Interspecific interactions of amphipods <Emphasis Type="Italic">Gammarus lacustris</Emphasis> and <Emphasis Type="Italic">Gmelinoides fasciatus</Emphasis>

Experimental studies of interactions between two amphipod species (Gmelinoides fasciatus and Gammarus lacustris) showed that predation is the basic mechanism accounting for their mutual exclusion in nature. Mortality from predation among similar-sized specimens of both species at an equal abundance ratio was similar (24–25% in G. lacustris and 27–30% in G. fasciatus). The displacement of G. lacustris by G. fasciatus was observed when the latter was dominant. Adult G. fasciatus and G. lacustris successfully preyed on juveniles of their competitors and did not differ significantly in daily food consumption as a percentage of body weight: 6–24% at a fresh body weight of 18–24 mg in both species. The potential for rapid population growth under new conditions contributed to the success of the invasive Baikal species G. fasciatus in displacing G. lacustris from many water bodies of Russia.     

Plasticity in metamorphic traits of <Emphasis Type="Italic">Rana kukunoris</Emphasis> tadpoles: The interactive effects of food level and rearing temperature

Larval amphibians are particularly likely to encounter variation in rearing temperature and resource availability due to variation in aquatic breeding habitats. In this study, plasticity in growth rates, larval mass, larval period, and size at metamorphosis were examined in Rana kukunoris Nikolskii, 1918 under different combinations of temperature and food level. Larval period and larval body mass was sensitive to food level, and varied with temperature. Tadpoles metamorphosed at an older age at low temperature than those reared at warm temperature. Food level was a significant affect on larval period at low temperature, but not at warm temperature. Mass was heavier for tadpoles reared at low temperatures than those reared at warm temperatures. The effect of food level depended on temperature, because larvae reared at low temperature that were offered a high food level achieved a larger size than larvae offered a low food level, but this did not occur at warm temperature. Therefore, we suggest that high food availability at low temperature prolonged developmental periods, thus larvae are larger as metamorphs than those reared at warm temperatures.     

The role of rapid induced resistance of host plant in trophic interactions between <Emphasis Type="Italic">Betula pendula</Emphasis>, <Emphasis Type="Italic">Lymantria dispar</Emphasis>, and <Emphasis Type="Italic">Bacillus thuringiensis</Emphasis>

Life history traits of gypsy moth larvae markedly decrease under the effect of host plant insect resistance, but no significant changes occur in immunity parameters such as hemolymph phagocytic activity and lysozyme-like activity of hemolymph plasma and midgut tissue; moreover, alkaline protease activity in the midgut contents becomes higher. The actual sensitivity of the larvae to Bacillus thuringiensis remains unchanged.     

Ecological Groups of the Daubed Shanny <Emphasis Type="Italic">Leptoclinus maculatus</Emphasis> (Fries, 1838), an Arcto-boreal Species,Regarding Growth and Early Development

The patterns of growth and development have been studied in L. maculatus early life stages of different ecological groups (pelagic and demersal) from Kongsfjorden and Billefjorden (the northwestern coast of West Spitsbergen). It has been found that the growth rate of larvae markedly increases by age 2+ (stage L2), which is due to their transition to exogenous feeding. Consideration is given to changes in the length and condition of the lipid sac (a provisory organ) in the period of its formation, growth, and resorption in the course of ontogeny. The lipid sac reaches the maximum size at stage L4* and is resorbed at stage L5. Analysis of individual variation in the size and body weight of fish early life stages provides the possibility to evaluate the adaptation capacity of a species under specific conditions of the Arctic.     

Prospects of using mosses (<Emphasis Type="Italic">Fontinalis antipyretica</Emphasis> Hedw. and <Emphasis Type="Italic">Pylaisia polyantha</Emphasis> (Hedw.) Bruch et al.) as indicators of environmental contamination with heavy metals

The contents of Al, Ti, Fe, Cr, Cu, Zn, As, Se, Cd, Pb, and rare earth elements (REEs) were determined in mosses (the hydrophyte Fontinalis antipyretica and the epiphyte Pylaisia polyantha) by the inductively coupled plasma-mass spectrometry (ICP-MS) method. These plants were used for estimating the spatial distribution of heavy metals (HMs) in the basins of small and medium rivers of Vologda and Kostroma oblasts (Russia). It was shown that water mosses are good indicators of REEs and epiphytic mosses, of the pollutant metals Cu, Zn, Se, and Pb. The epiphytic and hydrophytic mosses did not differ in the macroelement (Al, Ti, and Fe) content.     

