In the sea, the bulk of the catches were Czech-Pechora herring, which rushed to the coastal zone for spawning grounds. Thanks to the intense heating of the coastline, spawning began at the usual time, although ice was still floating in the bay. The catches also included Asian smelt, river and polar flounder, and navaga.
On the river Wolong experienced high water levels, which made research difficult. However, work was carried out to collect biological material in the lower reaches of the river. Wolongs during the migration of juveniles of autumn-spawning fish species (Atlantic salmon, brown trout, pink salmon), for which net traps were installed. The catches included pink salmon, minnow, baleen loach, and three-spined stickleback.
Near the mouth of the river. Arctic char were regularly found in net catches in Wolong. A biological analysis was carried out, including determination of size and mass characteristics, sex ratios in fish populations, and stages of gonad maturity. Most of the char (98%) descended to the sea after spawning and had gonads at maturity stage VI-VII. To assess the age structure of the population, otoliths and vertebrae were taken.
For the second year in a row, employees of the Northern Branch of VNIRO have been tagging salmon and brown trout to assess their growth dynamics. This year, brown trout were caught and tagged in 2023. Over the year, the increase in length was 12 cm. This work will continue.
The collected material will be used to assess the abundance of aquatic biological resources, prepare forecast materials, substantiate the raw material base of fisheries, as well as develop measures to regulate fisheries.
VNIRO press service