Mere fear shrinks bird families | Science News

SCIENCE NEWS NEEDS YOU

Support nonprofit journalism

Subscribe now


News

Mere fear shrinks bird families

Just hearing recordings of predators caused sparrows to raise fewer babies

By
2:03pm, December 8, 2011

Nothing but fear itself can actually be dangerous for nesting birds.

Song sparrows protected from attack but subjected to recordings of predator yowls and leaf-crunching approach noises raised 40 percent fewer offspring in a year compared with neighbors living amid innocuous noises, says population ecologist Liana Zanette of the University of Western Ontario in Canada. Predators do not need to kill a single prey to have a big effect, she says.

Scary noises, broadcast where the sparrows nested in the wild, took a toll throughout the breeding season, Zanette and her colleagues report in the Dec. 9 Science. The alarmed sparrows laid fewer eggs to begin with, and they proved such

This article is only available to Science News subscribers. Already a subscriber? Log in now. Or subscribe today for full access.

Get Science News headlines by e-mail.

More from Science News

From the Nature Index Paid Content