Five mustelid species were found in the Ciemna Cave, in layers 13-1 dated at MIS 5-1: Gulo gulo, Meles meles, Martes martes, Mustela erminea and Mustela nivalis, with the remains of M. martes being the most abundant. They were represented almost exclusively by cranial material, mandibles and isolated teeth. Metrically and morphologically most of the remains corresponded to the modern European forms. Only few isolated teeth of M. martes belonged to a great, robust form which was characteristic of cooler phases of the Late Pleistocene and beginning of the Holocene. Another cold-adapted mustelid, represented by a single, damaged calcaneus, was G. gulo. Few bones showed traces of carnivore activity, which can be regarded as one of the accumulation factors, other possible factors being water and accidents. [ABSTRACT FROM AUTHOR]