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Populations of the forest dormouse (Dryomys nitedula Pallas, 1778) are widespread across Europe and south-western Asia, but their ability to survive in a mosaic of forest stands is insufficient, and they are extremely scarce in Russia. In 2013–2019, we studied the taxonomic and ecological composition of forest stands in the Middle Volga. Forest dormice were recorded in 30% of the investigated forest stands, being 4–70 ha in size. Habitats of the forest dormouse were characterized by higher species richness of woody plants, by presence of woody plant species with juicy fruits, dry fruits and seeds, and by dominance of shrubs (52.1% of all plant species). Out of 98 species of gymnosperms and angiosperms, species belonging to families Rosaceae and Salicaceae dominated. Out of the 98 registered plants, 43 species formed juicy and 55 species formed dry fruits and seeds, including Quercus robur L., Corylus avellana L., Tilia cordata Mill. Alien plant species (26.4%) had no impact on the habitat attractivity. Favorable conditions for existence the forest dormouse in the Middle Volga are secured by high diversity of woody plants in the forest stands, providing these animals with plant-based food. Usage of only optimal habitats resulted in patchy distribution of the species. [ABSTRACT FROM AUTHOR]

Associations between species of Laelapidae (Mesostigmata: Dermanyssoidea) mites and small rodents have been studied insufficiently. The aim of this study was to investigate infestation patterns of small rodent species by laelapid mites at six locations in Lithuania. A total of 728 rodents were snap- and live-trapped in various locations during 2013–2016. Eight rodent species were identified, namely Apodemus flavicollis, Apodemus agrarius, Myodes glareolus, Micromys minutus, Mus musculus, Microtus oeconomus, Microtus arvalis and Microtus agrestis. A total of 343 (47.1%) rodents were found to be infested with up to eight species of parasitic mites from the Laelapidae family (n = 1363): Laelaps agilis, Laelaps hilaris, Hyperlaelaps microti, Haemogamasus nidi, Haemogamasus hirsutus, Eulaelaps stabularis, Hirstionyssus sunci and Myonyssus gigas. The dominant species of mite found on rodents was L. agilis (89.1%), found on 43.4% of all hosts. Abundance and mean intensity of infestation with mites varied among species of hosts and were highest for A. flavicollis. We document new geographical and host records for gamasid mites of eight rodent species in Lithuania. [ABSTRACT FROM AUTHOR]

The dynamics of socio-spatial organisation are little investigated in dormice (Gliridae), a specific group among small mammals. During 2007–2017, 668 adult individuals were captured in a hazel dormouse (Muscardinus avellanarius) population in Lithuania, with the home ranges calculated for 134 males and 62 females. Over the study period, the abundance of the population gradually declined, and it was categorised into three groups: (1) high (1.2–1.4 adults/ha), (2) medium (0.9–1.0 adults/ha) and (3) low (0.4–0.7 adults/ha). When population abundance changed from high to low, the average sizes of home ranges increased from 1.4 ± 0.6 to 2.1 ± 1.2 ha in males and from 0.8 ± 0.5 to 1.1 ± 0.4 ha in females, while the total overlap of home ranges decreased from 57 ± 28 to 35 ± 23% in males and from 77 ± 27 to 44 ± 32% in females. Home ranges of marked individuals changed in consecutive years. In males, the average displacement of the centres of the home ranges was 58 ± 21 m, 75 ± 52 m and 73 ± 39 m at high, medium and low densities, respectively. The dynamics of the spatial relations in the investigated hazel dormouse population are consistent with the general tendency of home ranges to increase when population density decreases. However, the spatial organisation of population is more stable and potentially less related to the dynamics of food resources in comparison with other forest-dwelling small mammals. [ABSTRACT FROM AUTHOR]

