The study on the reproduction parameters of Arctic foxes was conducted on a farm located in north-eastern Poland, in the years 2000-2002. Three genetic groups were distinguished: group I – Finnish foxes (F), group II – F₁ hybrids (F × P), group III – Polish foxes (P). Finnish foxes (FF – Super blue) were descended from the ones imported from Finland. F₁ hybrids were produced by mating Finnish foxes to Polish ones. Group III were Polish foxes mated within the population. The reproductive activity of males was analyzed on the basis of the number of matings over the breeding season. In the case of females the parameters taken into account were: the percentage of barren females and fecundity, i.e. the number of pups born alive and weaned. It was found that the reproductive activity of Finnish and hybrid males was higher than the activity of Polish males. The percentage of barren females was higher in the group of one-year-olds, compared with the ones used in successive years. The fecundity of Finnish and hybrid females displayed a falling tendency.

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