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-Werka J. 1990. Estimation of roe deer density based on the abundance and rate of disappearance of their faeces from the forest. Acta theriol. 35: 111-120.Population density of roe deer Capreolus capreolus (Linnaeus. 1758) was assessed in a small forest (about 200 ha) surrounded with fields. The method used was based on known amounts of roe deer faeces in the forest and their rate of disappearance. Faeces disappearance was exponential, and the average time of their persistence on the forest floor was 26 days in summer. 70 in spring, and 118 in autumn. The faeces disappearance rate was significantly affected by weather conditions (air temperature, amount of rainfall, number of rainy days), as well as by the activity of coprophages. Estimations of roe deer density by driving the animals about the forest, and by assessing the quantity of faeces gave similar results.

It as known that the species is not only the commonest, but also the most widely spread in town, of all the urban rodent community, occurring in 55% of the study areas. By means of a 0-10 point scale, proposed here, all the areas were classified in respect of 5 criteria: size of area, size of complex in which the area is included, distance from town boundaries, shelters and »quietness«. It was found that the most important factor for A. agrarius in urban green areas is a sufficient amount of shelters; and the »distance« is the least important one, since the rodents also occur in the city district. The habitat requirements of A. agrarius in town are discussed.[Res. Inst. Environ. Develop., Krzywickiego 9, 02-078 Warszawa, Poland].

The sizes of home ranges and population density in Clethrionomys glareolus (Schreber, 1780) have been determined in a 5-day period by use of a trap line consisting of 80 sites (2 traps per site) spaced every 15 metres. Three days prior to, and during the trapping period oat grain was offered in sets of 4 plastic boxes set in corners of 4X4 m squares between stands 20 and 21, and 60 and 61. 68 bank voles were caught. Oats were found in the stomachs of 56 voles caught at sites located at all possible distances from exposition sites. The percentage of oats in the stomachs was negatively correlated with the distance between the point of catching and the oat exposition áite. The individuals that had no oat in stomachs were all caught at stands more than 200 m from the exposition sites. Similar relationships were established for reproducing females. It was assumed that: (1) the 300 m range of penetration around oat supply sites is either a long axis of an elliptic range or a radius of a circular one, (2) the fact that around 30 individuals could visit each exposition site meant that at least 30 home ranges overlapped there. With these assumptions applied, the estimated area of a home range was 3.5 (elliptic), or 7.0 hectares (circular), and corresponding population densities were 4.25 to 8.50 individual per hectare. The size of zone affected by the trap line has been estimated to cover 72 hectares and the effectiveness of removal at any trap site to be at 12 to 24 per cent. The need to review all the population parameters determined on plots of a several hectare size "saturated" with traps is therefore stressed.

. 1993. The influence of landscape spatial structure on small mammal movements. Acta theriol. 38: 113 -123.The present knowledge of the range of small mammal (field mice Apodemus agrarius (Pallas, 1771) and bank vole Clethrionomys glareolus (Schreber, 1780)) movements is discussed and data concerning long distance movements obtained by the authors are presented. Small mammals appeared to be much more mobile than it is commonly believed. Spatial distribution of movements is not random and some routes of movements can be recognized. Such routes are covered mainly by ruderal vegetation and dense bushes. Considerable mobility of small mammals found in the presented studies encourages to think over the present views on organization and regulation of populations.

-Werka J. 1990. Use of agricultural habitats by roe deer inhabiting a small forest area. Acta theriol. 35: 121 -127.Faeces distribution analyses and direct observation of animals were employed to determine the range of use of agrocoenoses by the roe deer Capreolus capreolus (Linnaeus, 1758), inhabiting a small forest (about 200 ha) surrounded by fields. The highest roe deer pellet density and 2/3 of the roe deer sighted were found in the zone 100-200 m from the forest tree-stand edge. The zone of roe deer penetration around the forest, calculated from pellet density decrease regression lines and decreasing numbers of grazing roe deer with a growing distance from the forest, was about 500 m wide.