Saveljev A.P., Batbayar N., Boldbaatar Sh., Dashbiamba B. 2016. Self-eating in beavers — trophic opportunism or reaction on stress? Extreme case from Mongolia // Russian J. Theriol. Vol.15. No.1: 68–74 [in English].
Alexander P. Saveljev [corresponding author, saveljev.vniioz@mail.ru], Russian Research Institute of Game Management and Fur Farming, Preobrazhenskaya str. 79, Kirov 610000, Russia; Niamosor Batbayar, Administration of Tes sum, Zavkhan aymag, Mongolia; Shaariybuu Boldbaatar and Batseren Dashbiamba, Ministry of Environment and Green Development of Mongolia, Tes sum, Zavhan aymag, Mongolia.
ABSTRACT. For the purpose of preservation of a unique gene pool of autochthonous beavers Castor fiber birulai in 1985–2002 daughter population in adjoining regions of NW Mongolia and South Tuva (Tes River / Tesijn gol basin) has been introduced (Stubbe et al., 2005). Today this local population has reached 150 animals (Saveljev et al., 2015). The physical condition of the beavers that were caught by a sort of natural “ecological trap” late February, 2015 is described. As the result of extreme frosts animals have been blocked by frazil in the lodge and had no access to forage. Local people have released five animals from this ice captivity. All beavers had gnawed tails. Absence in this area of terrestrial large predators allows to assume with high degree of confidence that the reason of traumas at animals was self- (or allo-) gnawing. The facts of placentophagy and piscivory of beavers and infestation by opisthorchosis as well, as cases of predation and scavenging among mammals (the “obligate” phytophages) are discussed.
KEY WORDS: Castor fiber birulai, Mongolia, ecological traps, frazil, stress, self-gnawing.