Researchers at a university in Queensland, Australia came across some unexpected setbacks in their planned study when a bunch of magpies chose to remove the tracking devices that had been installed on them. One of the researchers involved in the study wrote a detailed account for The Conversation.
Zoology researchers have relied on tracking devices for decades to gather data about animals they study, their interactions, their whereabouts, and much more. The fitting of the tracking device involves catching the animal of interest, fitting the device, and then letting it out in the wild again.
Coming up with a new tracking device design
However, researchers at the University of the Sunshine Coast in Queensland wanted these tracking devices to be less intrusive and easy to install on smaller birds as well. So, they came up with a different design of these trackers that barely weighed a gram yet could deliver all the desired features of an ideal tracking device such as wireless charging and data transmission.
The researchers even planned an easy removal technique of these trackers in which the tracker would simply unlatch itself in presence of a magnet, completely avoiding the need to capture these birds again.
The research team had planned a pilot study with these new trackers and trained a group of Australian magpies, Cracticus tibicen, to visit an outdoor feeding station. Five birds from the group were captured and fitted with the new trackers.
Scientists' best-laid plans were thwarted
Through these trackers, the researchers wanted to understand the social dynamics of these birds that usually live in social groups. The researchers wanted to know whether age or sex played a role in the group's interactions or not and just how far do the birds travel on a daily basis.
However, within minutes of setting up the trackers, the hopes of getting desired data began to thin as an older bird that had not been fitted with a tracker came to the rescue of a younger bird that had a tracker. This adult female began attacking the tracking device soon after it was installed and by the third day, all trackers that the researchers had installed were now removed.
The research team isn't sure if it was the same bird that managed to remove all the trackers or if other birds helped out too. Nevertheless, the birds showed "rescue behavior" where they have collectively identified a threat and offered as well as accepted help to minimize the possible danger that could stem from the trackers. Although the trackers would not have harmed the birds, they were not consenting participants in the experiments and "opted out" in their own style.
The researchers, however, aren't disappointed. Even though they were barely able to test their new tracking devices, the results of the study threw up some interesting questions. The tracking device had a weak point in its design. Were the birds able to identify the weak point and attack it? Or did they simply attack it until it eventually fell off?
The study also opens up new areas of research such as the problem-solving abilities of these birds as well as the possibility of collaboration while doing so. It also asks other researchers to factor in the cognitive skills of the animals they wish to study when embarking on such quests.
All in all, a typical day in science.
The study was published in Australian Field Ornithology.
Study abstract: Recent advances in tracking technology have enabled devices such as Global Positioning Systems (GPS) loggers to be used on a wide variety of birds. Although there are established ethical considerations to these processes, different species may react differently to particular devices and attachments. Thus, pilot studies are still of utmost importance in this field. Here, we describe one such study trialling a novel harness design for GPS tracking devices on Australian Magpies Gymnorhina tibicen. Despite previous testing demonstrating the strength and durability of the harness, devices were removed within minutes to hours of initial fitting. Notably, removal was observed to involve one bird snapping another bird’s harness at the only weak point, such that the tracker was released. This behaviour demonstrates both cooperation and a moderate level of problem solving, providing potential further evidence of the cognitive abilities of this species. To our knowledge, this is the first study to report the conspecific removal of GPS trackers, and should be considered when planning future tracking studies especially on highly social species.