Abstract
The biological characteristics of warm-water fish species living in water bodies of the Arkhangelsk region are presented. Changes in size and mass parameters, age and sex structures and reproductive ability of the Severodvinsk sterlet in the temporal aspect were revealed. It has been established that it has good growth rates, a reserve in replenishing the spawning stock and a stable state of the natural reproduction system. The biological parameters of blue bream and rudd, rare species of fish that live in the lakes of the Kenozersky National Park, as well as a number of reservoirs in the Arkhangelsk region, were obtained. The biological characteristics of species that appeared in the river basin are considered. Northern Dvina as a result of self-dispersal - white-eye and asp, as well as the nutrition and feeding relationships of white-eye with native fish species. The attention of specialists to these alien fish species is due to the need to develop an environmental forecast for the development of the situation with their numbers in the context of ongoing global warming.