European ground squirrel  (Spermophilus citellus)

Classified as Vulnerable (VU) on the IUCN Red List (1).

The European ground squirrel belongs to a genus commonly referred to as the sousliks, with representatives spread throughout the northern hemisphere from California to China (3). Ground squirrels tend to have stout, low-slung bodies, resting upon short legs, and a well-furred tail measuring about a third the length of the body (2) (3) (4). The European ground squirrel generally has short yellowish fur but the back is tinged distinctly grey with dense cream spots (2) (3). All species within the genus have sizeable internal cheek pouches for carrying food (3).

The European ground squirrel is endemic to central and eastern Europe, from the Czech Republic in the northwest to Turkey in the southeast (1). Historically, its western boundary extended into southeast Germany (1) (2).

An inhabitant of open landscape without dense vegetation cover, the European ground squirrel is normally found in short-grass habitats on light, well-drained soils (1) (3). This includes a range of natural and artificial habitats such as steppe grassland, pasture, vineyards, sports fields and golf courses (1).

Although the European ground squirrel lives in burrows in loosely structured populations, it is not an exceptionally social or territorial species (2). In common with all ground-dwelling squirrels, it is mostly active during the hours of sunlight, devoting most of its attention to foraging for food. Roots, seeds, shoots and flowers comprise the bulk of this species’ diet, but occasionally small invertebrates will also be taken (1) (4). However, as an important part of the food chain itself, it is commonly preyed upon by larger predators such as polecats and birds of prey (5) (6). During the summer months, there is a rise in foraging activity as each ground squirrel attempts to accumulate as much stored fat as possible before the onset of hibernation (2). Unlike many other ground squirrels, it does not stock-pile food but must rely on doubling its body mass to see it through the long winter (2) (3). Entering hibernation near the beginning of September, European ground squirrels do not appear from the underground burrows again until late March. Soon after emerging there is a scramble amongst the males to gain access to the reproductively active females. This period of breeding lasts three to four weeks, with each female mating with only one male. Following 25 days of development in the womb, the females give birth to a litter of 4 to 11 young which receive milk for around 30 days before being weaned. The young reach maturity after the following hibernation, but not all will breed in their first year (3).

The conversion of steppe grassland and pasture into cultivated farmland and forestry is chiefly responsible for a serious decline in the population of European ground squirrels (1) (3). As a consequence of the rapid loss of suitable habitat, the population is becoming severely fragmented, whilst its range is retracting, particularly in the west (1). Furthermore, as an integral part of the food chain, a decrease in the number of European ground squirrels is probably responsible for a decline in the populations of many other vulnerable species (5).

The European ground squirrel is listed on Appendix II of the Bern Convention and Annexes II and IV of the EU Habitats and Species Directive (1). Under this legislation, it is the responsibility of the countries within the species’ range to ensure its conservation (7). In 2005, this species was reintroduced successfully to Poland and a project has recently been initiated to reintroduce it into Germany. One of the main priorities of conservation efforts is to conduct further studies into the ecology, threats and population biology of the European ground squirrel. This research will provide crucial data in determining appropriate future conservation measures (1).

View information on this species at the UNEP World Conservation Monitoring Centre.

For more information on the conservation of European ground squirrels see:

• The Rufford Small Grants Foundation:
  http://www.ruffordsmallgrants.org/rsg/Projects/YordanSpasovKoshev