The effect of conspecific attraction through song playback on a songbird community
The presence of conspecifics is an indicator of good habitat for a number of songbird species. Thus, playback of male birdsong as an indicator of conspecific presence has become a successful tool for attracting songbirds to specific, pre-selected sites of high-quality habitat. Previous studies have used conspecific playback to encourage the establishment of a single endangered and threatened species. However, ecological management agencies are increasingly interested in developing multi-species programs that improve habitats for an entire community of species. Yet, empirical studies employing the playback of songs from multiple species are absent, and only a few studies have investigated the effects of conspecific playback on non-target species. It is possible that some non-target species are repelled from areas of playback; potentially resulting in an unintended but negative impact on the greater community. In light of these concerns, we investigated whether six common, migratory songbird species in forested regions of Northern Michigan are more likely to use habitats and establish territories near playback speakers in response to simultaneous playback of songs from each species. To evaluate the effect on the greater songbird community, we assessed habitat use and territory establishment in twenty-two non-target species within the areas affected by song playback.
As a group, our six target species were more common and established more territories near playback speakers. Three of our six target species increased their use of areas near playback, and the remaining species were relatively unaffected by playback, experiencing no decrease in use or territory establishment within playback areas. These results suggest that conspecific attraction can be used to attract multiple songbird species simultaneously, a benefit for programs aimed at increasing habitat use beyond a single species. Further, in targeted projects, playback of secondary species of importance may reduce the likelihood of negative competitive effects. However, several non-target species in this study were less likely to establish territories near playback speakers. Phylogenetic comparisons revealed that the species most closely related to our playback species were those most likely to be impacted. While our results reinforce the overall value of conspecific playback as a management tool, we suggest that its impact on non-target species should be considered before implementation.