Remote effect of nuclear polyhedrosis virus on the gypsy moth (<Emphasis Type="Italic">Lymantria dispar</Emphasis> L.) in its natural environment

The remote effect of the nuclear polyhedrosis virus on the gypsy moth was studied for the first time under natural conditions. In the generation that developed from infected eggs, the weight of pupae was reduced, sex ratio was altered, and female fecundity and egg fertility were lower than in control individuals. The F₁ progeny of these moths were characterized by an increased rate of latent virus carriage and high mortality caused by the combined effect of polyhedrosis and insect parasites.     

Mating patterns in three <Emphasis Type="Italic">Bufo andrewsi</Emphasis> populations at different latitude

Body size-dependent mating pattern is thought to a consequence of the sexual selection on phenotypic characters. In the view, we investigated the mating patterns in Bufo andrewsi from three populations at different latitude in three Nature Reserves (i.e. Wanglang, Yele and Fengtongzhai) in China from early- March to late-May 2013 and 2014. The results showed that average body size did not differ significantly between amplectant and non-amplectant males within each population. We found a significantly positive relationship in body size between the amplectant males and amplectant females in Wanglang population, but not in Qiqiao and Yele populations. The strength of size-dependent mating was not correlated with the malebiased operational sex ratios (OSRs), suggesting that intensity of male-male competition at nights do not result in variation in size-dependent mating patterns in B. andrewsi among populations.     

Trophic factor during the transition of peled (<Emphasis Type="Italic">Coregonus peled</Emphasis> Gmelin) larvae to active feeding in their native range

With regard to published data on the ecology of early peled larvae acclimated in lakes or reared under experimental or fish farm conditions, interannual variability of feeding and environmental conditions during the transition to exogenous feeding has been demonstrated for peled larvae in a control water body located in the floodplain of the main spawning tributary of the lower Ob River. The conditions that govern exogenous food consumption by early peled larvae and largely determine the fate of a given generation depend on both biotic (the concentration of food organisms) and abiotic factors (wind regime). The trophic optimum during the transition of larvae to exogenous feeding, which ensures the level of gut filling sufficient for their survival and growth in the control water body, is determined by a complex of natural events. The results of this study may be extrapolated to the entire native range of the Ob River peled population and used for planning the release of peled larvae into natural water bodies of Western Siberia to compensate for losses to their biological resources.     

Influence of experimental conditions on manifestation of the group effect in the gypsy moth, <Emphasis Type="Italic">Lymantria dispar</Emphasis> L.

The effect of rearing conditions for gypsy moth larvae on parameters of their development (its duration and mortality) was studied in experiments with early instar larvae reared singly or in groups. The manifestation of the group effect was analyzed depending on the choice of experimental unit (the larva or the rearing container) and the amount of volume per larva. The observed effects were evaluated quantitatively.     

<Emphasis Type="Italic">Pueraria lobata</Emphasis> is expanding and endangering in China ecosystems

Kudzu (Pueraria lobata) is an aggressive invasive species and has brought great loss world-widely. Though it is originated in China, it has not been considered as a weed in China. While more and more articles report its destructive effects on the native community throughout the whole country. We conducted an experiment to validate whether kudzu could endanger its native ecosystem and wanted to find the reason of its fast spreading from 2008 to 2010. Concentrations of nitrogen and phosphorus, water content, irradiance, pH, species number and aboveground biomass in the three sub-communities (Kudzu, Mixed and NonKudzu) were analyzed. Meanwhile, light irradiance and coverage of kudzu at 0, 25, 50, 100, 500, 1000 and 2000 m distance from the road surface verge were also measured. The results showed that kudzu evidently lowed the species biodiversity and obviously changed the water, light and nutrient cycles in its expanding area. Kudzu’s rapid expansion is mainly because it can get full available space and light for growth by reason of anthropogenic disturbances. Our results indicated that Kudzu was a potential weed in China if great land changes from human activities are continuing.     

