Tracking birds in flight over the Philadelphia skies
Each spring and fall, birds take wing on journeys of thousands of miles, seeking prime breeding habitats or safe and comfortable places to ride out the winter.
Since at least the 16th century, humans have used devices to try to learn more about these lengthy, mysterious travels, first using bands—metal tags wrapped around a bird’s leg—and much more recently, geolocators affixed to the birds’ backs. But for bands and geolocators to be informative, researchers typically need to recapture the same bird to either note the band identification code or to download location information.
A new wildlife tracking technology that emerged in 2014, the Motus Wildlife Tracking System, has the power to fill in the gaps about where, when, how, and why birds migrate, without needing to recapture individual birds. A program of Bird Studies Canada in partnership with collaborating researchers and organizations, Motus consists of an array of antennae installed at a variety of locations, enabling researchers to remotely track birds equipped with ultralight nanotags. The tags “ping” the towers when a bird flies within approximately 15 kilometers (around 9 miles) of an antenna, generating a record that can be accessed by anyone on the Motus website.
Starting this spring, one of those monitoring stations will be in operation on Penn’s campus.
“Urban bird migration isn’t very well understood,” says Brad Gibson, a student in the Master of Environmental Studies (MES) program who helped craft a successful Green Fund proposal that will fund the installation of a Motus station on the roof of David Rittenhouse Labs. “Most of the Motus stations are in more rural areas, so by having one in Philadelphia, we’re helping fill in a gap in our detection system.”
Gibson became interested in Motus after taking a course with Lisa Kiziuk, an instructor in the MES program and director of bird conservation at Willistown Conservation Trust. Kiziuk, along with Dave Brinker of Project Owlnet and Scott Weidensaul of the Ned Smith Center for Nature and Art, manage the Northeast Motus Collaboration, an effort that has led to a network of 18 Motus stations being installed across Pennsylvania.
“In the last 100 years, bird banding has yielded 64 million data points,” Kiziuk says. “Motus, in just the last three years, has generated about 350 million datapoints. We’re learning more about what birds are doing at a finer scale and in far less time than with historical methods, helping to make faster conservation decisions.”
The data coming in can inform conservation priorities, possibly revealing previously unknown critical habitats for endangered species, or indicating that urban light sources interfere with migration patterns. There’s an urgent need for this information, as a third of bird species are in serious decline and at risk of extinction, says Kiziuk.
“The old methods are just too slow,” she says.
Alison Fetterman, an MES alumna and bird conservation associate at Willistown Conservation Trust, played an instrumental role in getting 18 Motus stations placed across Pennsylvania this past summer, the first regional network of sites in the U.S. The data from each of the more than 350 monitoring stations globally is collected by Bird Studies Canada, and it is all openly accessible: a robust resource that could be of interest to Penn students pursuing capstone research projects.
With luck, the Penn monitoring station will be in place in time to capture data on spring migration.
“You can take a single dataset and ask probably 100,000 questions,” Fetterman says. “The possibilities are limitless.”