SONG SWITCHING IN MONANDROUS AND POLYANDROUS DUNNOCKS, PRUNELLA-MODULARIS

The dunnock song repertoire comprises multiple song types, and during bouts of singing males repeat a song type several times before switchi ng. Several hypotheses suggest that the rate at which males switch son g types may function in male-male aggression, mate attraction, or both . Dunnocks switched song types 10 times faster when searching for a re ceptive female than during male-male interactions. Polyandrous and pol ygynandrous males switched song types significantly faster than monoga mous and polygynous males when separated from a fertile female, but th ere was no difference in switching rates during song duels or spontane ous song bouts outside the fertile period. Thus males were more likely to switch song types if they were competing to attract a receptive fe male than if they had exclusive access to females. Contrary to the pre dictions of the anti-exhaustion and anti-habituation hypotheses, the r ate of song switching was higher in the contexts in which song rate wa s slower. (C) 1997 The Association for the Study of Animal Behaviour.