Ecological-demographic characterization of <Emphasis Type="Italic">Potentilla bifurca</Emphasis> L. cenopopulations

A discrete approach to the study of ontogeny has made it possible to reveal a high degree of age heterogeneity in P. bifurca cenopopulations. The basal ontogenetic spectrum of cenopopulations has been determined. The index of regeneration is higher in cenopopulations of the young type and decreases in cenopopulations of the old type, whereas the situation with the index of senescence is inverse. The density of cenopopulations depends mainly on parameters of the substrate (density, composition, and moisture), its slope, and the intensity of plant vegetative reproduction and spread.     

Comparative analysis of the effect of predator odor on morphological and physiological parameters of adult male Campbell hamsters (<Emphasis Type="Italic">Phodopus campbelli</Emphasis>) and dwarf hamsters (<Emphasis Type="Italic">Phodopus sungorus</Emphasis>)

The effect of long-term exposure to natural excretions of the European polecat on the morphological parameters and hormonal status of adult male Campbell hamsters (Phodopus campbelli) and dwarf hamsters (Ph. sungorus) was studied. Exposure to volatile components of natural excreta of a potential predator did not have any significant effect on hamsters. The combined influence of volatile and nonvolatile components of the polecat’s excretions caused physiological stress in Ph. campbelli, while in Ph. sungorus, on the contrary, an increase in thymus weight and the plasma testosterone level was recorded.     

On sexual dimorphism in the winter diet of the sable (<Emphasis Type="Italic">Martes zibellina</Emphasis> L.)

The contents of the digestive tract in sables (Martes zibellina L.) of known sex and age from the Middle Kolyma basin were examined to assess the winter diet in general and the frequencies of particular types of food in different sex and age groups of these animals. No statistically significant sex-related differences in the diet were revealed. This is probably explained by a considerable overlap of size and weight parameters between male and female Kolyma sables, due to which probable differences in their diets are leveled off.     

Effect of temperature and precipitation on linear increment of <Emphasis Type="Italic">Sphagnum fuscum</Emphasis> and <Emphasis Type="Italic">S. magellanicum</Emphasis> in Western Siberia

The linear increment of Sphagnum fuscum and S. magellanicum in ombrotrophic mires of Western Siberia has been measured during two years over a transect about 2500 km long extending from forest–steppe to forest–tundra. Along the latitudinal gradient, the increment of both species has proved to be correlated with annual average air temperature and, in S. magellanicum, also with annual precipitation. The determinants of their growth differ between the southern, central, and northern parts of the study region. At the regional level, the annual and summer precipitation plays a more important role than the average air temperature. The increment of S. fuscum in the southern part is positively correlated with the amount of precipitation and negatively correlated with summer temperature, whereas the situation in the central part is inverse. In S. magellanicum, the linear increment is directly dependent on the annual average temperature and annual and summer precipitation in the south and on the annual and summer precipitation in the north of Western Siberia. The dynamics of linear growth of both species in bog pine forests during the growing season are similar: its rate is the highest in June, when the linear increment of S. fuscum and S. magellanicum amounts to 60 and 85% of the annual total, respectively.     

Spatiotemporal distribution of caddis fly larvae <Emphasis Type="Italic">Aethaloptera evanescens</Emphasis> MacLachlan, 1880 (Trichoptera: Hydropsychidae) in the Selenga River

Data on the occurrence, abundance, and biomass of caddis fly larvae Aethaloptera evanescens in the Selenga during the ice periods of 1987–2005 are presented. These insect larvae prefer river stretches with a gravel-sand ground, flow rate of 0.3–0.4 m/s, and depth of 2–3 m. Probable factors determining their distribution in the Selenga in recent years are a considerable drop of water level in the river (1995–2005), the improvement of hydrochemical conditions, and the presence of suspended and drifting erosion materials entering the river as a consequence of sand-gravel mixture excavation between 1980 and 1990.     

