When you pass through the main entrance of Oakland Zoo, the first species you are greeted by are the colorful and charismatic lesser flamingos. A favorite to many, zoos offer a chance for people to come and see species like these that they may never have had the means to see otherwise. It is through opportunities like these that zoos work to inspire people to learn about and act to save threatened animals. However, an additional goal of the zoo that many visitors may not be aware of occurs behind-the-scenes and that is to be a site for animal behavior and welfare research that might otherwise be impossible to complete.
Oakland Zoo’s flock of lesser flamingos. Photo by Natasha Tworoski
Doctoral candidate Paul Rose of the University of Exeter reached out to zoos worldwide to create a photo database to decipher how important individual relationships are between members of a flamingo flock. Since zoos use numbered ID bands to keep track of individuals in their collection and we can get much closer to our captive flock than a researcher would be able to a wild one, zoo flamingos offer a great alternative for a study like this. Something that makes our Oakland Zoo flock particularly special? All 16 members are males, which may or may not have an effect on how our birds form relationships.
For six months, Oakland Zoo keepers took pictures of our flamingos three times a day, four days a week to send to Paul for analysis. While this information is valuable from both a theoretical and conservation standpoint, it can also be useful information to those of us caring for the individuals. Like all of us, sometimes our flamingos can get sick or have minor injuries which requires them to spend some time at our zoo’s hospital while they mend. Being social animals, we always make sure to send a few extra flamingos with, so the patient feels more comfortable while he heals. Knowing who is friends with whom among our flamingo flock makes us better zookeepers and prevents us from breaking up important relationships that are a natural part of their life cycle.
ID bands are placed on the legs of Oakland Zoo’s flamingos to make it easier for zookeepers to track individuals. Photo by Natasha Tworoski.
While Paul will be continuing to collect more data before drawing any conclusions on flamingo relationships, we asked him to share with you a description of his study and why he is asking the questions he is about flamingo friendships. Meanwhile, the keepers may need to consider if they should trade out the numbered ID bands for friendship bracelets.
Paul Rose, flamingo researcher collaborating with Oakland Zoo.
I have been conducting zoo research since completing my undergraduate thesis in 2002, and have always been keen to learn more about zoo animal welfare and how to improve the lives of animals housed in the zoo. I have had a special interest in husbandry and management of giraffe and flamingos, as these can be often “overlooked” in the world of research and scientific investigation. As a member of the UK’s zoo research committee, I help to advise the Bird Working Group. As well as “in zoo” groups, I also have a role on the International Union for Conservation of Nature (IUCN) Giraffe & Okapi Specialist Group and on the Flamingo Specialist Group. I have been investigating the social lives of flamingo since 2012. As one of the commonest of zoo-housed animals, flamingos are an excellent candidate for research into how captivity affects animal behaviour, as the results of such studies have wide application to many hundreds of individuals. Alongside of this PhD work, I also teach university students in animal behaviour and welfare, and conservation.
Flamingos are one of the world’s most gregarious animals. Flocks numbering over two million birds have been recorded, suggesting that relationships between individual flamingos may be important and may have a role in flock structure. It is important to note that gregarious and social can be two different things, and a defined social structure could be missing from these large flock of birds. By defined social structure, think about the hierarchy and highly structured relationships that exist in a troop of gorillas, for example. Research on wild flamingos has posed the following question; because all six flamingo species occur in potentially highly coordinated, highly social groupings, maybe more is drawing them together than simply access to resources found in only one place? The complex displays of the flamingo, as well as its bright colours and range of vocalisations that the birds appear to use to organise themselves, are suggestive of a complex and highly-ordered society where individuals have a specific role or function within the flock.
Flamingos feeding together in the water on exhibit. Photo by Colleen Renshaw.
Like the fission-fusion systems seen in some primates, for example baboons, flocks of flamingos move around in smaller groups that come together when the whole flock needs to perform specific actions as a collective (for example when travelling, courtship display and nesting). Such bonded birds often file around after each other or move together in parallel, demonstrating the strength of their partnership. A useful metric to use is a flamingo’s neck length. If one bird allows another into this space, it is suggestive of a stronger, more important relationship. By watching a flock of resting or preening flamingos, it is easy to spot these smaller friendship groups based on the distances relative to each other when compared to other groups within the same flock.
Observing flamingos within a zoological collection can add vital, new information to our grasp of what may be going on in wild flocks, and enhance our knowledge of a flamingo’s friends and relationships. Large groups of flamingos provide a natural setting for close-up documentation of connections between birds. The flamingo flock is a soap opera of arguments, fallings-out, squabbles, marriages, divorces and cliques. New scientific techniques, developed in the field of human psychology can provide a deeper understanding of how these aspects of flock activity play out and affect the fortunes of each individual bird. Termed “social network analysis” these methods provide a pictorial overview of the connections that each bird has, to others, in the group that it lives. By assessing such connections, we can de termine who influences the decisions that individuals make in a flock as well as understanding the quality of life each bird experiences (and how this quality of life is influenced by the birds that it lives with). The lives of wild flamingos can be tricky to follow, although there are some long-running projects out there on wild birds, so by watching the behaviour of captive birds, we get a good idea of how and why flamingo social behaviour works in the way that it does.
Lesser flamingos are considered to be a “Near Threatened” species by the world’s conservation union. They are in trouble in their natural environment due to human pressures on their unique habitat. Zoo-housed lesser flamingos can tell us a great deal about the ecology of the species overall, and if strong relationships exist between captive birds, this may be suggestive of a much more stable, much more structured social system in wild flocks too. Therefore it would be important to manage the long-term environment for lesser flamingos so that when birds move around, and move around with their friends, they are able to be in the same place at the same time and do the same thing as those other birds that they prefer to associate with.
Paul is collecting data from zoos across the globe in order to better understand how these birds form friendships.