Bolshakov V.N., Vasilev A.G., Vasileva I.A., Chibiryak M.V.
POPULATION ECOLOGY OF SMALL MAMMALS IN FLOOD-PLAIN FORESTS OF SAKMARA RIVER (ORENBURG REGION) ^{[№ 10 ' 2015]}
During field study period since 1972 up to 2015 in two localities of Orenburg region (Kuvandyk city and Chorny Otrog township) at flood-plain forests of Sakmara River and some other attached biotopes, including steppe fragments, we found 19 species of rodents and 6 species of insectivorous mammals. For the above time interval we revealed a decrease of proportion of some species and taxonomic groups in the structure of communities of small mammals. Among them there were: gray voles of genus Microtus (arvalis, agrestis, oeconomus), the Northern Birch Mouse (Sicista betulina), shrews of genus Sorex (araneus, minutus), however the Striped Field Mouse (Apodemus agrarius) was identified in last years (2010, 2014–2015) only. Using long-term July data on small mammals trapping at flood-plain forests of Sakmara River since 1986 up to 2015 year period we found parallel decrease of biological diversity in the two localities inferred from 10 biodiversity indices assessing species richness, dominance, diversity and evenness. In Chorny Otrog locality the dominant relations among species within community were changed in just recent years: now the Pigmy wood mouse (Sylvaemus uralensis) became a dominant (the most abundant) species instead of the Bank vole (Myodes glareolus). Population ecology analysis of Bank voles and Pigmy wood mouse has revealed parallelism in changes of their population features (age ratio and some reproductive indices) connected with conditions of the year of comparison. The rate of reproduction in populations of both species decreased in 2015 in comparison with 1986. Differences between populations as well as between species were expressed lower than those between years.

Bolshakov V.N., Vasilyev A.G., Vasilyeva I.A., Gorodilova Yu.V., Lyubashevskii N.M., Chibiryak M.V.
MORPHOLOGICAL VARIABILITY OF PYGMY WOOD MOUSE SYLVAEMUS URALENSIS SOUTH URAL: TECHNOGENEOUS ASPECT ^{[№ 12 ' 2011]}
Variability of the small wood mouse (Sylvaemus uralensis Pallas, 1811) mandible shape by geometric morphometrics methods was studied in the Southern Urals. Nonspecific morphogenetic reaction of the species to the influence of technogenic factors of different origin (fluorides, radionuclides) was revealed. It was established, that landscape-biotopical and technogenic components bring the different contributions into the general variance.