Fewer Hector's dolphins are being caught in set nets
following a change in fishing rules several years ago, but
the population around the Otago coast remains low, a
University of Otago professor says.
A study by a university master's student and staff in 2011
estimated the population of the mammal to be about 42 from
Taieri Mouth to Oamaru.
Dolphin specialist Prof Steve Dawson, of the Otago marine
science department, said there had been no noticeable
population change since set nets were banned within 4
nautical miles of most of the South Island's east coast in
‘‘I wouldn't expect that [population] to have changed
much.‘‘For a start, those animals don't move around very much
- they're very much homebodies.
‘‘They breed about 2% per year at the maximum. So, if there
were 50 animals one year, there might be 51 the next year.''
Prof Dawson reiterated his call to ban set nets not only off
the coast, but also in harbours.
It did not make sense that there were limits on fishing
catches, but not on how many dolphins, penguins or seabirds
were caught as bycatch, he said.
Department of Conservation biodiversity ranger Jim Fyfe said
Hector's dolphins were endangered in New Zealand.
A subspecies, the Maui dolphin, was critically endangered,
and fewer than 100 remained around New Zealand, he said.
However, the set net changes had an effect, he said.