Naidenko S.V., Erofeeva M.N., Demina T.S., Alekseicheva I.A., Pavlova E.V.
Pallas’ cat inhabits dry steppes in the center of Asia where winter temperatures may drop below -50°C. We suggested that the evolution in severe climatic conditions and costly adaptations to low ambient temperatures may result in decrease of immunity of this species, because it prevents acquisition of adequate resources to develop robust immune responses. We estimated humoral immune response to a non-replicating antigen (sheep red blood cells) in ten captive Pallas’ cats, twelve domestic cats and six Far Eastern wildcats. Blood-sampling was conducted prior to and 21 days after the injection. We analyzed changes in body mass, number of leukocytes, IgG concentration and hemoagglutination/hemolysis titer. Pallas’ cat had lower hemoagglutination/hemolysis titer before the injection and showed lower titer than the two other felids three weeks after the injection. These results may reflect a lower level of natural antibodies in Pallas’ cat than in the two other species and, possibly, lower innate immunity of this species. Domestic cats, which were serum positive to feline coronavirus, also showed lower hemoagglutination/hemolysis titer during the experiment than serum negative animals.
Puzachenko A.Yu., Masuda R., Abramov A.V.
A morphometric variation in 23 characters of 77 skulls of the Altai weasel Mustela altaica from the delta of Ili River in Kazakhstan has been analysed. Multivariate analyses (nonmetric multidimensional scaling and multivariate allometry) were used to estimate a sexual size dimorphism (SSD) in cranial characters. A high degree of the sexual dimorphism was found in the Altai weasel population. All morphometric characters in the males were larger than those in the females. An average sexual size dimorphism (ASSD) of M. altaica lies within the genus Mustela range. In this species, the SSD is a result of differences in the scale and allometry of cranial characters between sexes, reflecting the differences in male/female allometric ontogenetic patterns. The results are discussed in relation to the existing hypotheses on sexual dimorphism in the mustelids: food competition, sexual selection, and differences in reproductive strategies.
Alekseeva Ya.I., Shpak O.V., Gorbunov S.S.
The work is based on an analysis of archival documents containing quantitative information on harvests of beluga whales in the White, Barents, and western Kara seas from 1930. Also, information is provided on the possible places where the documents containing data of beluga whaling could still be preserved. The probable causes of the reduction in catches and abundance of beluga whales in the coastal waters of the study areas, observed from the late 1960s, are discussed.
Vekhnik V.A., Vekhnik V.P., Rozentsvet O.A., Bogdanova E.S.
Some species of mammals can reproduce in anticipation of future food abundance based on different ecological mechanisms. During 2017–2018 we studied the reproduction of a common abundant species, the yellow-necked mouse Sylvaemus flavicollis, in oak communities during the maturation of acorns to determine if the timing of reproduction has a predictive character. We observed a moderate yield oak year and a high yield oak year. At the very beginning of acorn growth, the share of females in oestrus was maximal, and no pregnant females were found. During the maturation of acorns, the proportion of females in oestrus gradually decreased. The share of males with reproductive activity also decreased during the census. In 2018, the sexual activity of the males was considerably higher than that in 2017, what can point on its role in the regulation of the intensity of reproduction. Thus, we found that mating and pregnancy in a large proportion of the mice during the autumn peak of reproduction, began at the beginning of acorn ripening, due to females feeding on immature seeds during pregnancy and lactation, eliminating a delay between forage yield and rodent reproduction. By the time the acorns were completely ripe and fell, the most of juveniles became independent, and a portion of the young females became sexually mature. So, the dependency of reproduction from the flow of acorns maturation was revealed instead of any prediction. A possible reason for this synchronization is the composition of the diet and, in particular, the contents of lipids and fatty acids. During the maturation of acorns, the proportion of triacylglycerols, the main constituents of body fat in animals, increases considerably, which can increase the survival rate of juveniles.
Bachura O.P., Kosintsev P.A., Lobanova T.V.
Changes in Late Holocene species composition and dynamics of number of large mammal fauna are described for the forest-tundra zone of West Siberia. The review is based on 14C dated materials from cave and archeological sites. During the studied period the species composition of large mammals was nearly constant and similar to the modern one with azonal species dominating in the fauna. The faunal composition of the southern part of forest-tundra zone differed from the northern part by the presence of the beaver and otter. Minor changes in the faunal composition took place only in the northern part of this area at the end of the Subatlantic period and concerned changes in the northern boundary of the sable range. It was controlled by the shift of northern forest boundary and the increased human activities. People completely exterminated beavers and sables in the region by the mid 18th century. The mountain hare, polar fox, and reindeer had persistently high numbers during the Late Holocene in the forest-tundra zone. The numbers of other species were low. The modern mammal species composition of the forest-tundra zone was formed by the interplay of climatic change and commercial activity of people.
Borzée A., Yi Y., Andersen D., Kim K., Moon K.-S., Kim J.-J., Kim T.-W., Jang Y.
Once reaching maturity, individuals of most mammal species typically disperse towards suitable habitats, adequate to their ecological requirements. If the habitat has reached saturation for carrying capacity, these individuals may disperse further to find adequate habitat. The Asiatic black bear (Ursus thibetanus) has been reintroduced on the Korean Peninsula since the early 2000s, and is now considered successfully reintroduced. The population size in the Jiri Mountain National Park, where the species has been reintroduced, has reached about 56 individuals, and for the first time a young male has dispersed a significant distance outside of the national park. The individual was caught and released within its home range before dispersing again. Our research highlights the dispersal pathway followed by the individual, the landscapes crossed, and the public reaction to this dispersal event.
Voyta L.L., Golenishchev F.N., Petrova E.A.
All available information on the small mammal collection from the collecting point Tongjia Yingzi of the Khingan expedition in 1891 under the leadership by Dmitry V. Putjata is presented. Also, the geographic position of this point is clarified. The collection is kept at the Zoological Institute of the Russian Academy of Sciences (St. Petersburg, Russia) and, at present, contains 17 specimens from Tongjia Yingzi of Putjata's Khingan collection; these belong to Lipotyphla, Chiroptera, and Rodentia.