Biology and fishery features of bream (Abramis brama L.) in some lakes оf Karelian Republic

Fish resources of inland waters of Karelia are used extremely unevenly. In Karelian lakes and reservoirs, valuable fish species (lake salmon, lake trout, palia, whitefish, and pike-perch) are intensively harvested. At the same time the reserves of bream, roach, perch, ruff and other small-particle fish are almost everywhere underused. The state of the bream population in a number of fishing reservoirs of the Republic of Karelia (Lake Onego, Ladoga, Syamozero, Vygozero and Vodlozero reservoirs) is estimated for the first time in the framework of the forecast topics. The research tasks included: a study of the size-weight, the age composition and the age of the bream puberty; calculation of its abundance and biomass at the present stage; development of the basic strategy of its rational use. The calculations of the bream abundance and biomass are given. The estimation is necessary for the objective solution in fishery regulations and forecasting of the bream catch at this stage. From the data obtained, it was clarified that bream stocks are currently exploited mainly at the expense of its mature individuals within the limits of permissible values. But, despite this, it is necessary to strictly regulate and control the intensity of its fishing, taking into account that this fishery object refers to the type of fish with a long life cycle, which requires special attention when changing the intensity of its fishing.