This collection includes information of 2278 records of small mammals distributed in Erro Basin (Navarra) and nearby areas. The study carried out in the basin contributes to the material collection of MZNA with 1798 specimens captured in field and stored in its facilities. The rest of the records correspond to occurrences from field. Material brought to laboratory mainly consists on whole animals (frozen) but there are also skulls, mandibles from barn owl pellets, and skins...