A review of the status of the Western polecatMustela putorius: a neglected and declining species?

Abstract

The Western polecat Mustela putorius has a widespread European distribution and is currently listed as Least Concern by the IUCN Red List of Threatened Species. Reports are increasing of polecat population declines in several countries, although a paucity of data means population trends are poorly understood. This paper reviews and summarises information on the polecat’s status and range-wide population trends. Information and opinion were gathered for 34 countries, from individuals and organisations studying polecats and from reviewing the literature and national Red Lists. Where trends were identified, the polecat population is known or suspected to be declining in 20 countries, reported to be stable in five countries, stable or increasing in one country, and increasing in two countries. For many countries, data are so limited in quantity or spatial scale, or at risk of bias, that trends could not be identified or confidence in trend assessments is low. The main drivers of polecat decline are poorly understood, but might include habitat degradation; changes in prey availability; competition with invasive carnivores; poisoning; conflict with human interests; harvesting and killing of polecats; and hybridisation. Robust survey methods and systematic monitoring programmes are urgently needed to gather up-to-date data on polecat population trends across the species’ range.

Does the American mink displace the European polecat? A need for more research on interspecific competition between invasive and native species

“…The polecat's population dynamics in Europe remain largely unknown. Demographic analyses of local populations come from a variety of sources, such as records of road casualties and sightings (Melero et al 2012;Berzins and Ruette 2014;Croose 2016), winter tracking (Sidorovich et al 2008) and national hunting records (Baghli and Verhagen 2003). However, in general, the existing knowledge is mostly based on sparse data, and recent reviews may have been misleading due to being based on unreliable information (Hofmeester et al 2019).…”

Intra- and interspecific morphological variation in sympatric and allopatric populations of Mustela putorius and M. eversmanii (Carnivora: Mustelidae) and detection of potential hybrids

“…They form the most clearly defined species group of the genus Mustela (Abramov 2000). M. putorius occurs throughout most of Europe from the Great Britain to the Ural Mountains (Croose et al 2018) with an unclear eastern border in the European forest-steppe zone (see Fig. 1).…”

Harmonizing hybridization dissonance in conservation

“…behavior of wildcats 55 , and on the fitness of the polecat population 88 , deserve more attention before rejecting hybridization as a threat or proposing it as a conservation management tool.…”

“…While the phenotype of Scottish wildcats has been seriously affected 86 , the polecat phenotype has been much less affected due to hybridization 87 . In both cases, the increased genetic diversity may have a positive effect in front of changing environmental conditions, but the impact of hybridization on the behavior of wildcats 55 , and on the fitness of the polecat population 88 , deserve more attention before rejecting hybridization as a threat or proposing it as a conservation management tool.…”