Over the past few years, the crows in much of the Eastern United States fell silent. Many of the birds were victims of the emerging pathogen called West Nile virus. Originally from Africa, the virus entered the United States only a few years ago and is now spreading across the country in migrating birds (SN: 12/11/99, p.
Log in
Subscribers, enter your e-mail address for full access to the Science News archives and digital editions.