On November 29, 2017, Vyacheslav Stepanovich Labai, Candidate of Biological Sciences, Leading Specialist of the Laboratory of Hydrobiology of the Scientific Research Institute of Advanced Development at the Sakhalin State University, delivered a lecture «Watercourses of Sakhalin Island. Life in Flowing Water» in the Sakhalin Regional Museum as part of the lecture series «Natural History of Sakhalin and the Kuril Islands». The lecture was attended by museum specialists, students of Yuzhno-Sakhalinsk Pedagogical College of Sakhalin State University, as well as people interested in this topic.
During the lecture, the term «watercourse» was explained; a detailed classification of watercourses and characteristics of the river network of the island region were given. There are more than 60 thousand rivers on Sakhalin Island; the largest ones are Poronay and Tym. And among the lakes the largest are the Nevskoye Lake (in Poronaisk area) and the Lake Tunaycha, which is also called the «lake of running water» (in Korsakov area).
Vyacheslav Stepanovich told about the representatives of the aquatic population, the role and interconnection of watercourses and humans. The attendees learned about the sources of the feed resource for aquatic biota, the distribution of cadaveric organics, the role of catastrophic phenomena in the existence of the «salmon» river of Sakhalin. Vyacheslav Stepanovich dwelled on his analysis of the seasonal variability of the main zoobenthos communities in various sections of the watercourses and a comparative analysis of the drift biomass in various sections of the major rivers of Sakhalin.
He raised the problem issues such as protected species of mollusks and fish in Sakhalin, including Sakhalin taimen the ancestor of all salmonids. The lecturer reminded that taimen is the largest freshwater fish, the number of which has declined sharply over the past 10 years. December 19, 1997 is the date when the conservation of this species began formally. The attendees learned about the status of the Sakhalin Taimen program and the National Strategy for the Conservation of the Sakhalin Taimen.
Vyacheslav Stepanovich also told about a five-year pessimistic and optimistic forecast for the taimen population taking into account the main threats to the existence of the taimen population.
The river system is very complex that is why it is so important to provide information to the public and discuss the above problems openly and comprehensively. Questions were asked at the end of the lecture.