The diet of Asian badger, <Emphasis Type="Italic">Meles leucurus</Emphasis> Hodgson, 1847, in Samarovskii Chugas Nature Park,Western Siberia

The diet structure of Asian badgers (Meles leucurus Hodgson, 1847) on Bol’shoi Chukhtinskii Island (Samarovskii Chugas Nature Park, Khanty-Mansi Autonomous Area) was studied by means of coprological analysis. Ten diet components were identified, including Siberian stone pine seeds (pine nuts), berries, earthworms, larval and adult insects, fishes, amphibians, reptiles, and mammals. The proportion of pine nuts was especially large. Seasonal fluctuations in the occurrence frequency and abundance of different foods were insignificant, but some of them were found to markedly vary between years.     

Dynamics of motor asymmetry profiles in striped field mouse (<Emphasis Type="Italic">Apodemus agrarius</Emphasis> pall.) populations

The ratios between individuals with different signs of motor asymmetry (right-pawed, left-pawed, and ambidextrous) were estimated in two urban populations of striped field mice. Right-pawed mice were prevailing in both populations. An increase in the stress of regulatory system (stress index) in mice from these populations was accompanied by a shift of the asymmetry profile towards a greater proportion of left-pawed mice. The ratio between the numbers of right-pawed and non-right-pawed animals varied with time with a period close to that of the population dynamics. Apparently, the changes in the asymmetry profiles reflected population rearrangement: dominance of animals with a specific set of physiological, ecological, and behavioral characteristics gave way to an increased proportion of animals with a different set of characteristics. Qualitative differences between right- and left-pawed animals are evidenced by the specific characteristics of behavior and humoral immunity found in animals differing in motor lateralization.     

Composition of pied flycatcher (<Emphasis Type="Italic">Ficedula hypoleuca</Emphasis> Pall.) nestling diet in industrially polluted area

The composition of pied flycatcher (Ficedula hypoleuca Pall.) nestling diet was studied in the zone of strong pollution with emissions from the Middle Ural Copper Smelter (Revda, Sverdlovsk oblast) and in the background area from 2005 to 2007. The results show that diversity of the diet decreases and prevalence in it of one insect taxon (Lepidoptera) increases near the source of emissions. The proportion of uncharacteristic food objects (orthopterans, herpetobiont invertebrates) and variation in the size of invertebrates brought by parents to their nestlings increase, which is explained by degradation of forest habitats in the polluted area. Pied flycatchers provide nestlings with sufficient quantities of food, but its quality in the polluted zone is lower than in the background area.     

Effect of illumination regime on life span in <Emphasis Type="Italic">Drosophila melanogaster</Emphasis>

Accelerated aging of Drosophila strains with impaired detoxification of free radicals (Sod) and DNA repair (mus-210) under illumination as compared to the wild type has been demonstrated. In contrast, in a strain carrying a defective homolog of mammalian gene PCNA, the life span increases under conditions of round-the-clock illumination compared to constant darkness. The first review of the possible mechanisms underlying the effect of the illumination regime on the life span is presented, with special emphasis on the roles of the disturbance of normal circadian rhythms, increase in fecundity and physical activity (metabolic rate), and the neuroendocrine control of the insulin/IGF-1 pathway.     

Halotolerant bacteria of the genus <Emphasis Type="Italic">Arthrobacter</Emphasis> degrading polycyclic aromatic hydrocarbons

Eight strains of bacteria capable of degrading polycyclic aromatic hydrocarbons have been isolated from soils and bottom sediments sampled in the region of Verkhnekamskoe potash deposit (Berezniki, Perm krai) and classified with the genus Arthrobacter on the basis of phylogenetic analysis (16S rRNA genes) and morphological and chemotaxonomic characters. According to the results of 16S rDNA sequence alignment, strains B905, SMB11, SMB145, SF27, and DF14 show the highest sequence homology to the type strain of A. crystallopoietes (99.7%), and strain SN17, to the type strain of A. arilaitensis (99.8%). The isolated strains are capable of growing on naphthalene and phenanthrene (as the sole sources of carbon and energy) in the presence of 60 mg/l NaCl. Their cells contain large plasmids ranging in size from 85 to 130 kb. Plasmid elimination from Arthrobacter sp. SF27 has proved to result in the loss of capacity for growing on naphthalene and phenanthrene, suggesting a plasmid localization of genes responsible for degradation of these compounds.