The influence of photoperiod on male courtship and nest-building in the Ring dove, Streptopelia risoria

The aim of this study was to examine the influence of photoperiod on the hormonal induction of courtship and nest-building behaviour in the male ring dove (Streptopelia risoria). In the first experiment 24 intact males were divided into two groups and held on long (16L:8D) or short (8L:16D) photoregimes for five weeks. They were then paired with intact females and their behaviour recorded. Long day males exhibited significantly higher levels of bowing and nest-soliciting. In the second experiment males were again held on long or short photoperiods. Half of each group received daily injections of testosterone propionate. Testosterone treatment eliminated differences in courtship between the two groups, but nest-building remained significantly higher in hormone-treated long day birds. The experiment was then repeated using TP-treated castrates. In this case courtship did not vary between long and short groups, although nest-building was still greater under the long photoregime. These results indicate that photoperiod alters male courtship by stimulating endogenous androgen production. The influence on nest-building, however, appears to be least partially dependent upon some other mechanism.Science, Faculty ofZoology, Department ofGraduat