Abundances of the common hamster in western Europe declined dramatically over the last 30 years. Recently, severe restrictions in distribution range have also been reported from central European countries. Here we update knowledge of the hamster distribution range in the Czech Republic based on information from six independent sources: (1) monitoring programme for the common vole carried out by State Phytosanitary Administration, (2) monitoring carried out directly by us, (3) questionnaire data from farming companies, (4) questionnaire data from district museums, (5) data from a public server BioLib for mapping species distribution, and (6) observations from nonrelated research activities and persons taking interest in hamsters. The comparison of locations detected after 2000 with those from the last survey > 30 years ago suggests that the range is severely reduced with hamsters retreating to the optimum lowland habitats along large rivers. These results suggest that the demographic mechanisms causing population decline in western populations operate in central Europe as well.
Small mammals are just as likely to become extinct as larger species, although the latter receive disproportionate attention with respect to conservation activity and research. We focused on rarity, vulnerability to extinction and conservation status for small terrestrial mammals from the orders Soricomorpha and Rodentia occurring in the Balkans and Anatolia. Although these two regions have fewer mammalian species than Central Europe in very small biota areas (surface areas 4 km2), they accumulate species at a much faster rate with increases in surface area. The distribution ranges of fifteen species from a total of 88 (= 17%) are confined to this studied area, with eight species being endemic to Anatolia and six to the Balkans. High endemism is indicative of small ranges, i.e. of one form of rarity of Rabinowitz’s ‘seven forms of rarity’ model. The ranges of at least three species (Talpa davidiana, Myomimus roachi and Dinaromys bogdanovi) have declined since the Last Glacial Maximum. Although numbers of extinctions correlates strongly with the number of endemics, and species displaying both restricted distribution and low density are those most at risk of extinction, very little conservation activity and research is focused on small-range endemics.
everal primer sets were described for PCR amplification of the Sry gene that became very suitable method for sex identification in mammals. We tested applicability of two primer sets for sex identification in one bat and 12 rodent species from Central Europe. Rapid DNA extraction with non-ionic detergents, which is very suitable for large-scale population studies, was used. Primers SRY-A from Pomp et al. (1995) did not amplify Sry fragment in males of Myotis myotis, four species of Microtus, and Clethrionomys glareolus, while amplification was successful in four species of Apodemus, two species of Mus, and Sciurus vulgaris. On the other hand, primers from Sánchez et al. (1996) gave clear Sry band in males of all tested species, only with one exception, i.e. male of Sciurus vulgaris.
Microtus tatricus occurs in the Carpathian Mountains of Slovakia, Poland, Ukraine and Romania – a list of current distribution records is given. The species’ distribution range is insular on the scale of its entire distribution and fragmented within each mountain range inhabited. The overall altitudinal range is 650–2350 m a.s.l., with the largest number of collecting sites situated between 1100–1700 m a.s.l. The total range size of M. tatricus was estimated as 840 km2 and the total population size at between 200,000–250,000 individuals. A possible reduction in the species’ distribution range is discussed.
Different chromosomal races of the Nannospalax ehrenbergi (Nehring, 1898) complex inhabit south-eastern Turkey. In spite of the fairly restricted range of this mole rat in Turkey, no less than eight different karyotypes have been reported so far. These differ in diploid number (range from 52 to 58), fundamental number of chromosomal arms (ranging between 72 and 90) and in the fundamental number of autosomal arms (ranging from 68 to 86). The most common chromosomal form is 2n = 52, NF = 76, NFa = 72, which is known from Southeast Anatolia. In this paper I report on a new N. ehrenbergi karyotype from south-eastern Turkey. In 18 specimens investigated, the diploid number of chromosomes was 2n = 56, NF = 66, and NFa = 62. The karyotype consisted of 4 pairs of metacentrics/submetacentrics and 23 pairs of acrocentrics. The X chromosome was medium-sized submetacentric and the Y chromosome was small acrocentric. This chromosomal set is different to the most common Turkish N. ehrenbergi karyotype (2n = 52) and also differs markedly from the known chromosomal forms from Gaziantep (2n = 56, NF = 82, NFa = 78) and Tarsus (2n = 56, NF = 72, NFa = 68 ).
The taxonomy and distribution of rodents in Zambia was comprehensively summarized in 1978 by W.F.H. Ansell in his excellent book Mammals of Zambia. Despite the fact that during the last three decades many new taxonomic revisions of African rodents were published and extensive new material collected, not much work has been done on Zambian rodents since the book publication. Here we summarize the current knowledge of one of the most speciose group of African rodents, the tribe Praomyini, in Zambia. We review available historical records and revise our recently collected material by sequencing the mitochondrial DNA gene of cytochrome b. The presence of eight species of Praomyini in Zambia is documented and the pattern of their geographical distribution is described and discussed. Two species, Praomys minor and Mastomys coucha, are reported for the first time from Zambia and Praomys cf. jacksoni probably represents a new undescribed species. On the other hand, the actual occurrence of Colomys goslingi, known in Zambia only from one historical record, is questionable. The results document the usefulness of the DNA barcoding approach for description of species diversity of taxonomically complicated groups with many cryptic species.
A study was conducted in Mabira Central Forest Reserve in Uganda to determine rodent species composition, relative abundance, and habitat association. A total of 1,030 rodents belonging to 14 species were captured on 10,584 trap nights. Rodent species recorded include: Lophuromys stanleyi, Hylomyscus stella, Praomys jacksoni, Mastomys natalensis, Lophuromys ansorgei, Lemniscomys striatus, Aethomys hindei, Mus triton, Mus minutoides, Deomys ferrugineus, Gerbilliscus kempi, Rattus rattus, Grammomys kuru, and Hybomys univittatus. Overall, L. stanleyi (23.7%) was the most dominant species followed by H. stella, P. jacksoni, and M. natalensis. Species richness and evenness was highest in the regenerating forest habitat and least in the intact forest habitat. Rodent abundance was significantly affected by habitat type. The regenerating forest habitat had the highest number of animals, while the lowest numbers were observed in the depleted forest habitat. Species diversity was higher in regenerating forest habitat and lowest in the intact forest. The three habitats appeared distinct in terms of rodent species composition and there was a strong association between the two trapping grids in the same habitat type. All ordination plots showed that different rodent species consistently associated with distinct habitats. Habitat type and seasonal changes influenced rodent composition, relative abundance and habitat association. Composition of rodent community reflected the level of habitat degradation and can be used as a proxy for evaluating the biodiversity of lowland tropical forests.
Key adaptations enabling mammals to cope with oxygen deficiency at high elevations relate to oxygen transfer into the blood. Among others, the efficiency of this mechanism depends on haematocrit (Hct, the volumetric fraction of red blood cells in blood). Although blood of high-elevation mammals is usually characterised by normal or slightly increased Hct, there are contradictory findings from studies along different elevational gradients. The aim of this study was to explore variability of Hct at both inter- and intraspecific levels in six rodent species from lower and higher elevations of Choke Mountain in Ethiopia. We found that Stenocephalemys sp. A from higher elevation had higher Hct than its congener Stenocephalemys albipes from lower elevation and a similar but weaker tendency was observed intraspecifically in Lophuromys simensis. Furthermore, Hct among four species occupying the high-elevation Afroalpine zone was comparable, and higher than in animals from lower elevations. Higher Hct in the three Afroalpine specialists probably contributes to local adaptations for life in high elevation environments under hypobaric hypoxia.