On the population ecology of the gray plover in the northern Yamal Peninsula

The demography of the gray plover was studied using color banding at a stationary control plot in the northern Yamal tundra for seven years. Data on the dynamics of nesting density, fertility, breeding success, and site tenacity are presented. Cases of polygyny and the absence of nesting are described. Factors affecting population dynamics are discussed.     

The ecology of bilberry (Vaccinium myrtillus L.) and cowberry (Vaccinium vitis-idaea L.) in Western Siberia

The data on the ecology of bilberry and cowberry in the West Siberian Plain, Kuznetsk Ala Tau, and highland Altai are presented. Ecological ranges of these plants and amplitudes of their tolerance for some environmental factors are described.     

A system of Pleistocene refugia for Pinus sylvestris L. in the southern marginal part of the species range

An allozyme analysis of 67 Pinus sylvestris L. populations distributed over the entire species range has provided a basis for determining locations of 12 hypothetical Pleistocene refugia (HPRs) in its southern marginal part and estimating their relative contributions to the gene pools of seven phylogeographic population groups (PPGs) in the glaciated zone of the range. Using Nei’s (1978) minimum genetic distances (DN78 < 0.015) reflecting similarities and differences in allele frequencies between PPGs and the refugia, it has been shown that the main contributions to the P. sylvestris gene pool in Central Europe, Scandinavia, and the Russian Plain were probably made by the Balkan and Southern Ural refugia, and in Western and Central Siberia, by the Southern Ural, Turgai, and Southern Siberian mountain refugia.     

Daily Activity and Mobility of the Common Shrew (Sorex araneus L.)

Data on the daily activity and mobility of the common shrew (Sorex araneusL.) were obtained by the method of animal marking and recapturing in test plots. Sex- and age-related differences in the locomotor activity of animals were revealed, which depended on population size and the phase of the population cycle. Under natural conditions, animal activity in the daytime proved to decrease to a lesser extent than in captivity. The mobility (locomotor activity) of shrews was shown to depend on population density, reproductive rate, and weather.     

Dynamics of species and species complexes as a field of research in historical ecology

Specific features of research on the dynamics of species and species complexes are considered on the basis of data on Late Cenozoic subfossil and fossil bone remains. Special attention is given to the objects to be reconstructed, the principles of their classification, and the concept concerning three scales of these dynamics: the actual, historical, and evolutionary scales. Published in Russian in Ekologiya, 2006, No. 6, pp. 452–456. The text was submitted by the author in English.     

River Otter (Lutra lutra L.) in Northeastern Siberia: Distribution and Numbers

Russian Journal of Ecology -     

Long-Term Changes in the State of Gonads in Sea Urchins Strongylocentrotus intermediusfrom Amur Bay,the Sea of Japan

The state of gonads was analyzed in sea urchins Strongylocentrotus intermediuscollected in Amur Bay (Peter the Great Bay, the Sea of Japan) in August 1984, 1985, 1989, and 1997 at five stations: Skrebtsov Island (1), Sportivnaya Harbor (2), Cape Tokarevskii (3), Alekseev Bay on Popov Island (4), and Verkhovskii Islands (5). The first three stations were in the polluted inshore zone of Vladivostok; stations 4 and 5 were in the open (insular) part of the bay, remote from the main sources of pollution. The state of gonads of sea urchins collected in different years and areas strongly varied with respect to gonad index (GI), gonad maturity index, and indices of pathological changes in gonads. As compared with the data obtained in 1984, 1985, and 1989, the values of GI increased in sea urchins from stations 1–3 and decreased in sea urchins from stations 4 and 5. Although GI values were high, the indices of gonad maturity in animals from the coastal zone were very low. In general gonad maturity in sea urchins from the Amur Bay was lower in 1997 than in the previous years. The correlation analysis of long-term data revealed no positive correlation between the values of GI and gonad maturity index in sea urchins from stations 1–4. Histopathological changes were more serious in sea urchins from stations 1–3. In 1997, the indices of pathological changes in the gonads of sea urchins from the insular zone (stations 4 and 5) were higher than in the previous period (1984–1989). The influence of various ecological factors—temperature, salinity, environmental pollution, and food supply—on gametogenesis in sea urchins is discussed.     

