Biotechnical indicators of red-clawed crayfish commercial cultivation in pond aquaculture in the conditions of the South of Russia

Abstract

Work was carried out on commercial cultivation of the australian red-clawed crayfish Cherax quadricarinatus in the pond aquaculture of the Astrakhan region in the summer-autumn period of 2021 and 2022. During the exper-iment, young crayfish were studied, formed in 5 groups in accordance with the initial average weight of 0.17, 0.18, 1.8, 5.1 and 7.8 g and cultivated in ponds with an area of 0.1 hectares each. The duration of cultivation was 62-99 days, depending on the groups under consideration. During the work, the main size and mass characteristics of cancers in each group were determined, linear growth, weight gain, bio-mass, survival, overall cancer productivity, and the yield of marketable products were calculated. Also, the hydrochemical parameters of the environment and the feed base of the ponds were monitored, the values of which characterized the condition of the ponds as satisfactory for the cultivation of crayfish. The average daily water temperature during the work period was in the range of 24.0-25.0 ºC on average. It is determined that the optimal period of cultivation of ARCC under natural temperatures should be at least 3 months. The average weight of young crayfish planted in ponds for cultivation can be 0.2-8.0 g, depending on the tasks set: obtaining a larger number of crayfish within an average weight of 40 g, obtaining a smaller number, but larger individuals (60-80 g). It is most effective to plant juveniles of an average weight of at least 2 g in ponds. Cultivation of early ARCC juveniles in ponds in the South of Russia to produce commercial cancers is less effective, but it is possible due to the highest yield of commercial products per hectare of area among the groups of cancers under consideration. The hydrochemical regime of reservoirs must meet the biological requirements of the species. The condition of ponds, and in particular, the rapid development of aquatic vegetation in the water column during cultivation can significantly reduce the natural cancer productivity of reservoirs.