Commercial Zoning and Delineation of Reproduction Areas of the Far East Salmon

摘要

Abstract Pacific salmon (pink salmon, chum salmon, sockeye salmon, etc.) are one of the most important commercial objects of the Russian Far East with an annual catch of 300 to 500 thousand tons. They spawn in rivers and freshwater lakes on a vast territory from Chukotka to the South Kuriles and Primorye. The organization and control of their fishing and reproduction are based on zoning of their species range. The current federal commercial zoning divides the marine waters into fishing areas (zones and subzones) in which salmon (and other species) are mainly harvested and for which annual predictions of return are given and fishing statistical reports are formed. The shore border of zones and subzones is determined along the coastline by the level of the maximal tide, and thus the spawning sites of Pacific salmon are not covered by commercial zoning. Therefore, in parallel, zoning of salmon spawning rivers and lakes is required to correlate with commercial zoning and a strategy for the reproduction and conservation of these economically important species of anadromous fish needs to be developed. A general algorithm is suggested for dividing the territory, as well as the flora and fauna inhabiting it, into ecogeographic regions (EGRs) based on ecological and geographical criteria. Accordingly, the territory of the Russian Far East was parsed into more than 30 EGRs, which can be taken as terrestrial complexes of spawning lake-river systems (complementing them with the adjacent coastal marine waters, where smoltified juveniles journey downstream), where the next generations of salmon reproduce and survive the early, critical period of life, and where the main potential of their abundance is formed. It is shown that the ecogeographic areas mainly correspond to the fishing areas of Pacific salmon. This means that the issues of fishing and reproduction are interrelated for regional salmon stocks reproducing in this ecogeographic area, and therefore are subject to a unified management plan. In relation to a given species of salmon fish, the territorial network of the EGRs can be further subdivided into ecogeographic units (EGUs), taking into account the ecological and genetic differences between population groupings. EGUs can be considered as the basic units of reproduction of this species. Further, the set of multi-species EGUs for all salmon species (and possibly other organisms) within a given EGR forms an ecogeographic aggregation (EGA), which can be interpreted as a management unit of all biological resources in a given ecogeographic region.