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Start Over Creator Sedláček, František

2. Barrier effects of roads on movements of small mammals

Creator:
Rico, Adriana, Kindlmann, Pavel, and Sedláček, František
Type:
article and TEXT
Subject:
Apodemus flavicollis, Clethrionomys glareolus, habitat fragmentation, linear clearings, road barriers, road crossing rates, and Sorex araneus
Language:
English
Description:
Roads and highways represent one of the most important anthropogenic impacts on natural areas and contribute to habitat fragmentation, because they are linear features that can inhibit animal movement, thereby causing barrier effects by subdividing the populations adjacent to the roads. The study presented here aims to determine, to which extent roads act as a barrier, subdividing populations of three species of small forest mammals: bank vole, yellow-necked mouse and common shrew, and what is the relative importance of road width and traffic intensity on the barrier effect. The study was carried out at four 25 m long segments of roads, close to the city of České Budějovice. All segments crossed a forest. The capture-recapture method was applied to determine the crossing rates of animals. The traps were checked three times each day during four consecutive nights, in summer and in autumn. We found that: (1) roads strongly prevent crossing movements in all three studied species, (2) there are interspecific differences in road crossing rates, (3) species cross more often narrow than wide roads, (4) traffic intensity does not affect the crossing rates.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/

5. Coprophagy in Brandt's vole (Microtus brandti) from the Inner Mongolian grasslands

Creator:
Pei, Yan-Xin, Wang, De-Hua, Wand, Zu-Wang, Zima, Jan, Griffiths, Huw I., Burda, Hynek, and Sedláček, František
Type:
article and TEXT
Subject:
Brandt's vole, Microtus brandti, and coprophagy
Language:
English
Description:
We studied coprophagous behaviour in Brandt's vole using a solute food marker (Co-EDTA). Examination of marker concentrations in the stomach, small intestine, caecum and colon of voles killed at half-hour intervals after a pulse dose of Co-EDTA indicated that the marker was recycled to the stomach by coprophagy. Recycling of digesta via coprophagy enables Brandt's vole to utilise diets of higher fibre contents. This is the first evidence for coprphagy in this species.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/

6. distribution and breeding seasons of the dassie-rat, Petromus typicus (Petromuridae, Rodentia)

Creator:
Coetzee, Cornelius G., Zima, Jan, Griffiths, Huw I., Burda, Hynek, and Sedláček, František
Type:
article and TEXT
Subject:
desert adaptation, macroclimate, fecundity, embryos, placental scars, and tooth wear
Language:
English
Description:
The diurnal dassie-rat, Petromus typicus, occurs in the mountainous areas along the eastern side of the Namib Desert, as well as and on inselbergs in the Namib with an annual mean rainfall >25 mm. Its distribution is limited by the presence of either moist woodlands or to areas with cold, wet winters. The gestation period is taken as three months, based on the precocial condition of the young at birth. A maximum of three young per litter was recorded, with two being the mode. The young start taking solid food at 14 days and wean at about three weeks, then attaining adulthood at about nine months (at a mass of ca. 150 g). The two main breeding seasons could be related to the onset of the rainy season, although it cannot be ruled out that breeding in endogenous.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/

7. Eimeria burdai sp. n. (Apicomplexa: Eimeriidae), a new parasite species from subterranean African silvery mole-rat, Heliophobius argenteocinereus

Creator:
Koudela, Břetislav, Šumbera, Radim, and Sedláček, František
Format:
print
Type:
model:internalpart and TEXT
Subject:
Apicomplexa, Eimeriidae, Eimeria burdai, Rodontia, Bathyergidae, and Heliophobius argenteocinereus
Language:
English
Description:
A new coccidian parasite of the genus Eimeria Schneider, 1875 is described from the subterranean African silvery mole-rat Heliophobius argenteocinereus Peters, 1846. Oocysts of Eimeria burdai sp. n. were subspherical to broadly ellipsoidal 17.8 (16-19) x 14.1 (12-15), with ashape index 1.2 (1.1-1.4). Oocyst wall was bilayered, smooth and colourless, approximately 1.0 thick. Outer layer was significantly thicker than inner one. A micropyle and oocyst residuum were absent. One or two ellipsoidal or spherical polar granules were present. Sporocysts were ellipsoidal, 10.8 (9-12) x 6.2 (5-8) with a shape index 1.7 (1.5-1.9). Sporocyst wall was single-layered, thin, smooth and colourless, with small Sticda body at the pointed end. In freshly sporulated oocysts, spherical sporocyst residuum was composed of small granules enclosed by a thin membrane. Sporozoites were elongate, lying length-wise in the long axis of the sporocyst, partially curled around each other, with single large refractile body located posteriorly. Faintly distinguishable nucleus was in the central part of the sporozoite. This eimerian represents the first coccidian species described from subterranean African silvery mole-rat (Rodentia: Bathyergidae).
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

