Current condition of populations and spatial-environmental features of habitats of russet ground squirrel Spermophilus major

The russet ground squirrel (Spermophilus major ) is known in the literature as a numerous widespread ground squirrel species. In recent decades, a decline in its abundance was found in some parts of its range. We have assessed the condition of this species in most parts of its distribution area based on our observations and interviews with local people. Spatial, landscape and vegetation cover parameters of S. major settlements have been studied. The research results showed a decline in the number, disappearance of settlements and a decrease in suitable habitats for this species. Small and medium-sized settlements with relatively low density of burrows, associated with low grass meadow communities typical for pastures and cattle grazing, prevail among the found settlements. One of the main factors for the decline in the number and disappearance of settlements of russet ground squirrel is, apparently, a decrease of pasture cattle grazing intensity. The continuing trend of degradation of pasture ecosystems may pose a threat to the existence of this species.

Seasonal Changes in the Distinct Taxonomy and Function of the Gut Microbiota in the Wild Ground Squirrel (Spermophilus dauricus)

Seasonal breeding is a normal phenomenon in which animals adapt to natural selection and reproduce only in specific seasons. Large studies have reported that the gut microbiota is closely related to reproduction. The purpose of this study was to explore the distinct taxonomy and function of the gut microbiota in the breeding and non-breeding seasons of the wild ground squirrel (Spermophilus dauricus). The 16S rRNA gene sequencing technology was utilized to sequence the gut microbiota of the wild ground squirrel. PICRUSt analysis was also applied to predict the function of the gut microbiota. The results suggested that the main components of the gut microbiota in all samples were Firmicutes (61.8%), Bacteroidetes (32.4%), and Proteobacteria (3.7%). Microbial community composition analyses revealed significant differences between the breeding and non-breeding seasons. At the genus level, Alistipes, Mycoplasma, Anaerotruncus, and Odoribacter were more abundant in the non-breeding season, while Blautia and Streptococcus were more abundant in the breeding season. The results of a functional prediction suggested that the relative abundance of functional categories that were related to lipid metabolism, carbohydrate metabolism, and nucleotide metabolism increased in the breeding season. The relative abundance of energy metabolism, transcription, and signal transduction increased in the non-breeding season. Overall, this study found differences in the taxonomy and function of the gut microbiota of the wild ground squirrel between the breeding and non-breeding seasons, and laid the foundation for further studies on the relationship between the gut microbiota and seasonal breeding.

ECOLOGICAL FEATURES OF HIBERNATING ANIMALS OF YAKUTIA

Under the influence of environmental factors, in winter-sleeping animals living in extreme winter conditions, a wide range of mechanisms of ecological and physiological adaptations is mani-fested that ensure the normal course of wintering and the survival of populations of species after its end. We carried out an analysis of our own data and literary sources on ecology and endoparasite infestation in three species of rodents – black-capped marmot, Asian long-tailed ground squirrel, Siberian (Asian) chipmunk, and in a representative of predators– brown bear. Data on the distribu-tion of the listed species of hibernating animals in the territory of Yakutia, their reproduction, nutri-tion, the extent of infestation by helminths, hibernation, time of bedding and awakening are given. Before going into hibernation, all hibernating animals reduce their diet and resort to hunger strikes. During this period, liquid and solid excrement is excreted from the body and, together with food waste, helminths leave or destrobilatethe gastrointestinal tract.

Richardson’s ground squirrels (Urocitellus richardsonii) are associated primarily with intermediate levels of grassland, clay loam soils, and human development in Canadian mixed-grass prairies

Richardson’s ground squirrel (Urocitellus richardsonii, Sabine 1822) is a widespread burrowing mammal on the Northern Great Plains. This species is a prominent prey item for a variety of predators, and its burrows provide important habitat for other wildlife; however, Richardson’s ground squirrel is also considered an economically damaging agricultural pest. Despite the ecological importance of Richardson’s ground squirrels and their status as pests, there are gaps in our knowledge about large-scale habitat associations for this species. In 2011 and 2012, we conducted 1840 road-side surveys in a 130,000-km2 area of southern Saskatchewan, Canada to understand which habitat features are associated with Richardson’s ground squirrel occurrence. Ground squirrels were observed on 8% of the surveys. Probability of ground squirrel occurrence was highest in areas with moderate amounts of grassland (approximately 30%), areas that were developed by humans (>30%), and had a high proportion of clay loam soils, presumably for burrowing. Our study highlights the importance of heterogeneous landscapes and that areas disturbed by humans may provide suitable vegetation structure for ground squirrels. This information can help to identify important habitat for species that rely on Richardson’s ground squirrels and identify areas where Richardson’s ground squirrels could come into conflict with agriculture.