Bird brained behaviour: Cognition and personality in wild pheasants
Published on: 30 June 2016
Professor Joah Madden studies pheasants. This is a bird frequently seen in the British countryside. How many of us have driven down a country lane for what feels like miles, with a pheasant zig-zagging a few feet in front of the car’s wheels?
The pheasant veers towards the verge, but at the last minute the apparently suicidal bird flings itself back into the road, and we continue the game of chase which neither party wishes to play.
So what aspect of these delightful birds does Professor Madden study? Perhaps how a male’s plumage helps him to find a mate – we can all acknowledge their beauty. Or perhaps it's their effects on farmer’s crops? No, it's neither of these - Professor Madden studies their intelligence and personalities.
This work has a number of important implications. It is of interest to the game-shooting industry, where the death of large numbers of birds following release, but prior to the shooting season, is economically, ecologically and ethically damaging. If by making simple changes gamekeepers can improve survival rates, fewer birds will need to be released to sustain a similar level of hunting success.
The research may also provide clues as to how early life experiences influence how personalities and cognitive traits develop in humans.
Professor Madden and his team have even been using pheasants to challenge some basic assumptions on which some commonly used cognitive research tests are based.
It is logical to infer that one individual who outperforms another in a problem solving task possesses some characteristic which makes it better at the task. But is this characteristic cognitive ability? Food is often used as the reward for completing a task. So a hungry bird is presumably more anxious to succeed than a full one?
Scientific methodologies are always designed to control for these effects. But, findings recently published by Professor Madden with Dr Jayden van Horik suggest the factors which mediate motivation and willingness to engage with a task can be more complex and obscure than previously thought. Results showed that an individual’s performance was consistent within the same or similar tasks but not across different tasks. Suggesting it is not possible to say some individuals were generally good or bad at solving such problems.
If such inferences are unsound these findings could have implications for the field of cognitive research.
Captively reared, but wild living, pheasants are a particularly tractable study system in which to address some of the most topical questions in the field of cognitive evolution.
In the UK, more than 40 million pheasants are released every year as gamebirds. These birds are5455 raised in controlled conditions which can be experimentally manipulated. When these birds are released into the wild aged around two months, they can be observed, and their survival and reproductive success recorded.
When I spoke to Professor Madden, an Associate Professor in the University of Exeter’s School of Psychology, he was standing in a field, fixing a hole in the holding-pen containing the pheasants, through which his study subjects were enthusiastically escaping. Despite this, expressing a cognitive coherence and calm personality type to which his pheasants can only aspire, he outlined his research questions and experimental procedure.
Over recent years, he and his team have followed two related research threads. How variation in an individual’s personality (i.e., behavioural traits) and their performance in psychometric tasks, relate to their survival. Second, with collaborators at the Game and Wildlife Conservation Trust, how the conditions experienced by pheasants in early life affect their physical, behavioural and cognitive development and consequently their fate after release.
During the Spring of 2011, Dr Madden and his colleague Dr Mark Whiteside conducted personality tests on 450 young pheasants before they were released onto a shooting estate.
They found that pheasants which were shyer as juveniles survived longer after their release into the wild. Bold males were shot first, and were also more likely to die from disease or predation. Among females, the individuals most likely to die from disease or predation were those who had been shyer as juveniles.
These results show that even apparently unselective hunting can select for particular personality/behavioural traits in released gamebirds.
This begs another question - what causes the individuals to differ? If being bold increases the chances of being shot, why aren’t all birds equally shy? One hypothesis is that the differences evolve because of variations in juvenile experiences.
To investigate this, the team manipulated the diet and spatial complexity of a chick’s early rearing environment. They found that a simple change in diet during their early lives produced complex changes to behavioural patterns, morphological traits and motor skills. They also discovered that the addition of perches in early life had a profound effect on physical and cognitive development, and therefore on chances of survival.
Whether bold and beautiful or shyly scintillating, pheasants brighten the British countryside. And although their personalities and intellectual prowess may seem rather pedestrian by our standards, through some innovative research, we are perhaps learning something from these bird brains about what makes you, you.
This study is part of a five-year project, funded by a European Research Council consolidator award.