Concern about future of bluefin tuna

Press, 5 September 1983, Page 25

Concern about future of bluefin tuna

Wellington reporter

International concern is growing about the overfishing of southern bluefin tuna, including off the West Coast of New Zealand.

Bluefin have been heavily fished by Australia and Japan since the late 19505, and more recently by New Zealand too. The three countries are now trying to reach agreement on an international management plan, according to the assistant director of the Fisheries Research Division of the Ministry of Agriculture and Fisheries, Dr R. Allen. The 1982 catch was estim-

ated to be about 40,000 tonnes. This comprised 22,000 tonnes taken by Japan, 18,000 tonnes by Australia, and 250 tonnes by New Zealand.

However, the Japanese catch included 2800 tonnes taken in New Zealand’s exclusive economic zone, only about half the average taken there over the last 10 years.

Dr Allen said there was concern that if the present pattern of catching about 20,000 tonnes of both large and small fish persisted, the adult stock size would start to decline again by next year.

Any further decreases in size would threaten its

capacity to reproduce. Scientists wanted to ensure that stock size was not reduced, and to do this the catch had to be reduced, particularly of small fish. One way to do this would be to reduce the catch of small fish to 10,000 tonnes and allow 25,000 tonnes of large fish to be taken, Dr Allen said.

Although this would cause a slight decrease in adult stock size, this was expected to be temporary. Dr Allen said representatives of the three countries would meet in Australia later this year to try to reach agreement on a management plan.