Using the Maximum Possible Catch to Calculate the Abundance of Medium-Cycle Fish Species

The application of the maximum possible catch indicator in the cohort method of restored fish stock is analyzed. Using various model examples with a range of changes Mav = [0.22; 0.71], Fav = [0.09; 1.41] and a period of commercial exploitation of generations up to 13 years, it has been shown that the method gives satisfactory results for medium-cycle fish species with Mav = [0.24; 0.43] and F/Z = [0.30; 0.65]. The possibility of testing the admissibility of the method application is demonstrated. The need to develop this area for the study of natural mortality is noted. It is concluded that under certain conditions with a stationary level of exploitation, it is permissible to carry out population calculations with indirect consideration of the rate of natural mortality based on fishing mortality.