Effects of colour bands on male competition and sexual attractiveness in zebra finches (Poephila guttata)

Abstract

Recent work suggests that coloured plastic leg bands may alter the sexual attractiveness and reproductive success of zebra finches (Poephila guttata). For example, males wearing red bands are more attractive to females and have enhanced reproductive success compared with males that have light green bands. Colour bands have been widely used in studies of avian behaviour and therefore could introduce bias if they regularly have a significant impact on social interactions among individuals. We carried out an experiment to assess the proximate effects of colour bands on zebra finch behaviour. Male zebra finches maintained in a large indoor aviary were given either red or light green bands and then scored for their ability to compete for a limited number of nest boxes and to attract females. The same males were randomly reassigned either red or light green bands and tested for their ability to regain boxes and attract new females. We found no correlation between band colour and a male's ability to gain either a nest or female. However, there was an association between male activity level and success. Also, those males that attracted a female in the first part of the experiment were more likely to do so in the second part of the experiment. We conclude that any immediate advantages conferred by attractive band colours may be masked under conditions of strong intermale competition for nests and mates.