By Dr. Drew Fowler, Waterfowl and Migratory Game Bird Research Scientist, Wisconsin Department of Natural Resources
This article originally appeared in Wisconsin Waterfowl Association’s September Newsletter edition.
Was it just me or did summer fly by faster than normal? It’s a busy time of the year: kids are back in school, football is in season, and ducks and geese are back in the air. I’m in the air as I write this, via airplane, though. I’m returning from the 8th North American Duck Symposium, this time hosted in Winnipeg, Manitoba. This conference gathers wetland conservation practitioners, state waterfowl biologists, and research scientists from across the country to share current research and perspectives that are all about duck conservation and management. I wish every duck hunter in Wisconsin could attend. The emerging research, new talent, and camaraderie can’t be beat.
I was super excited to bring new research we’re starting at Wisconsin DNR to share at the Duck Symposium. As you all know, assessing annual duck production is paramount to estimating the fall flight, in addition to establishing relationships between habitat and duck abundance. Traditionally, assessing duck productivity has been conducted by dedicated biologists counting duck broods from the edge of wetlands. This practice has a long history, but detecting all broods with complete accuracy is challenging and can often result in underestimates with unknown magnitude.
This year, the Wisconsin DNR Waterfowl Research Program began testing new technology that could assist in improving waterfowl brood counts and access to remote wetlands that are notoriously difficult to survey. Just this past May we partnered with the University of Wisconsin – Stevens Point and began flying an unmanned aerial vehicle (AKA, a pretty slick drone) in northern Wisconsin to test its capability to find duckling broods as well as actual nests. Our drone carries both a high-resolution visual camera and a thermal sensor. It’s this thermal sensor that gives the drone its searching power. There’s lots of technology behind how these thermal sensors work, but in short, it provides the opportunity to identify heat signatures that enhance detection when objects may be obscured or hidden in a traditional visible light spectrum.
Because ducks emit body heat it’s possible to use a thermal sensor to pick out hens and broods that are scattered among wetland plants that couldn’t be seen or observed from alongside a road. Similarly, the thermal sensor can pick out cryptic hens while incubating their nests, and the sensor can even distinguish residual heat from individual eggs. This summer we worked with the drone over floating bog sedge wetlands in Vilas county while conducting a pilot research season to understand habitat associations of nesting ring-necked ducks.
Nonetheless, the drone and its sensors have limitations in their detection capabilities, and we’ve got lots more testing we want to do. For instance, high humidity can cause “noise” in the thermal sensor and create false positives that look like nests or ducklings from a distance, but actually aren’t. Still, we think there’s lots of opportunities for this new type of remote sensing tool to help address a variety of waterfowl and wetland related research questions.
There’s lots more really interesting waterfowl research our Waterfowl Research Program is beginning to initiate with sharp collaborators throughout the state. As those develop, we’ll be sure to keep you in the loop. In the meantime, get outside and get ready for the fall flight!