The main task of the Branch of Hatchery “Kārļi” – Hatchery “Brasla” is the renewal of the resources of sea trout in the basin of the river Gauja. The hatchery breeds and releases in the basin of the river Gauja about 200 000 sea trout smolts and fries annually. The hatchery breeds also steelhead trout fries and lamprey maggots.