Topographic distribution and daily activity of the European ground squirrel population in Bugacpuszta, Hungary

Abstract

Factors affecting the population density and daily pattern of activity of the European ground squirrelSpermophilus citellus (Linnaeus, 1766) were studied in two habitats of the Kiskunsag National Park, Hungary. One habitat was dominated by sandy and the other by salty grassland. Population densities were estimated by counting ground squirrel burrow entrances in sample areas with different microhabitat characteristics. Three categories (elevated, level and depressed) were used to describe the spatial distribution of burrows according to microtopography. Daily activity was evaluated by counting the ground squirrels visible on the surface and registering their alarm calls. The highest proportion of ground squirrel holes was found on elevations in the two habitats. Ground squirrels showed a similar daily activity pattern in different areas and in the same season in consecutive years. The daily activity consisted in a morning peak, a midday pause and a less regular afternoon activity period. Human activity had no direct effect on the daily activity pattern. Emission of alarm calls peaked in June, when litters emerge from the maternal burrows.