Pet bird caging — social by nature; solitary small cages harm welfare
Source: Merck Veterinary Manual (merckvetmanual.com), a copyrighted professional veterinary reference. Per COPYRIGHT_POLICY §3, the points below are paraphrased derived fact summaries: numerical values and proper nouns are preserved from the source, but sentences are rewritten and not quoted verbatim.
Claims
*[Paraphrased derived summary — non-Open-Access source.]* Pet birds are intelligent and social animals adapted for flight. *[Paraphrased derived summary — non-Open-Access source.]* Keeping solitary pet birds in small indoor cages, with limited opportunity for exercise, has both physical and psychological consequences.