Implications of vocalizations during giant panda breeding

Silent most of the year, giant pandas (Ailuropoda melanoleuca) engage in sustained and diverse vocal behavior during their brief annual reproductive window. These vocalizations suggest a complex communication repertoire and play an important role in facilitation of mating. To increase our understanding of their vocal communication, we analyzed male and female vocalizations during breeding interactions. Digital audio recordings were collected during breeding seasons of 2008, 2009, and 2011 at zoological facilities in San Diego, California, and China, and were processed using Soundtrack Pro 2.0 and Raven Pro 1.4 software. Seven types of vocalizations were identified (“bark,” “moan,” “growl,” “squeal,” “chirp,” “bleat,” and “copulation call”). We compared vocalizations from 32 confirmed copulations and 37 non-copulatory breeding sessions of 31 individuals (24 females, 7 males). They revealed differences in vocalizations produced before, during, and after intromission. During intromission, the male produces a copulation call that distinguishes successful breeding encounters from unsuccessful pairings acoustically. This call has not been described previously. The results shed light on the motivational and functional significance of panda vocalizations during mating encounters. They can be used in captive breeding programs to promote reproduction in this endangered species. [Work supported by ZSSD, CSUSM, and CCRCGP.]