A new method of releasing fish into Rotorua lakes aims to increase the survival rate of young trout.
Fish & Game NZ officers have changed the way they release fish into some lakes in the spring and autumn and are trialling a new method of staggering the release of trout.
In spring, thousands of yearling trout are released into most of the Rotorua lakes.
Fish & Game officer Matt Osborne said new information from a monthly tagged fish trial in Lake Tarawera and a PhD study on trout and smelt in Lake Rotoiti showed a wider spread to the timing of the releases should provide better results.
"In the past, we released all of the spring fish in one hit in September, but this recent research indicates that we're likely to get better survival and growth of the juvenile trout if they're let go in more batches over a wider timeframe."
He said winter was a poor time for growth in the lakes so Fish & Game NZ were safeguarding the hatchery's investment by starting the autumn releases earlier and finishing the spring releases later to avoid the lower winter food supplies. The spring releases would now be carried out through September, October, November and December and autumn releases would begin in February and continue until May.
"This staggered programme is being tested on Lakes Tarawera, Rotoiti and Okataina where Fish & Game officers see the best growth. This should provide good fish for the boating anglers during the summer and also good shoreline fishing for the winter anglers," Mr Osborne said.
He said in addition to the larger lakes, Fish & Game NZ also released trout into a number of smaller lakes across the region. The latest release was 700 rainbow and brown trout into Lake McLaren and the Ruahihi Canal in the lower Kaimais.