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Novikov E.A., Petrovskii D.V., Kondratyuk E. Yu., Litvinova E.A., Moshkin M.P.
Signal effects of antigen challenge on foraging and agonistic behavior of intact conspecifics were studied in males of dwarf hamsters, Phodopus sungorus Pallas 1770, from laboratory stocks in different seasons of a year. Sheep red bloody cells (SRBC) administration was used as a model of antigen challenge. Control individuals were injected with a saline. In food choice tests, two feeding racks containing different olfactory stimuli (bedding of control males, bedding of SRBC-treated males, clean sawdust) were presented simultaneously to the intact males. In the summer season, the tested animals avoided to feed from the rack contained bedding of SRBC-treated males. In the winter season, olfactory stimuli had no effect on foraging behavior. The influence of antigen challenge on social behavior was estimated in pair-wise tests (SRBC-treated male on the peak of immune response vs. control male). In the summer tests, the SRBC-treated males showed more aggressive acts than the control ones. On the contrary, in winter, the SRBC-treated males were less aggressive and often displayed more submissive acts as compared to the control males. A similar interaction of the control and antigentreated males were found in summer tests for the animals that were derivate from audio-olfactory signals of the mature females. The avoidance of both direct and indirect contacts with SRBC-treated individuals seems to be an adaptive response to potentially infected conspecifics.
Tsikhon-Lukanina E.A., Nikolaeva G.G.
The body size and food composition of the barnacle Lepas anatifera L. were studied from cluster and single settlements. The capitulum is longer, mass and amount of consumed copepods are larger in individuals from cluster settlement. The differences between individuals from these settlements become greater with increasing the number of individuals in clusters probably due to a rise of turbulence accoompanying the formation of clusters.
Kukushkin O.V., Tsvelykh A.N.
The distribution, numbers, seasonal and diurnal activities, relation to temperature, biology and morphological features of the leopard snake, Elaphe situla, in the Crimea were investigated. The snake is distributed on the southern slopes and in western and eastern parts of the northern macroslope of the Crimean mountains and on the Geraklea peninsula up to an altitude of 680 m above sea level. It occurs permanently in populated areas, including cities (Sevastopol). The distribution of the snake is sporadic, but in habitats with optimal conditions, its population reaches 2.3-8.9 ind./ha. The number of males in the population 1.7 times exceeds that of females. The snakes are active from March to November at the temperatures of 16-29°C and 16-35°C in air and substrate, respectively. They occur in winter during thaw periods. The maximal activity of these snakes is observed in breeding periods. The way of life is day and night. The night activity is maximal in August. Pairing takes place in April-May; clutch, in June-July; molt, from March to November. The diet is represented by small mammals, birds, and lizards. Sexual dimorphism manifests itself in sizes, the number of ventral and supraucaudal shields, and the proportion between sizes of the skew field and tail. A relative size of the snake's head increases with age. The share of the Situla form is maximal (54%) in the central part of the snake's range. In peripheral areas of the range, the Leopardina forms predominate (84-85%).
Krasnov Yu. V., Gavrilo M.V., Chernook V.I.
The results of the aerial survey carried out in the Pechora Sea using AN-26BRL aircraft during 1997-1999 are presented. Twenty-three species of seabirds and waterfowl were recorded for the observation period, when the maximal water area was free of ice. The core species were seaducks with the dominance of the king eider and the black scoter. The overwhelming majority of the waterfowl occurs in the Pechora Sea while gathering and molting during migration. The native regional fauna of seabirds is poor and mainly represented by larids. In the northern part of the sea, there are significant food grounds for the Brunnich’s guillemots from colonies of the Novaya Zemlya. The avifauna in the Pechora Sea is characterized by high aggregations and their stable localization. The data on the density of the bird distribution in different parts of the area observed are given in tables. A map of mass concentrations of colonial seabirds, sea ducks, and swans in the Pechora Sea is given. Environmental factors affecting the formation of seasonal bird aggregations in the Pechora Sea are discussed, as well as the problems of marine bird conservation related to the development of oil extraction industry in the region.
