Ochrona przyrody a inwazja norki amerykańskiej (Neovison vison) w Polsce - krytyczna analiza problemu

The American mink (Neovison vison) is a species that experienced unprecedented ecological success in the 20 th century, which can be seen in both the dynamic increase in its zoogeographical range, and in its effective adaptation to ecological niches in new areas. The driving forces of this phenomenon include intensification and globalization of mink farming, which is accompanied by introduction and rapid spread of the species outside its natural range. The first observations of mink in the wild in Poland took place in the middle of the last century. Within 60 years, American mink colonized almost entire country and the process of invasion and colonization is still ongoing. The high rate of invasion and ecological success achieved by the populations from the introduction is possible due to the high ecological plasticity of American mink, its high reproductive potential, the availability of free ecological niche left by European mink (Mustela lutreola), extinct in many areas, and the frequent lack of natural enemies on the occupied territories. Dynamic geographical spread of allochthonous American mink is associated with a number of very serious ecological problems, primarily through predation, competition and aggression against indigenous fauna, as well as transmission of Aleutian mink disease virus. This results in fact that American mink is regarded as one of most dangerous invasive species in the world. In the absence of practical possibilities of its permanent eradication from Poland, local eradication programs on vulnerable areas (e.g. waterbirds breeding sites), as well as large−scale population size control, promotion of natural enemies and competitors, and improvement of living conditions of its prey−species are most recommended. The most important in monitoring and control programs of alien populations is limitation of farm−animals escapes and recognition of methods for their simple and unambiguous identification. Indisputable determination of the free−ranging animals origin would allow for taking the appropriate actions against owners of the unsafe farms. At the same time, implementation of a holistic and systemic approach to solve the problem of the presence of American mink in the natural environment would help to fulfil Polish obligations resulting from ratified international conventions and EU law.