information:classification, information:extraction
Problems and methods of control

Intelligence and social structures make most crow species adaptable and opportunistic. Crows frequently cause damage to crops and property, strew trash, and transfer disease. In densely populated areas around the world, corvids are generally regarded as nuisance animals. Crows are protected in the U.S. under the federal Migratory Bird Treaty Act of 1918, but because of their perceived destructive nature, control of the species is allowed in certain areas. Because of their intelligence, control is often difficult or expensive. Methods for control include hunting, chemical immobilization, harassment and scare tactics, and trapping. Before any measure is used to confine, trap, kill, poison, immobilize, or alter the habits of any wild bird species, a person must check local, state, and federal regulations pertaining to such actions.