Posted: Saturday, July 5, 2008 12:00 am
In OSU study, recorded tweets and chirps get birds to set up housekeeping
By KYLE ODEGARD
Gazette-Times reporter
Birds listen to their elders.
A study by Oregon State University scientist Matt Betts found that some migratory songbirds listen to the songs of older birds - those that have successfully had hatchlings - to remember the best places to live.
This social communication is so strong that Betts played recorded songs and tricked birds to nest in clear cuts and other places they normally would have shunned. The songs were more important than environmental cues the birds could see or smell.
"It's like using word of mouth to find someplace to live, rather than you having to go there and try it out every time," said Betts, an assistant professor in the department of forest ecosystems and society. Unlike humans, birds don't have a long time to live and need to get it right the first time.
Scientists conducted the study on the black-throated blue warbler in the White Mountains of New Hampshire in 2006 and 2007. Recorded songs were played at 54 less-than-desirable sites, but 80 percent of those ended up being settled.
"We always knew communication was important," Betts said. But the study discovered a third and perhaps unintentional role of bird song.
Birds sing to attract mates, as well as to defend and define territory. During the fall, warblers that have successfully mated chirp to their young, probably to teach them how to sing in a way that is, for lack of a better term, "sexy."
But birds moving past eavesdrop and consider those songs of prime real estate.
Betts said he was surprised with how successful his study was.
In the next month or so, he hopes to do similar research on the orange-crowned warbler that lives in Oregon's Coast Range. He wants to trick them from clear cuts to more mature forests, however.
The research about vocal communication in animals could stretch to different groups of species, such as mammals or even frogs, Betts said. Other social cues can be nonvocal, such as scents found in urine.
Scientists at Wellesley College, Queen's University and Trent University in Ontario, Canada also contributed to the research.
Kyle Odegard covers Oregon State University. He can be contacted at kyle.odegard@lee.net or 758-9523.