8. Epigenetic and morphometric divergence among black rat, Rattus rattus, populations on Western European islands

Creator:
Sousa, Inês Pereira de, Quartau, José Alberto, Mathias, Maria da Luz, Zima, Jan, Griffiths, Huw I., Burda, Hynek, and Sedláček, František
Type:
article and TEXT
Subject:
insularity, differentiation and variability, and colonisation
Language:
English
Description:
Over the decades, islands have provided a useful background for the evaluation of the consequences of isolation upon populations. Epigenetic and morphometric divergence among black rat (Rattus rattus) populations from Western European island (São Miguel, Terceira, Flores, Porto Santo, Berlenga, Corsica) were analysed and compared with mainland reference populations (Portugal, France, Morocco). Neither of the two approaches showed insular samples to have greater distinctiveness than those from the mainland. The overall pictures of epigenetic and morphometric similarity among populations were concordant, apparently in agreement with their probable origin from founder individuals brought by former maritime traffic. Mainland populations were more variable, but only according to morphometric characters. The adaptive and evolutionary significance of the patterns found may be related to both the period of population isolation and island area.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/

9. First results of beaver (Castor fiber) reintroduction in Volga-Kama National Nature Zapovednik (Russia)

Creator:
Gorshkov, Yurii A., Gorshkov, Dmitry Y., Easter-Pilcher, Andrea L., Pilcher, Brian K., Zima, Jan, Griffiths, Huw I., Burda, Hynek, and Sedláček, František
Type:
article and TEXT
Subject:
feeding behaviour, home range size, radiotelemetry, food preference, and dispersal after reintroduction
Language:
English
Description:
The main reason for reitroducing beavers (Castor fiber) to the Raifa part of the Voga-Kama National Nature Zapovednik (VKNNZ) was to utilise their habitat-changing activities - primarily the use of their ability to build dams - to stop the degradation of the Zapovednik hydrosystem (Gorshkov et al. 1999). Today there are seven beaver dams on the rivers that run through the Zapovednik. We studied the movements of the beavers by locating new cuts, dens, trails, dams, etc. and by radiotelemetry. We assumed that in the first phase of reintroduction the spatial structure of the beaver subpopulation consisted of four permanent and five temporary settlements. We determined the home ranges of the reintroduced beavers as being approximately seven ha, plus smaller additional patches of habitat that were used during the witner. Another object of our investigation - the feeding behaviour of reintroduced beavers - showed that the most preferred tree genera were aspen and willows, followed by alder and birch. The wolume of trees cut by beavers between autumn 1996 and spring 1999 in the Volga-kama National Nature Zapovednik was 11.69 m3
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/

10. Food selection of Microtus agrestic in air-pollution affected clearings in the Beskydy Mts, Czech Republic

Creator:
Heroldová, Marta, Zima, Jan, Griffiths, Huw I., Burda, Hynek, and Sedláček, František
Type:
article and TEXT
Subject:
field vole, diet, air pollution clearings, and impact on forest regeneration
Language:
English
Description:
The small mammal community of an air pollution affected area of the Beskydy Mts was studied over a seven-year period. Highest dominance and population density values were found in the field vole (Microtus agrestis) and its feeding ecology and negative impact on reforestation have been evaluated. The vegetative parts of plants, particularly those of monocotyledons, were dominant in vole diets, mainly as the area is largely occupied by the invasive plant genus Calamagrostis. In early spring (i.e. before the growing season started) grasses predominated in the field vole's food (74 % of volume, v). Bark was also consumed to some extent - its importance index value (I) was 4 %. In spring (i.e. after the growing season started) grasslike species were again preferred (v = 57 %) but flowers of Vaccinium myrtillus were also consumed (v = 20 %). Even in autumn grasslike species prevailed (v = 36 %), however, the diet was more diverse and seeds and fruits (v = 30 %) were also eaten. of these the basic food items were those of V. myrtillus (v = 16 %) and of herbs and ferns (v = 16 %) including Oxalis acetosella (v = 14 %). An increase in fungi in the diet was found in autumn. Diet availability and early spring and spring diets ere highly correlated, but this was not the case in autumn. The extent of vole damage to tree regeneration in 3,027 saplings was studied. The frequency of damage was significantly greater in deciduous tree species (15 %). Coniferous tree transplants were attacked only rarely (1.4 %), and usually when the tree was already in poor condition. The greater degree of damage caused to natural and artificial forest regenetarion can only be associated with high vole population densities.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/