The natural reproduction potential of various economically valuable species of fish deceases in the eco-systems of natural waters due to negative influence of human activity and as well as due to short-term and long-term changes of environmental factors. Changes take place in the structure of the fish fauna and fish resources tent to decrease considerably. In order to avert these negative processes and to ensure the sustainability of fish resources in state water bodies that are available to general public, the national fish reproduction program and its guidelines are developed in the country.
The aim of the guidelines is to ensure scientifically based sustainability and variety of valuable fish resources in water bodies that are available to general public and to minimise loss caused by anthropogenic influence as well as to foster the possibilities of the development of sustainable fishing and angling in Latvia.
By ensuring the fulfilment of the guidelines, every year fish farms of the institute release in the reservoirs of rivers Gauja, Venta and other small rivers at least 5.76 million, and to compensate for the loss caused by the operation of Daugava HES cascade – in the reservoir of the river Daugava at least 6.37 million fries and maggots of various species of fish.
The main species of fish that within the framework of fish reproduction program are cultivated in fish farm “Tome” and its branches “Dole”, “Kārļi” with hatcheries “Brasla” and “Pelči” are salmon, sea trout, zander, vimba, whitefish, brown trout, pike, freshwater-cod, and river lamprey.