Further protection measures are needed to allow
Hector's dolphin populations to recover.

Recently announced protection measures will slow Hector's dolphin decline, according to a new study released on June 29.

However, the study also found that further protection would be needed to halt the decline in Hector's dolphin numbers, and allow population recovery.

The paper, Effectiveness of new protection measures for Hector's dolphin, by Otago University Associate Professor of Zoology Elisabeth Slooten and Associate Professor of Marine Science Steve Dawson was reviewed by the Scientific Committee at the International Whaling Commission (IWC).

The scientists analysed the impact of the new protection measures announced last month by Fisheries Minister Jim Anderton. The meeting of the IWC Scientific Committee was the first opportunity for peer review of the research, just a few weeks after the Minister's decision. More than 200 scientists from around the world attended the meeting.

The new protection measures include regional bans on set netting, trawling and drift netting in some coastal waters, increased monitoring of commercial fishing vessels and the establishment of four new marine mammal sanctuaries.

The current population of Hector's dolphins is less than 8000 individuals, down from more than 30,000 in 1970.

Without the new protections, the population was projected to decline to just over 5000 individuals by 2050. With the protections, the population is projected to decline much more slowly. As a result, the population in 2050 would be just over 7000, a decline of about 600 individuals compared to current population levels.

Full protection from bycatch in gillnets and trawl fisheries in the coastal waters where the dolphins live would help the population almost double by 2050, recovering to more than 15,000 individuals or about half of the original population size.

"The new protection measures are a major step forward," says Associate Professor Slooten.

"They're not enough, yet, but they're a step in the right direction. Our research shows they'll slow the slide towards extinction. But more will need to be done to achieve population recovery.

"Current population size of Hector's dolphins is only about a quarter of their original population size. New Zealand legislation requires recovery to non-threatened status within 20 years. Legislation in the USA requires that fisheries bycatch not slow down the rate of recovery by more than 10 per cent. The new protection measures do not yet meet either of these criteria," says Associate Professor Slooten.

Hector's dolphins are found only in New Zealand waters and are among the world's rarest dolphins. The World Conservation Union, and the Department of Conservation, classify them as 'Endangered' – meaning they face a high risk of extinction in the near future.

Associate Professor Slooten says fishing methods other than gillnetting could be just as economic without resulting in by-catch of dolphins and other species such as penguins and shags. In the long term, a change to more selective, sustainable fishing methods would also benefit fish stocks and therefore the fishing industry.

The paper was discussed at the Scientific Committee of the International Whaling Commission conference in Chile, which ended on Friday (June 27).

The Scientific Committee concurred that the new protection measures are a major step forward but noted that 'additional measures are likely to be required to ensure recovery of the species.'