Birds Settle Where They’ll Have Company

Birds check out the chicks before they move to a neighborhood--assessing how many nestlings there are in the homes of older residents, researchers report. When researchers stole baby birds from nests in one area, new birds avoided moving there and some birds left, the researchers report in Friday’s Science. This shows that counting chicks may be a shortcut for birds trying to figure out the best places to live, according to Blandine Doligez of the University of Bern and her colleagues.

Working on the Swedish island of Gotland, Doligez and colleagues manipulated the nests of collared flycatchers--migrating birds that live in holes in trees. They moved baby birds from nests in one plotted area to nests elsewhere. “We tried to mimic predation,” Doligez said in an interview. “This sometimes happens in this population.”

Sure enough, birds moved away from areas where the young were stolen and moved to areas where baby birds were added to nests.