Asiatic Toad: “Le secret de Polichinelle” (Open Secret) in Amur Region

The life of amphibians in Northern Eurasia is possible only because of their specific adaptations to extreme temperatures on land or to hypoxia in water. This aspect of amphibian ecology is still little studied; even the wintering places of many amphibians are not well-known. A good example of such a situation in the Amur region is the Asiatic toad. Finds of animals wintering on land and in water in late autumn are rare. It is unclear whether the toads survive until spring. Like other toad species in Northern Eurasia, this one does not tolerate cooling below –3°C. However, such temperatures are typical at a depth up to 1.5 m in the soils of flat areas from Komsomolsk-on-Amur to Blagoveshchensk. It turned out that the place of mass wintering of toads is the Open Secret (Le secret de Polichinelle): toads regularly enter the nets of fishermen under the ice on the Amur (between Khabarovsk and Komsomolsk-on-Amur) along with fish. Observations have shown that in spring, adults and subadults, females and males come out from the water simultaneously before the ice drift or immediately after it. In autumn, the toads do not go to wintering at the same time, so this is not so evident. Probably, in the north, in the Russian part of their range, the main place of their wintering is in the plains of rivers, while in the south (in Central and Southwestern China), mainly in the upper soil horizons.

, Asiatic toad, , wintering