Mustela eversmanii Linnaeus 1758

42.

Steppe Polecat

Mustela eversmanii

French: Putois d'Eversmann / German: Steppeniltis / Spanish: Turon estepario

Taxonomy. Mustela eversmanii Lesson, 1827,

Russia.

The Steppe Polecat was considered conspecific with either M. putorius or M. nigripes by some authors. Up to nineteen subspecies have been proposed, but a taxonomic revision is needed.

Distribution. SE Europe, Caucasus, and Middle East through C Asia to NE China, Mongolia, and Russian Far East

Descriptive notes. Head-body 37-56.2 cm (males), 29-52 cm (females); tail 8-18.3 cm (males), 7-18 cm (females); weight 2:05 kg (males), 1-35 kg (females), adult males are larger than females. The Steppe Polecat closely resembles the European Polecat. The pelage is highly variable in color, but generally is yellowish-white to brown, with the upperparts darker than the undersides. The fur on the chest, limbs, and tail is darker in color, and there is a dark mask on the whitish face.

Habitat. Steppe, open grasslands, and semi-desert.

Food and Feeding. The diet includes rodents (voles, hamsters, marmots), other small mammals (pikas, ground squirrels), birds, eggs, reptiles, and insects. In Hungary, the principle food consists of small mammals; their frequency fluctuates between 54% and 93%, reaching a maximum in summer. In all seasons, the most important prey is the Common Vole (Microtus arvalis) and the Common Hamster (Cricetus cricetus); in addition, the European Souslik (Spermophilus citellus) is occasionally consumed in spring and autumn, and Brown Rats (Rattus norvegicus) may be eaten in autumn. The European Hare is eaten only in winter (5%). The consumption of birds (mainly Passerines) is considerable in spring (38%) and autumn (29%). A stable isotope study revealed a diet that comprised 27% small mammals (Plateau Pika, Root Vole, and Plateau Zokor) and 47-7% adult passerine birds, with hatchlings contributing 25:6%. Steppe Polecats hunt by exploring the burrows of their mammalian prey and thus they may spend much time underground.

Activity patterns. Primarily nocturnal. Den /rest sites are in burrows expropriated from other animals.

Movements, Home range and Social organization. Steppe Polecats are solitary. They move rapidly, constantly exploring new ground and searching for food, and may cover up to 18 km during the night. Local migrations may occur to areas with greater food abundance or less snow.

Breeding. Mating occurs from February to March, with births from April to May. Gestation lasts 38-41 days. Litters are large, usually from eight to ten. The young weigh 4-6 g at birth, open their eyes after one month, and are weaned and start hunting with the mother at 1-5 months. They disperse at three months. Sexual maturity is reached during the first breeding season, when the young are nine months old.

Status and Conservation. Classified as Least Concern in The IUCN Red List; the subspecies M. e. amurensis, of south-eastern Siberia and Manchuria, is classified as Vulnerable. Little is known about this species and field studies are needed to learn more aboutits natural history, ecology, and conservation status. It is not intentionally hunted except in Russia, but is heavily impacted by persecution in the western parts of its range.

Bibliography. Lanszki & Heltai (2007), Stroganov (1969), Wozencraft (2005, 2008).