Psychological stresses are very real and threatening to birds. Other psychological stresses can result from a bird's physical environment. Strange sounds, new people or pets, changes in diet and moving to a new cage, room or house can all act as stressors. Abrupt changes in temperature or humidity can also stress a bird. People who keep their pet birds up until all hours of the night, disrupting normal sleep patterns, also create stress for their birds.
Separation anxiety is one stressor that warrants mention.
People often ask us if it is more stressful to take pet birds on vacations and business trips than to leave them at home with a pet-sitter. That, of course, varies from bird to bird. Some birds freak out around cars, planes, hotel rooms and strange cages, but others mourn if separated from their beloved owners. Birds that have bonded intensely with their owners probably suffer less stress when accompanying their owners on vacation, if hotels and travel parks allow them. If you do travel with your bird, make sure you have necessary health certificates, and check ahead of time whether or not your bird can legally enter the states you pass through.