Jacinta Bowler
You might be an expert in chicken emotions and not even know it.
A new Australian study has found humans are surprisingly good at discerning chicken calls, particularly whether they were about to be rewarded with a treat or were just having a normal day.
The research has been published in Royal Society Open Science.
To work this out, first the team had to make some hens happy. They took twelve 18-week-old ISA Brown hens, and started training them to expect food after a certain noise – called Pavlovian conditioning.
They noted calls from when they were about to receive a reward, or during control treatments that were not reward related.
The team categorised these calls as the ‘food’ call and the ‘fast cluck’ when the birds were soon to receive food, and the ‘whine’ and ‘gakel’ call (a special call indicating frustration in laying hens) when they were in non-reward contexts.
The researchers took audio of these calls collected in an earlier paper and then put 194 humans to the test.
“Participants listened to 8 calls when chickens were anticipating a reward, and 8 calls in non-rewarding contexts, and indicated whether the vocalising chicken was experiencing pleasure [or] displeasure, and high [or] low excitement,” the researchers explain.
They found 69% of participants correctly separated reward and non-reward calls, and were slightly better at categorising reward-related calls overall.
The study adds to a long line of research showing humans are pretty good at understanding emotions across the animal kingdom.
“These studies suggest that there are cross-taxa similarities in how emotions are conveyed acoustically and perceived across mammalian groups, and these allow humans to correctly assign emotional contexts to calls produced by other species,” they write.
“There is some evidence for this in more distantly related species, including birds, reptiles and amphibians.”
The researchers believe their study is important for improving animal welfare within the poultry industry.
“A substantial proportion of participants being able to successfully recognise calls produced in reward-related contexts is significant,” said Professor Joerg Henning, a veterinary epidemiologist from the University of Queensland, who oversaw the study.
“It provides confidence that people involved in chicken husbandry can identify the emotional state of the birds they look after, even if they don’t have prior experience.
“Our hope is that in future research, specific acoustic cues that predict how humans rate arousal in chicken calls could be identified, and these results could potentially be used in artificially intelligent based detection systems to monitor vocalisations in chickens.
“This would allow for the development of automated assessments of compromised or good welfare states within poultry management systems.”