COMPARISONS OF THE VOCALIZATIONS AND SOCIAL-BEHAVIOR OF SOUTHERN AFRICAN PYCNONOTUS BULBUS

Vocalizations and associated behaviour of three Pycnonotus species are described, based on field observations and tape recordings from which sonagrams were produced. These species, which are locally sympatric a nd hybridize, have similar vocalizations and displays; differences are most apparent in their contact calls and songs. Quantitative analysis of the songs showed that P. barbatus and P. capensis are easily disti nguished, whereas the song characteristics of P. nigricans overlap tho se of both the other species. Playback experiments with territorial ma le P. barbatus in an area of allopatry showed similar responses to son gs of conspecifics and of P. nigricans, but almost no response to the song of P. capensis.