We present morphometric and craniometric measurements of the herb field mouse (Apodemus uralensis) from Lithuania and analyze variation of body and skull size across species range. We suppose species is characterized by high size variability, not following Bergmann’s or Murphy’s rules. Preliminary, distinct size differences have been registered in the eastern and southern edges of the distribution range, with these populations having largest individuals according to average body and skull size. In terms of tail length and condylobasal length of the skull, Lithuanian mice on the north-western edge of the species range are among the largest, but in terms of body weight, body length, zygomatic skull width and the length of maxillary toothrow, adult A. uralensis from Lithuania are small and correspond to those from populations on the western edge of the range. The relative skull width (ratio of zygomatic skull width to condylobasal length) of Lithuanian A. uralensis is the smallest across the entire range. In A. uralensis from Lithuania, sex dimorphism is weakly expressed, with hind foot length and postorbital constriction larger in adult males, while the height of the mandibula and length of the mandibular diastema is larger in adult females. Juvenile and subadult A. uralensis from Lithuania differ in body weight, but not in size. [ABSTRACT FROM AUTHOR]

Using museum materials and recently trapped specimens of field voles (Microtus agrestis (Linnaeus, 1761)) from Lithuania and Estonia, we assessed temporal and latitudinal trends in body and skull size, comparing the periods 1980-1996 and 2014-2016. We measured four body and 23 skull characters, size-adjusting them using the geometric mean procedure. A pronounced decrease in the size of M. agrestis was noted in Estonia, where 23 out of 27 adjusted body and skull characters had decreased by up to 21.9%, with only the tail length, hind foot length, maximum height of mandibula excluding coronoid process and coronoid height of mandibula increasing significantly. Decreases were less marked in voles from Lithuania - most pronounced were a 6.1% decrease in adjusted body length, an 11.6% decrease in adjusted length of the braincase, a 3.85% decrease in the breadth of the braincase, measured at the widest part, a 2.9% decrease in condylobasal skull length and a 2.2% decrease in the height of the braincase. The coronoid height of the mandibula of Lithuanian individuals showed an 8.4% size increase. In both countries, the confounding effect of sex on the size changes of M. agrestis from 1980 to 2016 was much smaller than the effect of time period. Concluding, voles in Estonia became significantly smaller, while changes in the measured characters in Lithuania were heterogeneous. [ABSTRACT FROM AUTHOR]

Background: With farmland afforestation becoming common policy in many European Union countries, we studied how early forest succession (from meadow to young stand) influences small mammal species composition, diversity, abundance and biomass. Despite numerous investigations into forest succession, almost no attention has been given to the small mammal community change in the early-successional forest ecosystems, starting with the pre-forest habitat and ending with stand formation and the establishment of tree dominance. We compared small mammal communities in meadows at the initial stage of regrowth (with saplings less than 10 cm in height), in young forest (5-10 years old) and more advanced forest (15-20 years) in both cases of human-induced forest succession, where the trees had been planted, and natural forest succession, where natural regrowth of meadows had occurred. Results: The greatest diversity of small mammal species was recorded in the meadow ( H = 2.95), with a lower diversity found in the young forest ( H = 2.61) and even lower in the advanced forest ( H = 2.04), the last habitat being the most monodominantic. The order of species dominance from Microtus sp. ( M. arvalis, M. agrestis), Myodes glareolus, Apodemus flavicollis, Sorex araneus, A. agrarius in the meadow changed to M. glareolus, S. araneus, M. arvalis, M. agrestis in the young forest and to M. glareolus, A. flavicollis, S. araneus in the advanced forest. The lowest relative abundance of small mammals was recorded in the meadow (18.19 ± 2.27 ind. Per 100 trap-days), with Microtus voles being the most abundant. Relative abundance was higher in the young forest (22.72 ± 2.25 ind. Per 100 trap-days), with Myodes glareolus being the most abundant (7.59 ± 0.96 ind. Per 100 trap-days) and at its highest in the advanced forest (23.91 ± 2.77 ind. Per 100 trap-days), again with M. glareolus being the most abundant (15.54 ± 2.35 ind. Per 100 trap-days). Conclusions: Thus, our analysis suggests that that during early meadow-forest succession, the diversity of the small mammal community declines - the number of species decreases as typical meadow species are lost due to the transformation of the habitat and one or a few species became dominants. However, the relative abundance of the small mammals increases. Biological indices of small mammal communities differed between natural and human-induced meadow-forest succession. [ABSTRACT FROM AUTHOR]