Reproductive parameters and disturbances of embryonic development in the fieldfare (<Emphasis Type="Italic">Turdus pilaris</Emphasis> L.) in the zone of impact from the nuclear fuel industry

The impact of emissions from the Siberian Chemical Plant (Tomsk oblast) on reproduction and embryonic development of the fieldfare was studied. Bird abundance, clutch size, and egg volume in the impact and background (control) zones were similar, but partial brood mortality in the impact zone proved to be significantly higher, and the frequency of embryonic pathologies (including developmental abnormalities) was also several times higher than in the control.     

Body condition and reproductive characteristics of female water voles (Arvicola terrestris L.)

The relationship between long-term dynamics of reproductive parameters and body condition were studied in female water voles from a cycling population. Body condition was estimated from the deviation of body weight (excluding the weight of the uterus with embryos) from the theoretically expected weight calculated from the equation of body weight regression with respect to body length. As the index of body condition increases upon transition from decline to peak in the population cycle, the numbers of corpora lutea and live embryos also increase and the risk of resorption of the entire litter becomes lower.     

Population structure and dynamics of Monotarsobius curtipes (Myriapoda, Chilopoda) at the northern periphery of the species range

Studies on the population structure and dynamics of the stone centipede Monotarsobius curtipes C. Koch in soils of the northern Kola Peninsula have shown that, with respect to abundance and biomass, this species is a dominant of the soil macrofauna and, in particular, of the trophic group of zoophages. Life in high northern latitudes does not disturb the sex and age structure of populations but limits the reproductive activity of these centipedes. Specific biological features of M. curtipes at the northern periphery of its range include the absence of repeated breeding, completion of several developmental (age) stages within a short growing season, and long ontogeny involving several winterings.     

On the ecology and biology of invasive species Cyclachaena xanthiifolia (Nutt.) Fresen. in the Southern Urals and Cisural region

Ecological and biological characteristics of Cyclachaena xanthiifolia (Nutt.) Fresen., have been studied in four regions of the Southern Urals and Cisural region. Communities including this species have been attributed to association Ivetum xanthiifoliae Fija?kowski 1967 of the class Stellarietea mediae R.Tx., Lohmeyer et Preising 1950. It has been shown that ecological habitat conditions have a significant effect on the majority of morphometric parameters of C. xanthiifolia, accounting for 1.3 to 51.4% of their total variance. Seed production averages 6500 seeds per plant. Extensive dispersal of the species over the Southern Ural region is predicted.     

Some criteria for assessing the state and dynamics of sea otter (Enhydra lutris) populations in the Russian part of the species range

The state of sea otter populations has been assessed by a comparative method using criteria such as the density of equilibrium populations (on Medny and Iturup islands), food supply, and effects of certain external factors. Optimal values of population density for larger islands have been calculated using the Arcview GIS 3.3 program. For the inhabited water area (from the shoreline to the 50-m isobath), they range from 3.1 to 3.4 ind./km². The composition of sea otter diet and its changes on the Commander Islands, Kuril Islands, and southern Kamchatka are analyzed. The diameter of eaten sea urchins is considered as a parameter characterizing the degree of colonization of living space by sea otters. It is concluded that the abundance of these animals in the Russian part of the species range may slightly increase in the future due to the growth of their populations on the southern and middle Kurils.     

Analysis of Survival of the Red Fox (Vulpes vulpes L.) at the Phases of Population Growth and Decline

Changes in the survival parameters of the red fox were analyzed at different phases of the population cycle. It was found that the survival rate in all age classes, including newborns, drastically increased at the phase of population growth. The relationship between the general mortality rate and population size was determined. A hypothesis concerning the mechanism of these changes in the general mortality rate is suggested.     

