Findings of overground nests of rodents in the Ukrainian Beskids (upper course of the Dnister)

Materials are collected and generalised on the overground nesting activity of 4 rodent species under conditions of the north Carpathian taiga: the red squirrel (Sciurus vulgaris), the edible dormouse (Glis glis), the hazel dormouse (Muscardinus avellanarius), and the harvest mouse (Micromys minutus). The locality is characterised by a combination various habitats. Common and unique variants of nests of these species are described, particularly the arrangement by the hazel dormouse of its own nests in nests of the Eurasian wren and song thrush, an unusual nest of the red squirrel, and the nesting of the edible dormouse in an abandoned dress.

Assessing the occupation of nest boxes by dormice (Gliridae) in the Carpathian forests

Nest boxes for dormice (Gliridae) can significantly increase the habitat’s carrying capacity for these species in areas under high anthropopressure and facilitate the long-term monitoring of populations. As part of the active protection of dormice in the Carpathian Landscape Parks in Małopolska, in August and September 2019, 575 boxes of two different sizes were checked for the presence of adults, young or nests. Additionally, habitat conditions within a 25 m radius were recorded (e.g. forest stand, estimated understory cover, the approximate number of natural shelters, fruiting plant species). The vast majority of all nest boxes – 79% – were used by dormice, but also birds and insects frequently occupied these shelters. Out of four species of dormice that occur in Poland, two were recorded in the study area: hazel dormice Muscardinus avellanarius and fat dormice Gli sglis. They were found in all surveyed landscape parks and inhabited mainly fir stands. Hazel dormice preferred smaller nest boxes and were generally more common than fat dormice, which preferred large boxes. On the other hand, fat dormice were more common in areas rich in fruiting plant species. Our research thus confirmed the usefulness of artificial shelters for dormouse in active protection.

They don’t live forever: How life history data and encounter probability help to assess success of Muscardinus avellanarius translocations (Rodentia: Gliridae)

The hazel dormouse (Muscardinus avellanarius) is a European Protected Species and for this reason, hazel dormice are protected from deliberate killing, injury or disturbance and its sites and resting places are also protected. During development projects impacts on hazel dormouse individuals and populations should be avoided. If avoidance is not possible measures of mitigation and compensation have to be implemented. In many cases the only suitable measure to prevent disturbance, killing or injury of individuals is the translocation of hazel dormice to another suitable habitat. The success of translocations has so far been rarely documented. To assess the success of translocations, the natural mortality of hazel dormice has to be considered as well as the likelihood of finding specific individuals during the proposed action. How these data affect the assessment of translocation success is calculated based on published data on seasonal survival rates of different cohorts and of unpublished monthly encounter probabilities of a population of marked animals. Depending on the time between the translocation event and the subsequent monitoring controls the number of hazel dormice likely to be alive can be low. For this reason, success cannot be evaluated with our method if the sample size is too small.

What Muscardinus avellanarius like but consultants don’t: performance of nest boxes vs. nest tubes for translocations (Rodentia: Gliridae)

Nest boxes and nest tubes are widely used for surveys, for both research and development purposes, to detect and survey hazel dormice (Muscardinus avellanarius). In order to compare the performance of the two devices for translocations a study was conducted where hazel dormice had the choice between nest boxes and nest tubes. Hazel dormice preferred nest tubes over nest boxes but escaped more often from nest tubes than from nest boxes during checking. We conclude that nest boxes are the better choice for translocations as they offer the better escape ratio over nest tubes.

Prevalence and seasonal variation in ticks on Muscardinus avellanarius from Germany (Rodentia: Gliridae)

We sampled ticks infesting hazel dormice (Muscardinus avellanarius) between May 2017 and September 2017 at seven locations in Germany. Of a total of 221 dormice examined, 19% were infested by ticks, but the prevalence of infestation varied strongly between sites and months. The highest prevalence at one site was noted in September (55%) while the lowest was in July (0%). In June, prevalence differed between sites from 0% to 47%. Most frequently, dormice were infested by one tick. The maximum number of ticks found on one animal was 12. All ticks were detected on the head of the animals, where the most common feeding sites were ears, nose and the area around the eyes.