Аннотация:Considered extinct in the Iberian Peninsula for seven decades, Pipistrellus nathusii was proven in the 1980s to dwell the Cantabrian and Mediterranean coasts as well as various parts of the Northern Iberian Peninsula during winter. Currently, it is considered a resident of the Peninsula after discovering a summer only-male population in the Ebro Delta (Catalonia). From January to October 2018, we surveyed the species‘ distribution in Cantabria using ultrasound detectors and, where appropriate, the capture of specimens in mist nets. The species identification on sound recordings was confirmed by social calls, following widely accepted scientific criteria. DNA analysis of wing tissue samples from captured individuals was used for taxonomic identification. We confirm the presence in Cantabria of Pipistrellus nathusii throughout the year, both in winter and in summer, the latter settled in several river basins on the northern and southern slopes. This population marks the extreme southwest locality of the range of the species during the summer period. The specimens found on the southern slope represent the highest altitude of a summer colony so far.