Specific Features of the Population Ecology of Creeping Thistle, Cirsium arvense(L.) Scop. s. l.

Two populations of creeping thistle (Cirsium arvense) growing in a field uncultivated for many years and on the sloping bank of an artificial pond were studied with respect to the demographic and chemical composition. The results showed that the contents of some elements in plants depend on specific features of the soil and plant population parameters (abundance, biomass, and ontogenetic composition). Some indices of the content of mineral substances in the population and soil proved to be difficult to interpret unambiguously.     

State of the population of the European pearl mussel <Emphasis Type="Italic">Margaritifera margaritifera</Emphasis> (L.) (Mollusca,Margaritiferidae) at the northeastern boundary of its range (Solza River,White Sea Basin)

Only two river basins in which the European pearl mussel has survived to date are known in Arkhangelsk oblast. These are the Solza and Kozha basins. The northeastern boundary of the European range of this species passes along the watershed between the basins of the Solza and the Shirshema (the Onega Peninsula) and then along the Onega-Northern Dvina watershed. The population density and the proportion of juveniles widely vary in different parts of the Solza Basin, and, therefore, the previously conclusion concerning the ageing of the population in the Kazanka River (Bolotov and Semushin, 2003) applies only to certain parts of this river. The highest density of the pearl mussel in the Solza Basin is 68 ind./m². Fish cultivation contributes to the conservation of this pearl mussel population, as the release of Atlantic salmon juveniles ensures reproduction of the mollusk under conditions of regulated river flow.     

Population cycles of the bank vole in the range optimum

Patterns of seasonal and long-term dynamics of the size and structure of the bank vole population were studied in the European subtaiga subzone, the optimum of the species range. The dynamics of this population proved to undergo complex fluctuations with cyclic components, which have periods of one year and about three years. The one-year fluctuations of the population size and structure are accounted for by animal adaptation to seasonal changes in environmental factors. The fluctuations with the three-year quasi-period are determined by intrapopulation density-dependent mechanisms.     

A Method for Forecasting the Dates of Mass Calving and Some Characteristics of the Rut and Calving in the Kalmyk Population of Saiga (Saiga tatarica L.)

A method for forecasting the dates of calving in the saiga population on the basis of average fetal body weight is proposed. The method is based on the relationship between the number of days before calving and the average weight of fetuses, which obviates the necessity of determining fetal age and exact gestation period in this species. The average length of gestation, the dates of the rut in the years studied, and the age of females that have mated immediately upon the onset of the rut and before its cessation have been determined. It is shown that the duration of mass calving depends on the proportion of mature males in the population.     

Ecology of Nuclear Polyhedrosis Virus in Western Siberian Populations of the Gypsy Moth (<Emphasis Type="Italic">Lymantria dispar</Emphasis> L.)

The impact of the nuclear polyhedrosis virus on the population dynamics of the gypsy moth Lymantria dispar L. has been studied. The results have shown that polyhedrosis morbidity in the western Siberian population of the insect is relatively low, compared to that reported for North American and European populations. A possible cause of this situation is found in the high migration activity of moths in the Asian L. dispar populations, which allows the virus load on the biotope to remain relatively stable and insufficient for the initiation of mass viral diseases during population outbreaks.__________Translated from Ekologiya, No. 3, 2005, pp. 222–226.Original Russian Text Copyright © 2005 by Ilinykh.     

Reproductive parameters of <Emphasis Type="Italic">Lobaria pulmonaria</Emphasis> (L.) Hoffm. in the Urals

The capacity of species for expansion and colonization of new habitats is a key condition for the maintenance of their populations. In this study, specific features of the reproductive potential have been analyzed in Lobaria pulmonaria populations growing under contrasting climatic conditions. Certain ecological determinants governing the development of this lichen species have been revealed.