Actual and Model-Based Assessment of Castor Fiber Populations for Different Reserves in the European Part of Russia and Their Impact on Ecosystems

Abstract

The analysis of restoration of the number of Eurasian beaver (Castor fiber L.) in the reserves of the European part of Russia and the prediction of possible changes in ecosystems after its introduction into the reserves (Laplandsky, Darwinsky, Prioksko-Terrasny, Central Forest, Oksky, Mordovsky, Khopersky, Voronezhsky and Rdeysky) is presented. The purpose of this work is to analyse the patterns of restoration of the number of beavers based on long-term ground-based observation data and a qualitative description of possible changes in ecosystems after the introduction of beavers. The analysis of the population dynamics of the beavers in the reserves located in the north, south and in the centre of the range was carried out based on long-term monitoring data from 15 to 80 years. It is shown that the patterns of beaver population dynamics can be described using four types of patterns: eruptive; single-stage with quasi-periodic oscillations, multi-stage with quasi-periodic oscillations and a logistic trend of population change with periodic oscillations around it. It is revealed that the impact of beavers on landscapes depends on the population density, terrain features and forage resources of the territory. It is shown that in the future the beaver remains a constant component of ecosystems in the major part of the range. Possible changes in the biotic and abiotic characteristics of ecosystems as a result of beaver activity are analysed.