Estimation of the value of unreported and unregulated commercial and recreational fisheries at inland waterbodies: case study on the Kama reservoir (Perm krai)

Abstract

The results of the possible volume of fish harvetsed annually by unreported and unregulated commercial and recreational fisheries at Kama reservoir for the period of 2011–2021 are presented. Two approaches were used to assess the unaccounted commercial catch. The first method is based on the comparison of official commercial catches with scientific research data collected during the surveys of commercial fisheries on the reservoir. The second approach is based on official statistics on the number of fishing gear used by commercial fisheries and the real CPUE values for fished species. The volume of recreational catches is estimated by the number of anglers per unit area of the reservoir, seasonal dynamics of visits to the reservoir by anglers, and the species structure of anglers catch. We found that the volume of possible average annual unaccounted commercial and recreational fish catch may exceed the official data by 2–2,5 times.