BOWER DESTRUCTION, DECORATION STEALING AND FEMALE CHOICE IN THE SPOTTED BOWERBIRD CHLAMYDERA-MACULATA

Male bowerbirds build and decorate bowers to attract females as copulation partners. Here we report the first information on the relationship between the bower and mating patterns in the Spotted Bowerbird Chlamydera maculata. The mating success of male Spotted Bowerbirds is correlated with the quality of male bowers and several measures of bower decoration. Bower destruction and decoration stealing are rare. The low rate of interaction among bower holders appears to result from the large distances between bowers. Studies of the Satin Bowerbird Ptilonorhynchus violaceus have shown a much higher level of stealing and destruction and support the view that male interactions are critical in determining the level of bower decoration and bower quality (Borgia 1985b; Borgia & Gore 1986). The low levels of stealing and destruction in Spotted Bowerbirds, coupled with the correlation of bower quality and mating success, suggest that high levels of male interaction are not a necessary prerequisite for females to use bowers as a factor influencing mate choice. We consider the implications of this finding in regard to the evolution of bower building and the evolution of sexual display.