Dam Good Friends

Beaver dams are a boon for migrating birds

• Hannah Schardt
• Feb 01, 2009

SOME HUMANS consider beavers pests, especially when the animals’ dams flood property. But for several species of migratory songbirds, particularly those in the semiarid West, the busy rodents are important allies.

A new study by the Wildlife Conservation Society finds that beaver dams create ponds and encourage the growth of streamside vegetation—all vital to the survival of migratory birds. According to the study, songbird populations became more abundant and diverse when beavers, which study coauthor Steve Zack calls “essential ecosystem engineers,” built more dams in local waterways.