The labrum of all the Culicomorpha studied is well-developed, being highly modified in Culicidae and Simuliidae due to its participation in blood-sucking. The outer wall of labrum is mostly sclerotized, except for Chironomidae and Simuliidae. The latter have the membranous outer wall. In Simuliidae and Culicoides (Ceratopogonidae) the labrum has a proximal apodeme located under clypeus. Except for Culicidae, all the culicomorph species studied possess a well-developed clypeo-labral muscle as well as the labro-epipharyngeal muscle fibers restricted to the labral base. Representatives of Culicidae, Chironomidae, Simuliidae, and Ceratopogonidae have also a clypeo-epipharyngeal muscle(s), which, in simuliids, plays a significant role during the mouthpart anchoring to the skin at the beginning of blood-sucking. All the culicomorph species investigated have an immovable sclerotized clypeus fused with the frons and genae. As a rule, its disto-lateral margins are thickened and join to the distal ends of lateral cibarial ridges. In Culicidae, this junction hypertrophies and forms a structure resembling the fulcrum of Brachycera-Cyclorrhapha. The epithelial clypeo-cibarial junction is absent in Culicomorpha. In most species studied, two paired muscles anchoring to the cibarial cornua were found.
Moskvitiva N.S., Kravchenko L.B., Mak V.V., Dobrotvorskii A.K., Panov V.V., Andreevskikh A.V., Moshkin M.P.
The variability of humor immune responsiveness of the field mice (Apodemus agrarius Pallas 1771) with respect to their age and reproductive status were studied in two urban populations. In both populations, sexual maturation of males and females resulted in a decrease of immune responsiveness. Despite the difference in the total population, the density-dependent regulation of sexual maturation in young individuals occurs in both populations studied. The humoral immune responses correlated positively with relative numbers of field mice.
The new data on morphometric characteristics, dispersal, and biotope preference of the Siberian mole Talpa (asioscalops) altaica Nikolsky 1883 in the Lena River valley (Yakutia) are provided. The species is shown to be quite common in the territory studied. The species prefers forest biotopes composed mainly of deciduous trees. In late summer, migration of the mole is well observed due to the dispersal of its juveniles.
Two new species of the genus Microphus Jurine 1807 (M. johni sp. n. and M. percitus sp. n.) are described from the Middle Volga River region (Nizhnii Novgorod oblast). Males of M. johni sp. n. were previously identified by N.F. de Andrade (1960) as M. albufeirae Andrade 1952. The discovery of their females makes possible to refer them to a new species.
Gulyaev V.D., Lykova K.A., Mel’nikova Yu. A., Bibik E.V.
The cestode Spasskylepis ovaluteri Schaldybin 1964, a valid species of the genus Spasskylepis ovaluteri Schaldybin 1964, from shrews (Sorex) of Siberia (northwestern Asia and Kamchatka) was redescribed, and its validity was restored. The first description of S. ovaluteri was made according to the type series that contains two different species of ditestolepidians: S. ovaluteri and Ditestolepis diaphana (Cholodkovski 1906) Soltys 1952. The S. ovaluteri name was left for hymenolepidideans with homonomous strobila separating single gravite proglottids with the equal rates of development of three testicles and vesicular juvenile uterus. As the type series was lost, the neotype S. ovaluteri was denoted from the type host Sorex araneus from the Kuznetskii Alatau. A new diagnosis of the genus Spasskylepis was formulated, as well as with its differential diagnosis.
