Discrimination between the domesticated and the feral American mink in Poland based on the left track of a forelimb

Abstract

In Poland, American mink lives in a natural environment as a non-indigenous species which occupied the ecological niche left by European mink (Mustela lutreola). The first signals of American minks appearing in the wild date back to 1962–1963. According to some authors in the 1980’s there were introductions of minks from fur-farms what resulted in modifications of genetic structures in the population of wild minks. They also claim that up to this day it is not known how the process of local population’s augmentation ran or in what ways farm minks influenced the population of the wild ones. The aim of study was defining the differences between feral and currently bred in farms American minks. They were based on the track of a forelimb left by both types of minks. The study included minks caught in their natural habitat and taken from fur-farm. Both places where the biological material was obtained were in the same area, i.e. Western Pomerania in Poland. Modelling clay was used to show differences in track’s size between the feral and the farm mink. Artificial imprints of left front mink’s paw was made in it and photographed. As a result of studies found that basing on the metacarpal pad imprint left by a mink, it is possible to assess its origin. The feature for the farm minks ranged between 128.28–167.98 mm2 and for the feral minks 75.99–106.1 mm2. Therefore, it can be assumed that finding an imprint of a surface above 120 mm2 can be a foundation to establish the track’s origin as the farm mink’s. A good indicator to establish a track’s origin, if it is wild or farm mink’s, is analyzing the proportions between the track’s height and the height or the width of the second digital pad.