Tracing size distribution patterns in two Martes species across Eurasia: which populations should be protected?

Abstract

My aim is to identify the general and specific patterns in the geographical distribution of sable, Martes zibellina, and pine marten, Martes martes, sizes, as well as one sibling species in the general range. For each species, a comparative analysis of the response to environmental gradients in different areas of their ranges was carried out. For the range of each species, as for the twin species, the global trend presented an increase in size from the Pacific to the Atlantic, which revealed a negative longitudinal trend that was more pronounced in the marten. The sable follows Bergmann’s rule, whereas the marten demonstrates a significant reverse trend. As a species, the marten shows a significant clinal growth that is directly correlated to the increase in the average annual temperatures and January temperatures, as well as with increased elevation (without any reaction to the July temperatures). As a species, the sable does not correlate with the temperature or elevation gradients. New and diverse patterns of sable and marten sizes across Eurasia were identified. The two species demonstrate the existence of a single zone of minimum sizes in the entire range, and there is a new feature of the growth to the east of the zone where the dimensions are minimal. The marten is adapted to a temperate climate, whereas the sable is adapted to cold and extreme climates. I have proposed several corrections to the conservation plans based on knowledge of the biological characteristics of the marten and sable populations and subspecies.