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Nest site preference of forest dormouse Dryomys nitedula (Pallas) in the north-western corner of the distribution range

Juškaitis R., Balčiauskas L., Šiožinytė V.

Polish Journal of Ecology

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2012

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Vol. 60, nr 4

815--826

EN

Lithuania is situated in the very north-western corner of the large distribution range of the forest dormouse Dryomys nitedula and it might be considered that dormouse habitats should be both different and sub-optimal in this area in comparison to central parts of the range. The aims of the present study were to analyse which vegetation parameters determine nest site preference of D. nitedula and to compare these with nest site preferences of other dormouse species. The population of D. nitedula was studied from 2001 to 2011 using nestboxes set up in a grid system, with regular control of the nestboxes and ringing of dormice captured. During entire study period, 97 individuals were marked with rings and the total number of dormouse captures was 440. Vegetation parameters (the composition of the overstorey and understorey, the numbers and cover of different tree and shrub species, absence of vegetation etc.) were evaluated quantitatively in areas of 2500 m2 around 58 nestboxes at this study site. During the period 2001–2002, the abundance of D. nitedula was relatively high, with the dormice using the entire area of the study site, showing a preference for nest sites with a more diverse overstorey and understorey. However, no significant correlations were found between indices of nestbox use and other vegetation parameters in this period. During the period 2003–2011, when the dormouse abundance was lower but stable, dormice used only part of the study site area, in this preferring nest sites with a better developed and diverse understorey (especially with young rowan, lime and aspen trees), with more abundant mature oak, lime and black alder trees and a higher percentage of raspberry and bramble cover, as well as overgrown clearings. D. nitedula avoided nest sites with higher total number of mature trees (especially Scotch pine and Norway spruce), as well as areas with higher percentage of bilberry cover and open areas (rides, presence of stumps). In general, a well-developed and diverse understorey was the main habitat component which determined nest site preference of D. nitedula in the very northwestern corner of its range. Thus, D. nitedula retains its main habitat requirement which is characteristic also for other parts of its large range. Vegetation parameters determining nest site preference of D. nitedula are rather similar to nest site preference of the common dormouse Muscardinus avellanarius. However, D. nitedula may live in less rich habitats probably because their diet includes more food of animal origin.

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The importance of animal food for Dryomys nitedula (Pallas) and Glis glis (L.) In Białowieża Forest(East Poland): analysis of faeces

Nowakowski Wojciech K., Godlewska Monika

Polish Journal of Ecology

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2006

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Vol. 54, nr 3

359-367

EN

Fresh faeces of dormice found in nestboxes along the permanent transect in Białowieża Forest were analysed. The study area was a managed forest of diverse biotopes. In total, 196 samples of faeces of the forest dormouse (Dryomys nitedula) and 62 of edible dormouse (Glis glis) were examined. In the faeces analysed, the following categories of food remains were distinguished: chitin carapaces, calcareous shells, feathers, seeds, plant fibres. In the forest dormouse, chitin carapaces were found in 100% of samples, but in only 8% of the edible dormouse samples. Feathers were noted in 36% of samples of forest dormouse faeces, but only in 12% of samples from the edible dormouse. Calcareous shells were found in 14% of forest dormouse samples and 1.6% of edible dormouse faeces. Remains of animal food were found in 100% of samples of forest dormouse excrements, but only in 29% of samples from the edible dormouse. The highest percent of faecal samples with animal remains was found in the edible dormouse in July, while in the forest dormouse seasonal variation occurred only in some types of animal remains. Most of the chitin carapaces identified in forest dormouse faeces came from Chilopoda (45%), Hemiptera (33%) and Coleoptera (22%). In faeces of the edible dormouse the majority were remains of butterflies (55%). The results presented here suggest an almost total separation of the food niches of the two dormouse species.

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Home ranges, nest sites and population dynamics ofthe forest dormouse Dryomys nitedula (Pallas)in an oak-hornbeam forest: a live-trappingand radio-tracking study

Ściński Michał, Borowski Zbigniew

Polish Journal of Ecology

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2006

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Vol. 54, nr 3

391-396

EN

Population dynamics, space use and interspecific interactions of the forest dormouse Dryomys nitedula were studied for four years in an oak-hornbeam forest in the Białowieża Primeval Forest (NE Poland). Animals were captured with live-traps and marked by ear-tattooing. Population density ranged from 1.4 to 18.6 individuals x 10 ha^-1. Dormice reproduced in all years of study (2001-2004). Offspring were born in June and first juveniles were caught at the beginning of August. The last dormice were captured at the end of September. Three forest dormice (1 male and 2 females) were radio-tracked during first half of June 2001. Male home range area was larger (4.2 ha) than home range areas of females (0.75 and 0.73 ha). The longest distance between two consecutive daytime nest sites was 275 m for the male and 126 m for the females. Average home range length calculated from radio-tracked individuals (218 m) was larger than the one from live-trapped dormice (93 m). Dormice used bird nest boxes and tree hollows for daytime nest sites. They preferred nesting in the nest boxes previously occupied by birds and they used old bird nest material for the nest construction. Home ranges of radio-tracked forest dormice overlapped widely with home ranges of fat dormice Glis glis. Most of live-traps used by the forest dormouse were also visited by the fat dormouse.

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Food preferences of Glis glis (L.), Dryomys nitedula (Pallas) and Graphiurus murinus (Smuts) kept in captivity

Nowakowski Wojciech K., Remisiewicz Magdalena, Kosowska Joanna

Polish Journal of Ecology

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2006

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Vol. 54, nr 3

369-378

EN

We investigated food preferences of three species of dormice, testing consumption by captive animals. One type of food was provided to an animal and its "suitability" scored for each species, according to whether it was or was not consumed. If it was eaten, the time when it was consumed was recorded (after 24, 48 or 72 hours). In total, 17 types of animal food and 46 of plant food were tested. Animal foods offered included different arthropods, eggs, snails and chicken meat. Plant food consisted of fruits, seeds, nuts and green parts. Glis glis consumed -24% of animal material offered and 100% of plant food types, Dryomys nitedula consumed - 77% of animal and 54% of plant food types. Graphiurus murinus consumed - 94% of animal and 63% of plant food types. G. glis showed a significantly higher preference for plant foods rather than animal material, and preferred plant food much more than the other two species. Both D. nitedula and G. murinus preferred animal more than plant food and and did not differ in preferences and diversity of both kinds of food they consumed. Thus, G. glis can be considered as principally a herbivore, while D. nitedula and G. murinus are rather meat-eaters. It can be concluded that food niches, especially of the two European dormice, are separate and thus in natural conditions they do not compete strongly for food resources.