By means of 845 questionnaires returned in 2009-2010, public attitudes towards the European bison were assessed in Central Lithuania. Free-ranging European bison have existed in this area for 40 years, inhabiting a suboptimal habitat characterized by intensive agriculture and fragmented forests. Despite 85.0 % of respondents reporting positive attitudes towards bison presence, 47.4 % of respondents considered the animals acceptable only if they were not closer than 10 km from their residence. Over 60 % of respondents suggested increasing the numbers of bison in the country, and 51 % suggested letting them live freely in the wild. The most negative attitude towards an increase in numbers was shown by women, respondents with lower knowledge of the species and inhabitants of biggest settlements. Public awareness relating to the European bison is lacking, as nearly 50 % of persons residing near areas inhabited by bison did not know about their presence. We conclude that, despite the high valuation placed upon the bison by the public and the ability of the bison to survive in open agrolandscapes with fragmented forests, negative public opinion may be a factor limiting the social carrying capacity for the species. Lithuanian human dimensions of this species should be taken into account when introducing the European bison elsewhere in Western Europe. [ABSTRACT FROM AUTHOR]

Owl pellets have high potential as a source of DNA. However, this noninvasive method of collecting DNA is rarely used, and its methodological aspects are poorly understood. We investigated the methodology for DNA extraction and amplification from owl pellets containing the smallest European rodent-the Harvest mouse Micromys minutus-as an example. We used mandibles identified in owl pellets for mitochondrial and nuclear DNA amplification. For DNA extraction, we tested two commercial protocols and utilized a protocol being a combination of two commercial kits which ensured high efficiency of DNA extraction. Additionally, we recorded that the amount of DNA was five times higher in extracts from teeth as compared to DNA extracts from jawbones derived from the same mandible. The quantity of DNA was significantly positively correlated with biological sample weight; however, the age of the pellet remains had an impact on the level of inhibition. We recorded inhibition in 40 % of mtDNA extracts derived from pellets older than 150 months, whereas in DNA extracts from pellets younger than 80 months, we did not observe a negative impact of inhibition on PCR efficiency. The amplification success rate was 89.9 % for the mitochondrial fragment and 39.4 % in the case of the nuclear fragment. We observed partial degradation of DNA evidenced by the fact that the longest fragments that we were able to amplify in the case of mtDNA were 450 and 200 bp for nuDNA. The study shows that pellets can be considered as a source of DNA and have high potential for molecular research in the case of threatened species and species that are difficult to study using standard field techniques. [ABSTRACT FROM AUTHOR]

Worldwide, Bartonella infections are known to inflict a wide range of mammals and, within rodents alone, more than 20 Bartonella species have been detected. There is, however, a lack of studies on the presence of Bartonella spp. in rodents in the Baltic region. We analysed 580 individuals belonging to eight small rodent species trapped in coastal and continental areas of Lithuania during 2015–2016. The presence of Bartonella DNA was examined by real-time PCR targeting the ssrA gene. The molecular characterization of the bacteria strains was based on sequence analysis of two housekeeping genes (rpoB, groEL) and the intergenic spacer region (ITS). For the rodents overall, the prevalence of Bartonella spp. was 54.8%, while the prevalence figures for each of the individual species were 8.3% in M. musculus, 15.8% in A. agrarius, 33.3% in M. arvalis, 42.4% in M. glareolus, 53.4% in M. oeconomus, 57.5% in M. minutus, 79.6% in A. flavicollis to 80% in M. agrestis. Sequence analysis revealed that the Bartonella strains belonged to the B. grahamii, B. taylorii, B. rochalimae, B. tribocorum, B. coopersplainsensis and B. doshiae genogroups. The highest Bartonella infection rates and the highest species diversity were both detected in rodents captured in the coastal area. To our knowledge, these are the first reports of the presence of B. coopersplainsensis, B. doshiae and B. tribocorum in Lithuania. [ABSTRACT FROM AUTHOR]