Earth dogs (“Laluger” in Bulgarian) are a species of small rodent in the squirrel family. Unlike their related squirrels, earth dogs lead a terrestrial lifestyle. The length of the body, including the head, is 164–205 mm, and the tail measures 40–74 mm. Their color ranges from yellowish-brown to yellow, sometimes with dark spots on the back.
The ground squirrel is distributed throughout the eastern parts of the Balkan Peninsula and the Middle Danube Lowland, as well as in Wallachia, Moldova, Bukovina, and the Czech Republic. It is considered extinct in Germany, Croatia, and Poland, where attempts are being made to reintroduce the species. In Bulgaria, it is found throughout the country, mainly in the plains. Earth dogs prefer open areas with low grass vegetation, often near arable land.
The Laluger is active mainly during the day. Between October and March, and for a longer period in the mountains, it hibernates. It inhabits underground tunnels ranging from 150 to 315 cm in length, with the living chamber located at a depth of 40 to 170 cm. In autumn, it digs a vertical tunnel above the living chamber that does not fully reach the surface and fills the summer entrance to the dwelling with the excavated soil. After the end of hibernation, it completes the digging of the vertical tunnel, through which it emerges to the surface.
