The aim of the research was to assess the physiological state of salmon, their distribution, nutrition, assessment of the abundance of their food supply and background conditions. For juvenile salmon, especially for pink salmon, this period is critical for survival. In some years, mortality occurred above the average annual level, which subsequently affected the volume of approaches. To get closer to unraveling this mechanism – what more and what less affects the survival of salmon and how it spends the cold season, scientists went on a winter expedition to its feeding grounds.
The area of research covered the places of mixed concentrations of Russian and American herds south of the Aleutian Islands. Experts have collected extensive material on the biology and ecology of salmon and their habitat.
"During the filming, we noted almost all types of Pacific salmon, except for sima, sockeye salmon prevailed in this area," said Alexey Somov, head of the expedition, head of the sector for studying the marine life of salmon. – The salmon was well-fed, there was no shortage of fodder, previously its physiological condition can be assessed as satisfactory."The large number of sockeye salmon in catches is explained by the appearance of a high-yielding generation of North American origin. The total number of Pacific salmon in the surveyed water area of 530 thousand square kilometers was estimated at 140 million specimens.
A huge volume of samples was also taken for laboratory analysis on the shore, thanks to which it will be possible to fully assess the condition of the salmon, as well as determine its origin. During the filming, the latest methods of collecting traces of genetic material in the water (eDNA analysis) were used, which allow us to judge the presence of specific species in this area. Work with samples will be carried out in VNIRO and its Far Eastern branches. NPAFC specialists intend to exchange the collected information and prepare a series of joint scientific papers reflecting new steps in the study of mysterious salmon.
Research took place in difficult weather conditions. Winter storms in open Pacific waters are a formidable phenomenon, which is why salmon feeding surveys are so rare and the information obtained in them is so valuable. However, the scientists were able to continue their research, despite the bad weather, showing once again fortitude and professionalism.
VNIRO management thanks all participants for conducting a successful international expedition.
VNIRO Press Service
