Abstract
There are a limited number of studies dealing with abnormal behavior in caged birds kept as pets. However, these studies demonstrate the presence of abnormal behavior in both songbirds and parrots. Ethological studies on these birds, as well as studies on domestic and zoo birds, indicate that inappropriate rearing and housing conditions may lead to behavioral abnormalities. Together these data indicate that behavioral abnormalities occur among both wild-caught and domesticated pet birds. The severity and magnitude of these abnormalities is probably underestimated, and there is a need for systematic studies on the nature, origin, variability, species-specificity, and reversibility of behavioral problems in pet birds. Abnormal behavior in caged birds may to some extent be prevented and reduced by environmental enrichment. However, most enrichment studies are anecdotal and not based on a thorough analysis of the behavioral abnormalities, which may lead to measures resulting in a reduction of symptoms rather than the underlying causes. Although it is likely that several of these problems could be reduced by modifying rearing and housing conditions, the current insights into the causal mechanisms underlying abnormal behavior of domesticated and wild-caught pet birds are limited, as are the insights into the possibilities of preventing or curing abnormal behavior.