These findings may apply to other brainy captive creatures including great apes, elephants and whales, said the head of the research group, Dr Georgia Mason, Director of the University of Guelph’s Campbell Centre for the Study of Animal Welfare.
“This study provides the first empirical evidence that intelligent animals can struggle in captivity,” said Dr Mason, a professor in the Department of Integrative Biology.
"Our findings could help pet owners identify which species may be more challenging to cater for as pets, because of their welfare requirements” added one of the lead authors, Dr Emma Mellor from the University of Bristol's School of Biological Sciences.
The study, also conducted by other researchers at University of Bristol and Utrecht University in the Netherlands, revealed for the first time that this issue can in particular hinder large-brained parrots’ in confinement.
Published recently in Proceedings of the Royal Society B, the study highlights cognitive stimulation and foods that require more complicated physical handling as ways to improve care of birds.
The researchers examined two main data sources. One was an early 1990s survey on captive breeding success involving more than 30,000 birds in the United States. The team also ran an online survey involving almost 1,400 pet parrots in 50 species for stereotypic behaviour: repetitive abnormal activity such as biting at cage bars, chewing or even pulling out feathers, and swaying, bouncing or route pacing in cages.
They looked at housing conditions, brain size-body weight ratios - a marker for intelligence - diets and other factors, and used a form of analysis that allows evolutionary biologists to tease out inherited traits that predispose species to risk.
They found that species whose natural diet involves nuts, seeds and tough-coated insects were more likely to pluck, chew or even eat their feathers. Parrot species with relatively large brains were more at risk for all other forms of stereotypic behaviour.
That finding suggests that owners need to ensure naturalistic diets rather than providing processed foods to pet birds. Wild parrots normally spend 40 to 75 per cent of their active time foraging.
“Parrots may have evolved needs to crunch and manipulate with their beaks – even when their food is ready processed and presented in a bowl. Or they might need particular nutrients present in natural diets. We don’t know which is the most important to feather-plucking birds. So ideally owners should provide naturalistic food items, intact so that parrots really have to break their way in and do extractive foraging for as they do in the wild,” said Dr Mason.
Cockatiels, Jandaya parakeets, and yellow-naped Amazons, for instance, typically thrive in domestic settings. But relatively large-brained parrots such as Nanday parakeets, monk parakeets and some cockatoos suffer more psychological welfare problems. “These intelligent species are more invasive too” added Dr Mason, “which is another reason to treat them with extra care.”
Most parrots are highly social but are often housed alone, and sometimes in monotonous and predictable conditions.
“Some species seem to adapt well to captivity, but maybe some should not be kept unless you have lots of time and creativity,” explained Dr Mason.
She urged owners to provide more stimulation to birds, including more naturalistic aviaries along with puzzles and other enrichment items.
She said: “Good parrot carers are doing this already. But if you’re new to parrots, pick a species likely to thrive. Don’t pick parrots that are not a good fit for your place and lifestyle.”
About half of the world’s estimated 100 million parrots live in captivity, most as pets in private homes. In the wild, more than 40 per cent of species are threatened or near threatened. “It’s really important from a conservation point of view to have good parrot welfare.”
Paper
‘Nature calls: intelligence and natural foraging style predict welfare problems in captive parrots’ by Dr Emma Mellor, Dr Georgia Mason, et al in Proceedings of the Royal Society B