The European mink is a critically endangered mustelid species of conservation concern throughout Europe. Several conservation interventions have been implemented in recent years, supported by both national and European governments. However, knowledge about the natural history of the European mink is scarce and localized to a few specific areas. From 2007 to 2009, we studied mink activity patterns, home range sizes, and macrohabitats of mink home ranges based on 28 radio-tracked European mink (10 adult females, 11 adult males, 3 young females, and 4 young males) in the Foral Community of Navarre (northern Spain), in the Arga and Aragón rivers. We also provide insights on the spatial organization of the species. European mink presented a stable, mainly nocturnal and crepuscular activity pattern and required between 15 and 75 ha of fluvial habitats to establish their home ranges, which were also quite stable throughout the year. There were great differences between adult females and adult males, the latter having home ranges five times larger. In addition, whereas adult females mainly settled in lagoons and small tributaries, males also used to a large extent the main river sections. European mink presented a polygynous mating system, where males were territorial and encompassed several female home ranges within their home ranges. Lagoons and similar structures should be preserved and favored in management strategies, and tributaries maintained in good condition, as female requirements should be prioritized in plans to improve the general habitat quality for the species. Any conservation plan aimed at the improvement or recovery of European mink populations through habitat management should consider management blocks of at least 15 ha per each potential breeding female.

Trabajo presentado al: XI Congreso de la Sociedad Espanola para la Conservacion y Estudio de los Mamiferos (SECEM) (Aviles, Asturias, 5-8 diciembre, 2013).

1 pagina.-- Trabajo presentado al 35eme Colloque Francophone de Mammalogie: les mammiferes dans les ecosystemes aquatiques. (Arles, Bouches-du-Rhone, France. 19 au 21 octobre 2012)

Despite the numerous studies carried out on the endangered European mink (Mustela lutreola) for conservation purposes, the reproductive biology of this species is largely unknown. In the wild reproductive parameters such as litter size are difficult to observe, particularly for cryptic species such as mustelids. We compared the reliability of nonstained and stained placental scar counts in farmed American mink (Neovison vison) with known litter sizes and then applied the best methodology to free-ranging related species-European mink, European polecat (Mustela putorius), and feral invasive American mink-for a comparative study of embryonic litter size in western Europe populations. The staining method allowed us to improve the detection of placental scars and to increase the reliability of the method by reducing the observer effect. Nevertheless, this analysis must be performed by 7 months postpartum, before the regeneration of uterine tissues. In free-ranging animals the mean embryonic litter size, estimated by stained placental scar counts and embryo counts, was significantly lower in European mink compared with polecats and American mink, and in polecats compared with American mink. Small litter sizes in European mink could be a factor limiting population growth rates in the species. Our results constitute a first step toward demographic analyses aimed at modeling the population dynamics of these species. DOI: 10.1644/09-MAMM-A-297.1.

Serious declines in populations of native European mink (Mustela lutreola) have occurred in Europe. One responsible factor may be infectious diseases introduced by exotic American mink (Mustela vison). In order to investigate a possible role for Aleutian mink disease parvovirus (ADV), we surveyed native riparian carnivores and feral American mink. When serum samples from 12 free-ranging European and 16 feral American mink were tested, antibodies to ADV were detected from three of nine European mink. ADV DNA was detected by polymerase chain reaction in whole cell DNA from four of seven carcasses; two American mink, one European mink and a Eurasian otter (Lutra lutra). Lesions typical of Aleutian disease were present in one of the American mink. A portion of the ADV VP2 capsid gene was sequenced and the results suggested that two sequence types of ADV were circulating in Spain, and that the Spanish ADVs differed from other described isolates from North America and Europe. Future conservation and restoration efforts should include measures to avoid introduction or spread of ADV infection to native animals.