The use of new fish species in polyculture in fish farming

Abstract

Increasing the potential productivity of biocenoses and their resistance to abiotic stresses, as well as increasing the productive and environmental functions of ecosystems, is also an urgent task. The main direction of development of the strategy of even carp farms is considered to be the presence of a much larger number of additional fish. In modern conditions, the most important means of increasing the fish productivity of ponds and natural reservoirs can be considered the expansion of the range of bred fish, taking into account the available feed base and the level of biotechnics. The traditional set of fish, which is recommended to be included in the polyculture of the north-western regions for the fullest use of the feed base, is represented by the following fish: planktophages (peled), benthophages (chir, pyjian, carp, etc.), predators (pike perch, pike, trout, etc.), phyto-, zooplanktophages (white amur and motley carp), in some cases herbivorous (white cupid). Depending on the specific conditions, these or other objects are preferable. For example, in the fertilized lakes of the north-west, the main species feeding in pelagial is considered to be pelage, but it is better that this zone is mastered by silver carp, which is also a filter of phytoplankton and detritus (they make up 80–90% of the food lump). It is better than peled to master the nectobentos of the Chudsky whitefish, muksun and hybrids of peled with chir. Along with whitefish, it is advisable to grow carp or crucian carp in shallow lakes. Depending on the composition of the native ichthyofauna, which plays an essential role in the biocenosis, a polyculture may consist of a less familiar set of fish. Reservoirs built on peat workings of low-lying swamps are quite suitable for growing fish in polyculture: carp, tench, white amur, mottled and white carp, golden and silver carp, pike, walleye and even under particularly favorable conditions — trout and whitefish.