So you want to buy your first cockatiel, here is a guide.
Plumage. The plumage should have some sheen on them, overly fluffed-up birds indicates that it is probably ill, this may be common though during cold weather. The plumage should be smooth and arranged. Falling feathers may be a sign of molting, this is a extremely stressful stage to any bird and their immune system is weak during this period.
Vent. The feathers on the vent area should be devoid of dirt, it is an indication that the bird is suffering from diarrhea or sits on the floor too often.
Posture. A healthy cockatiel will have an alert posture, drooping heads and arched backs are indicators of health problems.
Eyes and skin. Eyes should be wide, full circle and alert, avoid watery or half closed, glassy eyes. Check exposed skins to avoid warts, scaling, boils and the like. These maybe an indication of mites and other bacterial or fungal infections.
Behavior. A healthy cockatiel is alert and inquisitive, the male sings when in the pink of health. Though cockatiels would rather sit and stare, it is agile when in motion, flight is also a good indicator.If you prefer a more domesticated bird, try to hand over a sunflower seed and see if its reaction.
Symmetry. Visually divide the bird vertically in halfand compare one side from the other, the better the similarities of the left to the right side, or vice versa, the better. The cockatiel should walk with complete balance, obese and ill birds would lumber about.
Age. Ask about the age of your cockatiel, purchase a bird not less than three months old. They are able to breed at the age of six(6) months but it is suggested to pair them at one(1) year of age. Cockatiels' average life span is 15-20 years.
Inspect the neighbors, aviary. Observe all the birds in the aviary. A visually healthy bird may show symptoms of illness days after they are broght home due to illness acquired from sick cage mates. Most bacterial diseases are air born so check the whole flock.