157.

Tatra Pine Vole

Microtus tatricus

French: Campagnol des Tatras / German: Tatra-Kleinwihlmaus / Spanish: Topillo de los Tatras

Other common names: Tatra ole

Taxonomy. Pitymys tatricus Kratochvil, 1952, Vel’ka Studena Valley, High Tatra Mountains, Slovakia.

Microtus tatricus is in subgenus Terricola and possibly a close relative to multiplex species group. It was classified in the genus Pitymys . Two subspecies recognized.

Subspecies and Distribution.

M.t.tatricusKratochvil,1952—TatraM.t.(WCarpathians)inSPolandandNSlovakia.

M. t. zykovi Zagorodnyuk, 1989 — E & S Carpathian M.t. in SW Ukraine and Romania.

Descriptive notes. Head-body 83-115 mm, tail 31-47 mm; weight 18-36 g. Males are slightly larger (mean weight 30-2 g) than females (25-1 g). The Tatra Pine Vole is moderately large, with relatively long tail of 35-41% of head-body length. Ears are moderately large, but eyes are tiny, measuring at most 2:5 mm in diameter. It is unique among pine voles in having six plantar pads. Females have two inguinal pairs of nipples. Fur is coarse, giving appearance of the Short-tailed Field Vole ( M. agrestis). Back of the Tatra Pine Vole is dark brown, and belly is silver or gray, lightly shaded buff. Tail is bicolored, and terminal pencil is prominent. Feet are whitish. Skull is large and rather deep, with obvious supratemporal ridges. Molar pattern does not deviate from that seen in Liechtenstein’s Pine Vole ( M. liechtensteini).

Habitat. Montane spruce ( Picea) dwarf pine ( Pinus mugo) forests, both Pinaceae, and alpine meadows at elevations of 600-2340 m, most often 1100-1700 m. The Tatra Pine Vole prefers talus slopes and meadows with light and humid soil and dense vegetation. Characteristic habitat is spruce forest with dense fern undergrowth and numerous fallen logs. It is absent from deciduous forests.

Food and Feeding. In summer, the Tatra Pine Vole feeds primarily on green leaves, followed by stems and roots; insects are an insignificant part of diets. Dicotyledonous plants dominate over grasses, mosses, and berries. The most common plants in diet, in decreasing order of importance, are wood sorrel ( Oxalis acetosella, Oxalidaceae), purple coltsfoot ( Homogyne alpina, Asteraceae), grasses, hairy chervil ( Chaerophyllum hirsutum, Apiaceae), common chickweed ( Stellaria nemorum, Caryophyllaceae), Austrian leopard’s bane ( Doronicum austriacum, Asteraceae), willow gentian ( Gentiana asclepiadea, Gentianaceae), mountain sow-thistle ( Cicerbita alpina, Asteraceae), and purple avens ( Geum rivale, Rosaceae).

Breeding. Breeding season of the Tatra Pine Vole lasts ¢.140 days. It starts in April, occasionally under snow, peaks in June, and terminates in September. Numbers of embryos are 1-4/female (mean 2-5). Average female has 7-9 young/season. Litters can be sired by different males. Young of both sexes attain sexual maturity in their second year. Average longevity is 367 days, and maximum life expectancy is 15-18 months. Tatra Pine Voles can survive two winters.

Activity patterns. Tatra Pine Voles are nocturnal in summer. They are semi-fossorial and excavate extensive burrow systems but mainly feed aboveground. They are active year-round and move under snow in winter.

Movements, Home range and Social organization. In Slovakia, male Tatra Pine Voles had significantly larger home ranges (835-6 m®) than females (585-6 m?) and were more mobile. Males traveled further (22-3 m in males vs. 14-6 m in females) and were trapped at longer distances (36-7 m vs. 21-5 m) than females. Longest recorded movement was more than 260 m.

Status and Conservation. Classified as Least Concern on The IUCN Red List. The Tatra Pine Vole has small distribution, narrow habitat requirements, and small populations. The western isolated population supposedly occupies ¢.840 km* and has 200,000— 250,000 individuals.

Bibliography. Balaz & Ambros (2012), Jur€ovitova & Rudéa (2006), Kristofik & Danko (2012), Martinkova & Dudich (2003), Niethammer (1982i), Ruda et al. (2010), Shenbrot & Krasnov (2005).