The seasonal changes of the soil and water temperature of reservoirs the forest (the Klyazma river) and meadow (the Oka river) floodplains inhabited by the Russian desman were studied. The temperature range which the animal lives within varies from 0 - 7°C in the winter to 8 - 23°C in the summer. Due to the large volume of water and groundwater, desmans do not face negative temperatures in the winter in their burrows.