Last Halloween, an interesting study of blood-sucking bats showed that the scary-looking animal also formed close friendships, sharing food with hungry companions, combing each other’s hair, and so on. A paper published April 2 in the Public Library of Science: Biology details the role behind the social study of bats: a mini “backpack” used to monitor small animals.
These small backpacks, which are glued to bats, were developed by a team of computer scientists, biologists and engineers and include smartphone features such as motion monitoring and Bluetooth connectivity. They can communicate with each other, as well as with ground stations.
According to the introduction, “backpack” can be highly complementary to GPS positioning. GPS can track animals on a larger scale, but once bats get into holes or hollow trees, satellite signals are interrupted. However, “home” is often the place where social behavior is most intense.
Adult blood-sucking bats generally weigh between 28 and 42 grams and are less than 10 cm long. Clearly, the automation and lightweighting of “backpacks” is essential. Strap-type, neck-ring-type devices traditionally used to track larger wildlife are not suitable.
Simon Ripperger, a researcher in evolutionary, ecological and tissue biology at Ohio State University, remembers that when he was studying for his Ph.D. a decade ago, he used a very primitive wire-free telemetry technology that sometimes required a hand-held antenna to run after the animal. Even so, he can only calculate the animal’s position every 2 minutes at most within 30 meters.
Later, The joint team involved in Lipger spent about seven years manufacturing equipment from scratch, trying to weave the highest-performance networks with ultra-low energy consumption levels.
The battery capacity for the “backpack” is only 5% of the capacity of the No. 7 battery. Lipger introduced, an energy-saving trick is wake-up sensor, usually in energy-saving mode, only received a signal from another bat will wake up, two seconds apart frequency broadcast a signal, as if shouting “I’m here!” I am here! “
The entire micro-computer network is encapsulated in 3D-printed plastic bags that are lighter than a penny.
Lipger believes that the benefit of the “backpack” is not only to lose weight, but also to be ground in the bat’s habitat after an average of two weeks. In this way, bats do not have to bear the extra load for long periods of time. These shedding devices can be recycled and recharged by researchers.
During the two-week test, 50 blood-sucking bats were tagged with backpacks, generating data equivalent to about 400,000 meetings.
In addition to bats, the Backpack tracker is also suitable for small birds, rodents, reptiles and amphibians. After “sneaking” the pulse between bats, Lipger believes that marking blood-sucking bats and cattle in this way could help scientists better understand the spread of rabies.
He is currently working with colleagues to attach a “backpack” to the protected animal lizards near the German railway line to investigate how track maintenance affects their lives.