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Small Mammals in an Urban Area : Habitat Preferences and Urban-Rural Gradient in Nitra City, Slovakia

Klimant P., Klimantová A., Baláž I., Jakab I., Tulis F., Rybanský L., Vadel L., Krumpálová Z.

Polish Journal of Ecology

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2017

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Vol. 65, nr 1

144--157

EN

The small mammal species were investigated in the urbanized environment of Nitra city (Slovakia) in a multiscale-approach: at habitat level and at landscape level (urban-rural gradient). Continuous comprehensive rodent samplings from 2012 to 2015 were conducted in ten study sites, classified into three urban zones (landscape level). The total effort comprised 1,250 specimens of 13 species (Microtus arvalis, Apodemus sylvaticus, A. flavicollis, A. uralensis, Clethrionomys (Myodes) glareolus, M. subterraneus, Micromys minutes, Mus spicilegus, M. musculus, Crocidura suaveolens, C. leucodon, Sorex araneus, S. minutus) gathered in 14950 trapxnights. Environmental variables (habitat level) at each site were processed in the Geographical Information System as a proportion of landscape units around the trapping line and by a phytosociological survey. At the habitat level, we found a relationship between the landscape habitat structure and each species of small mammals. Diversity, species richness and relative abundance of small mammals decreased with the density of the built-up area. At landscape level, urban zones had a significant influence on species diversity, richness and relative abundance of small mammal populations. On the other hand, the presence of small mammal species precisely determined the urban zones, where we identified seven indicative species.

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The effects of urbanization small mammals communities in a gradient of human pressure in Warsaw city, Poland

Gortat T., Barkowska M., Gryczyńska-Siemiątkowska A., Pieniążek A., Kozakiewicz A., Kozakiewicz M.

Polish Journal of Ecology

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2014

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Vol. 62, nr 1

163--172

EN

The aim of this study was to determine the influence of human pressure and spatial structure of landscape on the occurrence of populations of small mammals in the environment of a large urban agglomeration. The investigations were carried out in Warsaw, Poland in 17 locations. The study sites were located on both sides of the Vistula River, of different landscape spatial structure, in various distances from the city center, and were subject to different degrees of human pressure. Part of the city located on the left bank of the Vistula River is more strongly transformed by man than the part located on the right bank of the river. A total of 933 specimens of 8 species of small mammals were caught using the live-trapping method (Catch-Mark-Release). The richest species composition was found at the city borders and in rural areas. On the left side of Vistula, the species diversity was lower than on the right side, showing significant negative correlation with the human pressure degree. Such pattern was not confirmed on the right side of the river. The only species to occur in all sites on the left side of Vistula was the striped field mouse (Apodemus agrarius). On the right side of Vistula, the striped field mouse was accompanied by the yellow-necked mouse (Apodemus flavicollis) in all research sites. The results indicate that the degree of human pressure and spatial isolation are crucial for composition of small mammal community. Less advanced urbanization processes in areas on the right bank of Vistula, as compared to districts on the left side, provide better contact between local populations of small mammals, and offer better living conditions to a large number of species, even in areas located in the center of the city.

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Methods for large scale assessment of small mammal abundance in open habitats : plateau pika (Ochotona curzoniae) in alpine grassland

Qu J., Li W., Yang M., Li K., Zhang Y.

Polish Journal of Ecology

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2011

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Vol. 59, nr 4

829-833

EN

Quick and accurate estimation of population density in large scale is required in both scientific studies and wildlife management programs. However, effective estimation of small mammal abundance is usually difficult and timeconsuming due to the body size and wide distribution of these animals. To test the efficiency of different methods in assessing small mammal densities, population dynamics of plateau pikas (Ochotona curzoniae, Hodgson) were studied from April 2005 to August 2009 in alpine grassland (Kobresia humilis) at a height of of 3846 m a.s.l. We compared the precision of walked transects method with mark-recapture method using Efford's maximum likelihood spatial estimator (ML). Significant positive correlation was found between walked transects and Efford's ML estimator (r[^2] = 0.58, P <0.001). The densities calculated with walked transects were about twice lower than those obtained using the mark-recapture method over the study period (i.e., summer). Nevertheless, the walked transects method remains useful for relative density estimation. Hence, the walked transects method is recommended for use as an index of relative density in large-scale assessment in alpine grassland where most small mammals are active and easily detected in an open habitat.

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Nest survival in a large river valley: an experiment using artificial nests on an island and bank of Vistula River (Poland)

Żmihorski M., Lewtak J., Brzeziński M., Romanowski J.

