Parrots are usually systematically hand-reared to satisfy the pet trade demand, in spite of the exact consequences of hand rearing on the parrots’ behaviour still remain inaccurate and unclear. The objective of this case study is to investigate how hand-reared, parent-reared and wild-caught African grey parrots (Psittacus erithacus) vary in their behaviour.
In addition, the hand-raised parrots were divided into different categories to examine the impact of the different hand-rearing methods on the birds’ behaviour. A questionnaire containing 199 multiple-choice questions about the breeding method, care, housing, health, origin, previous owners, behaviour and social interactions was administered to owners of 103 grey parrots which were at least 3 years old and whose origins were known. The breeders of the captive-bred birds were also interviewed and were asked 11 questions regarding the incorporated hand-rearing method. To avoid bias, all subjective responses were checked and adjusted using objective components.
The results show that hand-reared parrots were more aggressive and more selective (p = 0.008, X2 = 9.72) towards humans than the naturally reared birds. Moreover, the adult hand-reared parrots besought to have food more often (OR = 3.93, R2 = 0.46). The hand-reared chicks which were below 5 weeks old when removed from the nest developed stereotypies more often than the chicks that remained longer with their parents (OR = 8.98, R2 = 0.54). The hand-fed using tubes chicks were more aggressive (OR = 5.09, R2 = 0.77) and were in poorer health (p = 0.027, X2 = 5.82) than the birds which were fed using syringes or spoons.
Wild-caught parrots picked their feathers more often (OR = 2.59) had poorer health (p = 0.006, X2 = 7.51) and had usually developed phobic behaviours more (OR = 2.90, R2 = 0.29) than parent-reared or hand-raised birds. To sum up, the results show that the breeding method has a significant impact on grey parrots’ behaviour.
Hand-reared parrots tended to turn out more problematic once adult than parent-bred and wild-caught birds.