Budgerigars, canaries, and other small cage birds are extremely popular pets globally. Their welfare in typically small cages is often poor, despite their common status making welfare concern seem unnecessary.
Most pet budgerigars, canaries, and finches are kept in conditions that prevent flight — the defining behaviour of their order. A bird that cannot fly is physiologically and behaviourally deprived in a fundamental way. Standard cages prevent flocking in species that evolved in large social groups. Seed-only diets cause nutritional deficiency, obesity, and liver disease. Feather ruffling, head-bobbing, and repetitive perching movements are stereotypic behaviours common in poorly housed cage birds. The perception that small birds require minimal care creates a welfare gap between their actual needs and the conditions most are kept in. Aviary keeping, social housing, and dietary variety significantly improve cage bird welfare.