Polish Journal of Ecology

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2010

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Vol. 58, nr 1

197-203

EN

Predation pressure, which varies among habitats, is important factor for selection of nesting sites by birds. We investigated artificial nest depredation on an island 23 ha in size and on the river bank covered by willow-poplar forest and meadows in the middle Vistula river valley, in the spring and autumn 2006. We used polyurethane thrush-size nests placed at three heights (ground, bush and tree) with one quail egg. Each nest was checked twice, 7 and 14 days after the beginning of the experiment, in total 381 nest-inspections was included. Additionally, we live-trapped rodents (data from 510 trapnights included) which are potential predators of broods. We found that the survival rate of artificial nests was higher on the island as compared to the bank. Artificial nests placed on the ground revealed the higher survival rate than the nests placed on trees and bushes. Nest survival rate was higher in the autumn than in the spring. Repeatability of the results (survived vs. depredated) for the first and second 7-day period was high but lower on the island as compared to the bank. The abundance of rodents was higher on the bank during the spring, but no difference was recorded in the autumn. Rodents were also more abundant in the autumn than in the spring. This may indicate that survival rates of nests were not affected by rodents directly.

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The response of European pine marten (Martes martes L.) to the changes of small mammal abundance

Rosellini S., Barja I., Pineiro A.

Polish Journal of Ecology

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2008

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Vol. 56, nr 3

497-504

EN

The European pine marten (Martes martes) is commonly classified as an opportunistic predator. If this is the case, the species ought to show seasonal differences in the small mammal composition of its scats - the types of prey taken depending on their abundanc. In addition, it ought to consume the food that requires lower energy cost for their acquisition in each season. The feeding strategy of the European pine marten was studied in northwestern Spain by analyzing 209 scats collected between July 2004 and June 2005, and by seasonally trapping small mammals to obtain information on their abundance. The study area (5,722 ha) was located in a mountainous region (1,707.880 m a.s.l.) and covered with brushwood and deciduous forest (oak, birch, holly and pine). Molecular analysis of scats (PCR-RFLP) was performed to rule out the presence of the stone marten (Martes foina L.). The frequency of occurrence and biomass of the small mammals (the main prey species) preyed upon each season were compared. The pine marten consumed significantly more small mammals in the seasons in which their abundance was the lowest (winter and spring). In the autumn, when the highest number of small mammals was detected, the pine marten did not increase its predation of them. These results indicate that the European pine marten is not an opportunistic predator. Rather, the feeding strategy adopted by the species seems to be intermediate between that of an opportunist and specialist predator.

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Predation survival of ground nesting birds in grass and wheat fields: experiment with plasticine eggs and artificial nests

Purger J., Csuka S., Kurucz K.

Polish Journal of Ecology

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2008

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Vol. 56, nr 3

481-486

EN

There are no agricultural activities in Hungarian energy grass plantations (Elymus elongatus (Host) Runemark before harvesting in August, so the breeding success of the ground-nesting Common pheasant (Phasianus colchicus L.) and Common quail (Coturnix coturnix (L.)) is probably higher than in the neighbouring intensively managed grain fields. The dominant nest predators of these bird species (e.g. Red fox Vulpes vulpes L.) prey mostly on small mammals, thus the abundance of small mammals can influence the survival rates of ground-nesting birds. These assumptions were tested using artificial ground-nests and small mammal live traps in late May 2005. Of the nests, 25 were placed in the energy grass field which covered 60 ha and another 25 in the wheat field which area was 20 ha. Each of the nests contained one chicken egg, one quail egg and one plasticine dummy-egg. Real eggs were placed for the evaluation of nest predation rates and artificial plasticine eggs for predator identification from tooth and bill imprints. Following the placement of artificial nests, they were checked repeatedly between 16.00 and 18.00 every day. In both plots, 25 traps were set up, baited for 4 nights with quail egg and for another 4 nights with plasticine egg. Artificial nests lasted for 3 days in the wheat field and for 4 days in the energy grass field. The major predators in wheat were birds (16%) and mammals (84%), whereas in energy grass all predation (100%) was caused by mammals. There was no significant difference between types of predators in the two habitats. On-spot observations, traces and marks left on plasticine eggs, several droppings and the patterns of nest predation all suggested that the majority of nests were destroyed by Red fox. A significantly higher proportion of plasticine eggs were damaged in wheat (80%) than in energy grass (48%). Based on marks left on plasticine eggs, small mammal abundance was higher in wheat (80%) than in energy grass (33%), the latter habitat not yielding any small mammal captures at all. Traps in the wheat field caught significantly more small mammals with plasticine eggs (14) than with quail eggs (5). Plasticine eggs had greater attraction effect on small mammals, thus could negatively influence experiments with artificial ground nests.