The external morphology in 14 species of the genus Paramysis Czerniavsky 1882 dwelling in the Ponto-Caspian basin was studied, and subgenera to which the species belong are revised. The new supplementary parameters - morphological characteristics of mandibular palpus and penis - are proposed for the identification of the species. P. (P.) baeri, P. (P.) eyrylepis, and P. (P.) kessleri were incorporated into the genus Paramysis s. str. The validity of the subgenera Metamysis and Mesomysis is restored. The latter includes only P. (Mesomysis) intermedia. Four new subgenera are described: Nanoparamysis subgen. n. with P. (N.) loxolepis comb. n.; Serrapalpissis subgen. n. with P. (S.) incerta comb. n.; P. (S.) lacustris comb. n. and P. (S.) sowinskii, comb. n.; Longidentia subgen. n., which includes only P. (L.) kroeyeri comb. n.; and Occiparamysis subgen. n. with the single species P. (O.) agigensis comb. n.
Panov E.N., Nepomnyashchikh V.A., Rubtsov A.S.
A single uniterrupted phonogram obtained from the sedge warbler (Acrocephalus schoenobaenus L.) male has been analyzed with the use of statistical methods. The phonogram of 11.5-min duration contains 3626 syllables belonging to 42 typological variants. These syllables are united into 1032 homotypical sequences. Among syllable types three categories differing in respect of their acoustic parameters are distinguished. The rules of combining syllables during song production were revealed. The regime of singing appears to be devoid of stability. In the course of each bout of singing two principally different types of the syllable use take place: inertial and innovational ones. These types differ in the structural diversity and in respect of the rate of alternation of clusters composed of syllables with different acoustic characteristics. The singing behavior of this type can be regarded as a good example of self-organizing processes. The comparison of the song structure described with the phonograms (35.5 min in total) obtained from 9 other sedge warbler males from 6 different regions showed a high species-specific uniformity of both repertoires of syllable and rules of their combinations within lengthy song constructions. Possible mechanisms of control on the part of male over the generated sound sequences and the role of memory in this process are discussed.
The altitudinal distribution of 127 Orthoptera species in the Gissaro-Darvaz Mountains (Tajikistan) is analyzed based on original data. In these mountains, the species are distributed within absolute altitudes (up to 3500 m above sea level). The following groups of the insects were distinguished by the pattern of their vertical distribution: plain, mountain, and species widespread at all altitudinal levels. The altitudes for plain and mountain species are given, and their distribution along landscape-ecological profiles are discussed. The altitudinal faunistic complexes are distinguished, and boundaries between them are substantiated.
Khalaman V.V., Lesin P.A.
Aggregation of mussels (Mutilus edulis) was studied in different variants of laboratory experiments. This process was found to depend on the initial density of mollusks in a variant. Three main strategies of aggregation and colonization of substrates by mollusks were specified: (1) strategy of occupation of maximum area; (2) strategy of growing aggregates; (3) strategy of matrix. The importance of these strategies is discussed.
Naidenko S.V., Naidenko Sv. V., Clark L., Voznesenskaya V.V.
The reproductive success of laboratory rats (Rattus norvegicus) housed at different distances (2, 20, and 80 m) from a predator (Lynx lynx) was investigated. Virgin female (n = 120) and male (n = 40) rats of an outbred laboratory population were used for the experiments. Groups of rats (1 male and 3 females) were housed in standard cages in close proximity to the predator. Litter size, sex ratio, number of alive pups, number of placental scars and corpora lutea were counted; pre- and post-implantation losses were calculated for each female. The reproductive success of females calculated as a number of alive pups per female was much higher in both control groups (20 and 80 m) than in both test groups (2 and 2 m). Equal numbers of corpora lutea in all groups but different numbers of placental scars between the control and test groups indicated a higher pre-implantation loss in the experimental groups. The post-implantation loss was also higher in both test groups. The total loss (calculated as a difference between the number of corpora lutea and living pups) was twice as high as in experimental groups. Reproductive success of rats is related to the concentration/intensity was of predator's stimuli: when the concentration/intensity was higher, the number of live pups was less, and the total loss was higher.
Behavior and structure of social relations in family groups of the common vole Microtus arvalis Pall. were studied in laboratory. Four family groups consisting of 6-8 adult and subadult individuals (a total of 27) were observed in laboratory cages with an area of 1 m