Peta.org

Life in captivity is frequently a death sentence for birds, who are often lonely and malnourished and suffer from the stress of confinement. Birds are meant to fly and be with others of their own kind in a natural environment. In the wild, these beautiful beings are never alone, and if they are separated from their flock even for a moment, they call wildly to their flockmates. These social animals preen one another, fly together, play, and share egg-incubation duties. Many species of birds mate for life and share parenting tasks. In the wild, most birds will not take a second mate if they lose their first.

Confinement causes birds to have temper tantrums and mood swings. The Los Angeles Times reported that parrots "quickly become frustrated 'perch potatoes' in captivity. ... Many end up obese and with serious behavioral problems such as screaming, biting and self-mutilation by plucking out their feathers." James Serpell, director of the Center for the Interaction of Animals and Society at the University of Pennsylvania, says, "Parrots are the primates of the bird world. They aren't content to sit on a perch and sing."
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