California's urban crow population is getting out of hand in many places, but now something can be done about it. An audiotape with the distressed "caw"-ry of Corvus brachyrhynchos -- the American crow -- has been released through the UC Division of Agriculture and Natural Resources, offering a safe and effective way to drive away the pesky birds. The distress call tricks the birds into thinking one of their group is being attacked by a predator. Packaged together with a leaflet, the tape gives valuable background information about where, why and how crows roost, their diet, range and other important crow facts. "Crow roosts can be major nuisances around residential areas, shopping centers, office complexes, and anywhere else people live, work and play," says Paul Gorenzel, a UC Davis wildlife biologist who has studied the problem and developed the package. The audiotape, which costs $10.50 plus shipping and handling, requires no specialized equipment or federal, state or local permits.