Vulturine guineafowl forage predominately on glades (open grassy areas) in the morning and afternoons. Here, their large numbers provide them with many eyes to look out for predators.
Understanding the collective behaviour of guineafowl Vulturine guineafowl live together in large groups, and these groups form part of a large and complex society. Researchers in the ECOLBEH project are looking at how these animals deal with the challenges of living in such a society, and how doing so can help them survive the harsh Kenyan climate, as Prof Dr Damien Farine explains. The vulturine guineafowl is a highly social species of largely land-based bird endemic to East Africa, where they live together in groups of between 15-60 individuals. While the main advantage of this behaviour is that it provides a degree of protection from predators, there are also other benefits. “The birds are likely to benefit in terms of finding food and water, navigating the landscape, and so on,” explains Prof Dr Damien Farine, Scientist at the Max Planck Institute of Animal Behaviour, Eccellenza Professor at the University of Zurich, and Associate Professor at the Australian National University.
Making decisions as a group As the Principal Investigator of the ECOLBEH project, Prof Dr Farine is studying the ecology of the collective behaviour of vulturine guineafowl. This involves looking at how these animals function as a group, for example how they decide where to go when group members have
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different preferences. These birds live together in very stable groups, so they somehow must reconcile their differences and come to an agreement about what to do next. “What we found is that they use very simple rules, akin to voting: any group member can initiate movement, and the group follows the direction of the majority,” says Prof Dr Farine. His study, based at the Mpala Research Centre in Kenya, relies primarily on using GPS tags to collect precise information on where each group – or in some cases each member of a group – has travelled over time. By putting GPS tags on all individuals from the same group, the research team can collect a wealth of information on where each group member is, as well as how they move relative to each other. “From this information, we could see that the group make democratic decisions – they essentially vote on where to go next,” says Prof Dr Farine. “However, not all individuals have equal influence – most of the time (but not always!) it is the males that decide.”
members, and we can say where that group has been from the GPS tags,” he outlines. By combining the large-scale deployment of GPS tags across all of the groups in the population with repeated observations of individually-marked birds within each of the groups, Prof Dr Farine and his colleagues have been able to gain fresh insights into the behaviour of vulturine guineafowl. “We’ve been able to show how each group moved and interacted with other groups, and how the membership of each group has been very stable over several years,” he says. “Groups also contain multiple males and multiple females, all of which can breed if the conditions are right, which again is unusual among birds.” The project’s research has also yielded new information about other aspects of these birds’ behaviour. Researchers have found that young males in a group will help their mothers with raising the next generation of offspring, and that there are strict dominance hierarchies. “The males in particular have a clear alpha, beta, and so on. When interacting with each other, individuals are very strategic, investing only in fighting with their closest competitors for rank,” says Prof Dr Farine. These patterns in social structure within groups and across the population raise questions about how this kind of society has evolved, and whether it reflects similar challenges faced by other species that
evolved in the same environment. “It also gives us an opportunity to gain insights into how such animal groups – which includes many primates – solve some of the challenges associated with living in large, stable groups,” continues Prof Dr Farine.
away from Mpala together to go in search of resources,” continues Dr Farine. “An exciting question we’re trying to answer next is to determine how groups know where to go.” One hypothesis is that the females know where to go, as when they come into a group
We’ve been able to show how each group of vulturine guineafowl moved and interacted with other groups, and how the membership of each has been very stable over several years. Groups also contain multiple males and multiple females, all of which can breed if the conditions are right Dealing with drought Recently, Prof Dr Farine’s study area has experienced one the most severe drought in half a century. This dramatic change in conditions has allowed researchers to understand how living in a group and forming a multi-level society helps these birds deal with the environmental challenges of living in a semi-arid landscape. The droughts have forced groups to leave their regular home ranges at Mpala in search of food, yet Prof Dr Farine says it can be difficult for the birds to know where to look. “Because group members stay together all of the time, the information that they have about their landscape is limited,” he explains. One way the birds solve this challenge is by joining up with other groups. “We’ve seen up to four groups making large movements
they also bring their prior knowledge, which may include an awareness of food sources. However, Dr Farine says that testing this hypothesis is quite challenging. “We don’t know where the females have come from before they enter our population,” he explains. “In future we hope to increase the scale of our tracking to multiple populations to also capture the movement of female guineafowl as they move from group to group.”
Female dispersal Another topic of interest is looking at how females decide on where to go when they leave their groups in search of new ones, and how they achieve the transfer to a new group. The research team has found that females can move relatively long distances to find new groups in completely
Vulturine guineafowl live in a multilevel society. These are societies in which individuals form groups (coloured circles), and those groups then interact with other groups — with preferences for specific groups as shown by the connecting lines in this group-to-group network. Prior to the work on vulturine guineafowl, such societies were thought to exist only in mammals, including humans, primates, and giraffes.
An unusual multi-level social structure As the first project ever conducted on this striking species, and one of the very few behavioural studies ever conducted on any guineafowl, Prof Dr Farine was also excited to gain some new insights into their social systems. Almost immediately, the team made a startling discovery. “We found that groups sometimes come together with other groups to form super groups. This is quite unusual among birds and it has some similarities to primates and other large mammals that live in so-called multi-level societies,” outlines Prof Dr Farine. This unexpected social structure for birds has been uncovered thanks to Prof Dr Farine’s work in tracking the movement of several groups of guineafowl. “Every group in the population we’re looking at has between 2-6 GPS-tagged birds, and every member is marked with a unique combination of colours on its legs. This allows us to identify all the
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