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The state of food resources for Eurasian beavers (Castor fiber Linnaeus, 1758) after several cycles of habitat colonization and abandonment has been analyzed in three beaver settlements on small rivers of Novgorod oblast. It has been shown that tree stands surrounding the settlements differ in composition and degree of damage but are similar in that they contain no forage for beavers: aspen is absent, and birch trees are large and require great efforts to cut them down and utilize. The undergrowth and understory also contain no aspen, while abundant willows and birch are represented by young, thin stemmed plants unevenly distrib uted over the area. Tree species prevailing in abandoned settlements are not favored by beavers, implying that the animals must have expended extra energy for foraging. Supposedly, populations of beavers on small rivers in the southern taiga subzone, in habitats modified by their activities, will maintain their abundance far below the maximum possible level, depending on the rate of forage plant regrowth against the background of dete riorating habitat quality.

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