Analysis of rodent populations in technogenically transformed areas (with reference to <Emphasis Type=Italic>Apodemus</Emphasis> (<Emphasis Type=Italic>S.</Emphasis>) <Emphasis Type=Italic>uralensis</Emphasis> from the EURT zone)

It is shown that the response of rodent populations to acute and chronic irradiation depends on its functional structure, i.e., on specific features of animals with two alternative types of ontogenetic development. Upon acute irradiation, sexually immature young of the year (animals with the second type of ontogeny) are most radioresistant. Exposure to chronic irradiation, as in the zone of the Eastern Ural Radioactive Trace (EURT), leads to an increase in the proportion of mature young of the year (animals with the first type of ontogeny), which are the most radiosensitive part of the population. The abundance and fecundity of mice in the impact zone are consistently higher than in the background zone, which improves the adaptive potential of the population. The role of species ecological specialization and configuration of the contaminated zone in the formation of migrant rodent population is emphasized. It is concluded that a high migration activity allows the pigmy wood mouse (a radiosensitive species) to avoid long-term radiation exposure.     

Variability of quantitative features of the head seismosensory system in European perch <Emphasis Type=Italic>Perca fluviatilis</Emphasis> L. under conditions of anthropogenic mineralization of ponds and medium-size reservoirs

The peculiarities of the quantitative manifestation of four meristic features of the head seismosensory system have been studied in European perch individuals that inhabit ponds and medium-size reservoirs in the Middle and Lower Kama basin. The reduction trend in the interpopulation variability in the total average value of these features has been revealed under conditions of increasing mineralization of freshwater bodies, which is due to chemical pollution entering from transformed areas of their catchments.     

Traditional management and conservation of shea trees (<Emphasis Type=Italic>Vitellaria paradoxa</Emphasis> subspecies <Emphasis Type=Italic>nilotica</Emphasis>) in Uganda

Traditional practices are universally recognised as a basis for conservation of biodiversity. However, such practices are often not included in natural resource conservation policies. This study assessed local conservation practices of shea trees (Vitellaria paradoxa) within different farming systems in Uganda and developed conservation guidelines for the species. The assessment involved 300 respondents, 15 focus groups and 41 key informants. Content analysis was used to identify the most important management and conservation practices. Local uses were categorised on the basis of shea tree products while differences in conservation practices were analysed using the Friedman test. The results show that eight shea tree products are used for 36 different purposes. Respondents’ age significantly influenced their knowledge about the shea tree. Traditional conservation practices include on-farm retention during cultivation and the use of folklore (mainly taboos), customs and rituals. Traditional management practices include weeding, bush burning, pollarding and pruning. Based on the current management and traditional conservation practices, a framework for the conservation of shea trees is proposed for integration into conservation policy decisions.     

Changes in the Species Composition of Parasites in European Perch, <Emphasis Type=Italic>Perca fluviatilis</Emphasis>, in Lake Gusinoye (Lake Baikal Basin) during Depression and Subsequent Recovery of Host Abundance

Changes in the species composition of parasite fauna in the European perch in Lake Gusinoye (the Lake Baikal basin) were analyzed in the periods before and during depression of host abundance (the early and late 1970s) and in the years of its recovery to a stable level (the mid-2010s). The period of depression was associated with a significant decrease in the species richness of parasite fauna. Subsequent recovery of perch abundance to a stable level resulted in an increase in the parasite species richness, but it remained lower than before the depression of host abundance.     

Changes of leaf morphology in <Emphasis Type=Italic>Betula pendula</Emphasis> roth and <Emphasis Type=Italic>B. pubescens</Emphasis> Ehrh. along a zonal-climatic transect in the Urals and Western Siberia

Leaf size, shape, and parameters of venation in Betula pendula and B. pubescens have been studied along a 1600-km latitudinal zonal transect in the Urals and Western Siberia. The results show that leaf size and venation density depend on the geographic location of population, with these parameters in the two species changing in opposite directions along the transect. In its northern part (forest tundra-southern taiga), B. pubescens shows a positive correlation of leaf area with long-term-average air temperature, while this correlation in B. pendula is negative. In the southern part, correlations of leaf size with long-term average precipitation in the two species are also opposite in sign. Parameters of leaf shape in both species depend mainly on weather conditions in the current year rather than on long-term average climatic parameters. The conclusion is drawn that B. pendula and B. pubescens have different mechanisms of structural adaptation of leaves to climate and weather conditions that are based on changes in leaf size and shape.     

On the term <Emphasis Type=Italic>Station</Emphasis> used in Russian ecological and faunistic literature

The history of the term station (in Russian, statsiya) in the Russian ecological and faunistic literature, interpretation of its meaning by different authors, and relationships between the terms station, habitat, biotope, and ecological license are discussed. It is suggested that station should be interpreted as the entire set of all external conditions affecting a population, which is observable as a part of physical space possessing certain properties.     

Variability of Demographic Parameters in a Cyclic Population of the Bank Vole (<Emphasis Type=Italic>Clethrionomys glareolus</Emphasis>)

Analysis of demographic parameters in a local bank vole population has shown that different relationships exist between them. The level of population abundance is directly correlated with the proportion of sexually mature juveniles, the length of the breeding season, and the age of overwintered individuals. The duration of the breeding season shows a delayed dependence on population abundance in the previous year. Variation in the average age of overwintered voles at different phases of the population cycle is characterized by a delayed dependence on the length of the breeding season in the previous year. Intrinsic factors generate the cyclic dynamics of parameters, while extrinsic factors can modify their dynamics.     

Specific ecological features of the brown bear (<Emphasis Type=Italic>Ursus arctos</Emphasis> L. 1758) in Yakutia

In Yakutia, the brown bear inhabits the forest and forest-tundra zones. Compared to bears from other regions of Russia, Yakutian bears have slightly smaller body and skull sizes and are mainly herbivorous, with their wood spectrum being relatively narrow. Their fecundity averages 1.68 cubs per parous female. The bears make their dens at a depth reaching 2.5–3 m. The denning period begins early and is 195–210 days long. An electroencephalographic analysis of the effect of a 1–10 kDa peptide fraction from the bear brain on Wistar rats has shown that wintering bears are in the state of sleep, or “superficial hibernation.”     

Insularization and polymorphism in marginal island populations of <Emphasis Type=Italic>Pinus sylvestris</Emphasis> L.

Comparative allozyme analysis of 26 marginal island populations of Pinus sylvestris L. and 20 populations from the center of the species range has confirmed, at the species level, the Wright-Dubinin “island model” of automatic genetic processes and Mayr’s hypothesis about homozygotization of small isolated populations at range boundaries. It has been shown that the polymorphism of isolated populations sharply decreases when their area is reduced below 15–20 km² and increases to the level observed in the center of the range when the population area exceeds 50–100 km². A chorogenetic classification of marginal P. sylvestris populations is proposed.     

Factors influencing the duration of gypsy moth (<Emphasis Type=Italic>Lymantria dispar</Emphasis> L.) population outbreaks

For the first time, an attempt has been made to reveal possible causes of the relative “brevity” of gypsy moth outbreaks in the Russian Far East. The results show that major factors limiting these outbreaks include the weakly manifested seasonal drift of gypsy moth foci, oviposition habits, as well as specific weather conditions during the period of larval development and death that facilitating the dispersal of insect pathogens in components of the forest ecosystem.