The terrestrial habitat use of the common spadefoot was studied in an agricultural area and an old riverdune landscape. In an agricultural area potatofi  elds were the most important terrestrial habitat, in the old sanddune landscape half open sanddunes, sandy pathes between a deciduous wood and a pinewood and sandy pathes in a deciduous wood.

The genome size variation in almost four hundred specimens of Pelobates fuscus fuscus, collected from 61 localities in Russia, Latvia, Belarus, Ukraine, Moldavia, and Kazakhstan, was studied by DNA flow cytometry. The existence of two geographic groups differed by genome size was confirmed by allozyme analysis. The distribution of the western type (with smaller genome size) and the eastern type (with larger genome size) P. f. fuscus is described.