Radio-tagging and Monitoring
A High-Tech Game of Tag
The Bioacoustics Research Program (BRP) helps researchers listen in on the world’s creatures, track their movements, and decipher what animal sounds and behaviors mean. A group of creative BRP design engineers develops the cutting-edge radio frequency (RF) hardware needed to make this possible for studies on everything from Arctic whales to African elephants.
“We’re on the brink of an animal tracking revolution,” says BRP design engineer Rob MacCurdy. “We’re doing things that people have not chosen to do and we’re doing them on a scale that’s appropriate for biologists and for small organizations.” The technology is an integral part of scientific studies taking place at the Cornell Lab of Ornithology. Lab scientist Dr. Alejandro Purgue is the principal investigator on all the radio frequency projects. “My first interest is science," he says. "I do engineering not as an end in itself but because the biological questions I want to answer cannot be answered with existing technology.”
Gizmos and Gadgets
Among the devices already designed, tested, and put into service by the design group are the workhorses of the Bioacoustics Research Program: underwater recorders called pop-ups and their land-based cousins, the autonomous recording units (ARUs).
Building Better Mousetraps
The RF design group is now hard at work on two exciting grant-funded projects, both of which address specific problems in remote and long-distance animal monitoring.
Moore Foundation Project
National Science Foundation Mini-Tagging Project
Another challenge for scientists is tracking small animals over long distances, especially birds. A National Science Foundation grant is funding the development of lighter, smarter tags that smaller birds and animals can carry.
The tags being used now do not do much more than transmit. Lab scientist Alejandro Purgue says, “Our mini-tags have a built-in computer that can be programmed to gather data at specific times. They can also store information and share data with tags on nearby animals.” Currently, tags transmit on a pre-set schedule regardless of whether anyone is listening. The mini-tags are silent and only transmit when they are being queried by a transmitter in range—so there are no idle transmissions. “This saves a lot of power,” Purgue says, “It extends life of the unit, and allows the use of a smaller battery.”
A prototype system was ready at the end of 2006. Dr. Purgue will be there when it is deployed by the Netherlands Institute of Oceanographic Research (NIOZ) to study Red Knots flying from Africa, over Germany, on to Siberia. It’s likely some version of this technology will be used for his primary area of interest, whale tagging. In this case, the stored position data would be uploaded to a tag on a passing bird perhaps, and downloaded by a scientist on shore when the bird comes within range—rather like a cell phone call skipping from cell to cell to get to its final destination. Whales stay too far from shore to make a direct tag query feasible—at least for now.
The Greater Good
In the past researchers have only been able to track one animal at a time and collect sporadic information about where it went. The work being done by the RF group will help advance understanding about how much land animals actually need, what areas of the earth they are using, and what impact humans may have when they disturb habitats. Armed with that data, leaders can make informed decisions about how land will be managed. “There are lots of places where you can do interesting engineering work,” says Rob MacCurdy, “But very few places where you can do interesting engineering work and have a real impact on animal conservation.”