Oct. 16, 2013 — In the forests of Ecuador, plain-tailed wrens nest in bamboo thickets, singing complex and continuous melodies. Residing nearby are rufous antpittas, small, secretive birds that hop like thrushes and whistle in mossy forests. Together, their songs fill parts of the South American Andes.
Birdwatchers often seek out rare and beautiful birds like the wren and antpitta using "playbacks" -- or recordings of bird songs -- to draw such them out from their hideaways. But does such babbling-on-repeat harm the birds?
Using the emphatic sounds of both bird species, a Princeton University researcher has -- for the first time in peer-reviewed research -- examined the effects of birdwatchers' "playbacks" in the wild. In PLOS One, he shows that playbacks do have potentially negative consequences, especially in terms of birds' energies.
"Playbacks would be harmful if a species becomes stressed, expends energy, or takes time away from other activities to respond to these recordings," said J. Berton C. Harris, a postdoctoral fellow studying under Professor David Wilcove from the Woodrow Wilson School of Public and International Affairs' Program in Science, Technology and Environmental Policy.
Working in a southern Ecuadorian biological reserve, Harris studied the effects of both single and repeated playbacks on wrens and antpittas. In his first trial, he introduced single playbacks to 24 groups of wrens and 12 groups of antpittas. Along with David Haskell from the University of the South in Tennessee, Harris monitored both bird species for one hour after playing a five-minute, self-recorded song.