. One of the smallest dolphins species in the world, Hector's dolphins grow to no more than 1.5 metres in length.
They are a distinctive grey colour, with black and white markings and a round dorsal fin, and are typically found in shallow waters around the South Island.
- © Fairfax NZ News
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