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1

Home ranges of European mink Mustela lutreola in Southwestern Europe

100%

Garin I. , Zuberogoitia I. , Zabala J. , Aihartza J. , Clevenger A. P. , Rallo A.

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nr 1

EN

We radiotracked 7 European mink Mustela lutreola Linnaeus, 1761 (5 males and 2 females), to determine their distribution, size and temporal changes of their home range in an area of southwestern Europe, where American mink M. vison was not established. Size of home ranges varied from 11 to 17 km along watercourses in males and were 0.6 and 3.6 km in females. Home ranges of males were larger than those found in previous studies. Most females captured (either radiotracked or not) were found within the home range of males. Males occupied adjoining river sections with minimal range overlap, suggesting an intrasexually exclusive spacing pattern for males. Each month males used new river stretches, mainly along tributaries; meanwhile they showed a steady use of their stem river section. Resting sites were mainly beneath dense brambles of Rubus patches located in the river bank.

2

Spatial behaviour of European mink Mustela lutreola and polecat Mustela putorius in southwestern France

84%

Fournier P. , Maizeret C. , Fournier-Chambrillon C. , Ilbert N. , Aulagnier S. , Spitz F.

Acta Theriologica

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2008

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tom 53

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nr 4

EN

The European minkMustela lutreola Linnaeus, 1761 and the European polecatMustela putorius Linnaeus, 1758 are sympatric in southwestern France. They are related species but the former is highly threatened whereas the latter maintains good populations. Nine European mink and 14 polecats were radiotracked in the Landes de Gascogne region to compare their space use and to identify appropriate conservation measures for the European mink. Resting animals were located once a day and active animals were tracked by continuous monitoring. European mink had linear home ranges whose sizes were larger than predicted by Johnson’s model (mean±SD=2971±1888 ha in males and 257±113 ha in females). They travelled long inter-day distances (1.4±1.9 km in males and 0.4±0.6 km in females). Polecats had home ranges of various shapes (linear, circular or combined) and their sizes were consistent with Johnson’s model (707±779 ha in males and 51±58 ha in females). They also had shorter inter-day distances than mink (0.7±0.9 km in males and 0.2±0.4 km in females). However male polecats had longer activity bouts than male mink. Thus European mink exhibit large movements between small and distant activity areas while polecats compensate for their smaller range by a higher activity in restricted areas. The behaviour of the European mink appears to be an adaptation to habitats scattered over linear ranges. This extensive use of space suggests that conservation of this endangered species cannot be achieved in the confinement of Europe’s natural reserves. Conservation plans should aim at maintaining high quality habitats along entire river networks and ensuring safe movements for the animals, preventing particularly the risk of collisions with vehicles.

3

Habitat utilization by sympatric European mink Mustela lutreola and polecats Mustela putorius in South-Western France

84%

Fournier P. , Maizeret C. , Jimenez D. , Chusseau J.-P. , Aulagnier S. , Spitz F.

Acta Theriologica

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2007

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tom 52

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nr 1

EN

The European minkMustela lutreola Linnaeus, 1761 and the European polecatMustela putorius Linnaeus, 1758 are related species sympatric in southwestern France. The European mink is rapidly disappearing whereas the polecat maintains good populations. Seasonal habitat use of both species was compared in the Landes de Gascogne region to identify if some vulnerability factors of the European mink were associated with habitats occupied by this mustelid. Potential habitats were mapped using a satellite picture and 12 main types of habitats were defined. Animal locations were recorded by radiotracking 9 European mink and 14 polecats from March 1996 to August 1999. Resting animals were located by triangulation, and, when possible, resting places were described. Animals in activity were tracked by continuous monitoring. Data collected revealed a strong preference of European mink for flooded habitats, particularly open marshes, flooded woodlands and moorlands. They seldom left the corridor of the riparian forest and their resting places were mainly in flooded environments, above ground (under herbs or bushes) or in cavities between tree roots. European polecats were less tightly linked to wetlands. Most of their locations were in the pine forests outside the valleys and their resting places were mainly in burrows. The strong specialisation of European mink in aquatic habitats is probably one of the main reasons for its decline because wetlands suffer drastic damages throughout all of its range. Maintaining adequate water levels is crucial for satisfying habitat requirements of mink.

4

Reproductive plasticidy of the American mink Mustela vison in Belarus

84%

Sidorovich V. E.

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nr 2

EN

Reproduction of the American mink Mustela vison Schreber, 1777 population introduced to Belarus was studied in 1983 — 1992. Material consisted of 52 male genitalia, carcasses of 45 pregnant females, and observations of 19 litters with blind cubs and 31 litters with larger cubs, The study was conducted in two areas in northern Belarus: Rossony, where the decrease of mink numbers due to excessive trapping was recorded, and Gorodok, where the expansion of American mink in the presence of the native European mink Mustela lutreola was observed. Mating period of American mink lasted from mid February to mid April. Young were born from April till mid June. Litter size was on average 4.2 (blind cubs) and 3.3 in older cubs (> 2 months old). Reproduction intensity on Drissa river and its tributaries was related to density. On average, 3.3 embryos per pregnanat female were found in 1-yr females and 4.3 in > 2-yr old females at the density of 13.3 mink/10 km of watercourse. In the low density population (2.8 mink/10 km due to overexploitation by hunters) reproduction intensity increased to an average of 4.2 embryos in 1-yr females and 6.0 in £ 2-yr females. During population decrease, percentage of young increased and the sex ratio became biased towards females. In an expanding population of American mink that had newly colonised Lovat river, the reproduction was very intense (7.3 - 7.6 embryos/female). The results show a great reproductive plasticity of American mink that obviously helped this species to successfully colonise new ranges after introduction.

5

Sexual dimorphism in the skull of the European mink Mustela lutreola from NW part of Russia

84%

Abramov A. V. , Tumanov I. L.

Acta Theriologica

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2003

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tom 48

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nr 2

EN

Morphometric variation in 22 characters of 86 skulls of the European mink Mustela lutreola (Linnaeus, 1761), from the NW part of Russia, has been analysed. Stepwise discriminant analysis was used to estimate craniometric variables for sex determinations. Two characters (zygomatic breadth and interorbital width) are enough for the 96.5% correct classification. The male skull of M. lutreola is characterised by a relatively high neurocranium, widely arranged zygomatic arches, a wide rostrum, and by wider auditory bullae and higher mandibles. Sexual size dimorphism of M. lutreola is less than that of other similar-sized mustelids - Mustela putorius, M. eversmanii, M. sibirica, Neovison vison. The results are discussed in relation to the existing theories on sexual dimorphism in mustelids.