Biologists at the University of St. Andrews (Scotland) have been inspired by the concept of Twitter, the microblogging service used to post short text messages known as tweets, toobserve what happens when birds come into contact with each other while in the wild.
Specifically, the researchers studied the behavior ofNew Caledonian crows, an archipelago of islands located in the South Pacific. Crows are known primarily for their ability to use different tools to extract prey from within dead wood and vegetation. Still, biologists wondered how much, if anything, birds could learn by observing each other. To find out, they used an electronic tag designed by the University of Washington (USA).
Biologists typically tag animals with radio transmitters, which then transmit at a certain frequency. The researchers in the field then use a receiver to listen to that frequency and detect when the animal is present. This has the disadvantage that any encounter between small animals is only recorded if the researcher is in the vicinity. However, the new system, calledEncounternet, uses programmable digital tags that can send and receive pulses. “Encounternet tags can monitor each other, so it is possible to study interactions between animals,” explained co-author John Burt, associate professor of electrical engineering at UW.
The results, described inCurrent Biology, reveal a surprising number of unrelated contacts between ravens.During a week, the technology recorded more than 28,000 interactions between 34 crows. While New Caledonian crow family units contain only three members, the study found that all of the birds were connected to a larger social network.
The use of UW tags to record social interactions between animals is a first, and this is the first published study to use this technology. “It’s about anew kind of animal tracking technology”Explained Brian Otis, engineer and study co-author. “Ecology is one of many fields that will be transformed by the presence of miniaturized, low-power wireless sensors,” says Otis.
Animal social networks
“Right now the idea that animals have social networks is in vogue,” says Burt. “There are other tags that can record what happens in the vicinity, but they are all very large and suitable for larger animals: none are as small as Encounternet, by far.” The smallest label from the University of Washingtonweighs less than a gramand it can be used in animals as small as 20 grams, the weight of a sparrow.
Now they are working on adding a GPS component that records the location of the encounters, as well as integrating an accelerometer and other sensors that can detect the behavior of the animal. “This development has generated great enthusiasm as, for the first time, it enables the interactions and networks between smaller animals to be studied in extremely fine detail,” explains Burt. “Apparently,social media is the key to understanding many of the behaviors of animals; and we believe that Encounternet is the only medium that exists capable of obtaining that information, “he points out.
