Playback experiments were conducted with a pack of captive Iberian wolves. We used a habituation–discrimination paradigm to test wolves’ ability to discriminate howls based on: (1) artificial manipulation of acoustic parameters of howls and (2) the identity of howling individuals. Manipulations in fundamental frequency and frequency modulation within the natural range of intra-individual howl variation did not elicit dishabituation, while manipulation of modulation pattern did produce dishabituation. With respect to identity, across trials wolves habituated to unfamiliar howls by a familiar wolf (i.e., no direct contact, but previous exposure to howls by this wolf), but not to unfamiliar howls from unfamiliar wolves (i.e., no direct contact and no previous exposure to howls by these wolves). Modulation pattern seems to be an important bioacoustic feature for individual recognition. Overall, our results provide the first experimental evidence that wolves can discriminate individuals based on the acoustic structure of their howls.
Sousa-LimaR.S.PagliaA.P.Da FonsecaG.A.B. (2002).
Signature information and individual recognition in the isolation calls of Amazonian manatees, Trichechus inunguis (Mammalia: Sirenia). —