Ecological characteristics of the Siberian salamander (Salamandrella keyserlingii, Caudata, Hynobiidae) from the coastal part of the Sea of Okhotsk

Abstract

The integral influence of harsh climatic conditions on the main ecological characteristics (seasonal and diurnal activities, dynamics of the sex–age structure, fecundity of females and its variation in different waterbodies, etc.) of the Siberian salamander (Salamandrella keyserlingii Dybowski 1870) was studied in populations from two types of waterbodies in the northeastern outskirts of the range near the city of Magadan. The majority of the studied characteristics appeared to be similar to those in other populations, including the most southern ones. Regardless of the harsh climatic conditions and the short period of activity (4–4.5 months vs. 6–6.5 months in the southern part of the range), the abundance of the salamanders in the northern Sea of Okhotsk is extremely high and the spectrum of inhabited biotopes is wide. A numerous group of animals (up to a quarter of specimens captured in the first half of summer) was found that had reached the age of sexual maturity (subadultus). This group was not identified in populations from other regions, most likely owing to the small number of samples and their incomplete analysis. In general, the state of the population makes it possible to characterize the studied outskirt part of the range as located in one of the areas of the ecological optimum. Only the data on the size of animals contradict the suggestion stated above because due to the high portion of small adult specimens the average body length of adult salamanders is lower in the vicinity of Magadan compared to many other regions.