Abstract Polecat populations show a very low genetic diversity and a high inbreeding coefficient. Furthermore, the estimate of effective population size is alarmingly low. Polecats Mustela putorius populations are structured into scattered breeding sub-units usually made up of one male and two females, according to a polygynous mating system. Because a strict spatio-temporal segregation was observed between males and females, we propose to call individualistic such species. We suggest that the solitary habits of individualistic species may result in or worsen a high inbreeding and exacerbate their conservation issue, a crucial perspective for critically endangered species such as the European mink
