The press service of the Kronotsky Nature Reserve has reported on the research of the sockeye salmon spawning stock conducted by scientists in the South Kamchatka Sanctuary. Monitoring of its reproduction in the shallow waters of Kuril Lake has been ongoing for four years.
After entering fresh waters from the sea, part of the mature individuals chooses rivers and streams for spawning. At the same time, another part equips spawning grounds in the coastal area of Kuril Lake. Moreover, sockeye salmon arrange spawning grounds in strictly defined areas.
Scientists conduct observations using aerial photography with an unmanned aerial vehicle. They managed to create a map of littoral spawning grounds for sockeye salmon, the location of which is taken into account when planning tourist routes.This is necessary to exclude the potential negative impact of motorized vessels on the reproduction of salmon.
Scientists note that this year, the construction of nests in littoral spawning grounds is much more intensive than in the period from 2021 to 2023. Already in mid-August, those spawning grounds that were usually built only by the end of the first decade of September were equipped and numbered at least a hundred nests. At the same time, sockeye salmon continue to use the spawning sites already known to scientists, and the appearance of new spawning grounds is not observed.
Littoral spawning can serve as an ecological indicator of the well-being of both the sockeye salmon population of Kuril Lake and the ecosystem of the water body and its surroundings. A long-term series of observations will make it possible to assess the variability of the timing of appearance, intensity, and localization of littoral spawning grounds and to timely identify violations if deviations of this process from the already known scenario are detected at some point.