Science Centres: Fisheries

Dunedin anglers are jubilant over the recovery of the salmon fishery in Otago Harbour, for which NIWA has supplied smolts and technical advice. ‘The increase has been tremendous, with 57 salmon weighed in to this year’s fishing competition, compared with only two last year’, says Mr Wayne Olsen, chairman of the Otago Branch of the New Zealand Salmon Anglers’ Association (NZSAA). This is only the tip of the iceberg, with possibly hundreds more salmon caught this season.

The harbour fishery is strictly ‘put and take’, originating from experimental releases by the Wattie/ICI salmon farm in 1983. After several years of poor returns, the NZSAA commissioned NIWA to review all historical release and return records from Otago Harbour. We used this review to identify and develop successful release programmes.

NIWA has contributed significantly to these release programmes. In the last three years, we’ve delivered 60 000 smolts from our Silverstream hatchery for direct release into the harbour. We’ve also provided ova and aquaculture advice to the local Sawyers Bay Hatchery, which has supplied the majority of smolts. The releases have been part-funded by salmon anglers, who have also marked 50 000 of the fish released. The marking programme will provide information on the return rates from different release strategies.