Scientists from the Kamchatka Research Institute of Fisheries and Oceanography and the Severtsov Institute of Ecology and Evolution of the Russian Academy of Sciences (IEE RAS) have discovered and described the biological characteristics of the three-toothed lamprey Entosphenus tridentatus in the sea waters of the Kuril Islands.
The three-toothed lamprey is a migratory parasitic species that migrates to feed in the waters of the Pacific Ocean. Its spawning grounds are concentrated in rivers along the North American coast from California to Alaska and the Aleutian Islands, as well as in the rivers of the Japanese islands of Hokkaido and Honshu. The biology of the species in fresh water has been well studied, but information on its behavior at sea remains limited, which is due to the difficulty of catching it at sea. Cases of catching two individuals of the three-toothed lamprey in the northwestern Pacific Ocean have expanded our knowledge of the morphological characteristics and biology of this species during its marine life.
In June 2023, two lamprey specimens were caught in the exclusive economic zone of Russia; their external structure and tooth formula are typical for the species. Analysis showed that the specimens were immature and feeding at a depth of 32–45 m, where they followed schools of Pacific salmon.
The data obtained confirm the idea of significant (over 5 thousand km) feeding migrations that representatives of this species can make in marine waters.
The article was published in the specialized journal Research of Aquatic Biological Resources of Kamchatka and the Northwestern Pacific Ocean.