Fisheries Minister Phil Heatley has approved new catch limits for southern blue whiting.
The changes are estimated to increase export earnings from the fishery by $4 million, to $30 million per year.
Mr Heatley says stocks of southern blue whiting around the Campbell Islands have grown significantly, prompting him to increase the allowable annual catch by 30%, to 30,000 tonnes.
But he says stocks are declining around the Bounty Islands, so the annual catch limit there is to be more than halved, from 15,000 to 7000 tonnes.
Mr Heatley says a second cut to the Bounty Islands catch limit will be made next year.
The new limits come into effect from 1 April.
