Congratulations on defending your PhD dissertation! - VNIRO
01 July 2025

Congratulations on defending your PhD dissertation!

In the third ten-day period of June 2025, Acting Head of the Laboratory for the Study of Fish Age and Growth at the Pacific Branch of the Russian State Research Center of Fisheries and Oceanography (VNIRO) Svetlana Leonidovna Ovsyannikova defended her dissertation "Pollock of the South Kuril Region (functional structure of the range, stock status, fishery)" for the degree of candidate of biological sciences in specialty 1.5.13. "Ichthyology".
 
The defense took place at a meeting of the dissertation council on 24.1.191.02 (D 005.008.02) at the Federal State Budgetary Institution of Science "National Scientific Center of Marine Biology named after A.V. Zhirmunsky" of the Far Eastern Branch of the Russian Academy of Sciences (NSCMB FEB RAS).
 
The main objective of the dissertation is to identify the population structure of pollock near the southern Kuril Islands for the rational exploitation of its stocks.
 
The arguments presented by the author are based on the analysis of a large array of data collected in the branch over a 25-year period of complex expeditionary research and monitoring of the pollock fishery.
 
The results obtained by Svetlana Ovsyannikova convincingly demonstrate the key provisions submitted for defense.
 
1. There are 3 spawning centers and, accordingly, 3 populations of pollock near the southern Kuril Islands and the Pacific coast of Japan: in the Volcanic Bay, the Kunashir Strait and the Prostor Bay. They are isolated spatially and by the timing of mass spawning.
 
2. The functional structure of the range of these populations was formed under the influence of a set of factors, the main ones being the timing of the onset of optimal hydrological conditions for reproduction and development of eggs and the latitudinal position of spawning centers, which determines the time of the outbreak of phytoplankton bloom and the conditions for pollock growth in the first year of life.
 
3. The state of pollock stocks in the South Kuril region is determined by the number and biomass of three populations and is currently estimated at an average level. For the rational use of pollock resources in the South Kuril zone, forecasting their state and determining the total allowable catch (TAC) must be carried out for populations separately, taking into account the state of the stocks of each of them.
 
The VNIRO team sincerely congratulates Svetlana Leonidovna on the defense of her PhD dissertation and wishes her further success in science!
 
VNIRO Press Service