COMPLEX MONITORING OF SALMON SPAWNERS ESCAPEMENT TO THE KAMCHATKA RIVER IN REAL TIME REGIME

Abstract

Complex method of quick quantitative evaluation of the spawners escapement to the Kamchatka River is developed for pacific salmons on the base of analysis of their passing dynamics through certain parts of the river (main stream, tributaries, spawning grounds). The runs of different temporal forms of anadromous salmons were separated taking into account their biological parameters using the data of biological analysis of commercial catches in Ust-Kamchatsky district. The spawners abundance was evaluated from CPUE value for the main stream where control catches of spawners were made in the periods predetermined for escapement, and directly using two duplicate hydroacoustic complexes for the tributary important for salmons reproduction or visually from ashore, boats, or flying vehicles for other tributaries. These data were coupled with general assessments of the escapement values in the river basin from helicopters. Numeral model was developed to evaluate the salmons escapement to the spawning grounds. The escapement dynamics was simulated retrospectively for sockeye, chum and coho salmon in 2016 and 2017. The method was successfully used for fishery management in the fishery campaign of 2018. Efficiency of the fishery regime was estimated using this approach. The value of sockeye salmon escapement was determined as enough for medium reproduction, and the values of chum and coho salmons escapement — as enough for medium or high reproduction. For chinook salmon, the model was not tested, but the method of control catches was developed and applied as a part of integrated methodology for quantitative operational assessment of escapement.

Keywords

• kamchatka river
• pacific salmon
• hydroacoustic complex
• aerial survey
• numeral model