In California’s San Francisco Bay Delta watershed, conservationists have been working for decades to coax farmers into adopting wildlife-friendly farming practices to help migratory birds like the magnificent sandhill crane. Their efforts seem to be working, but counting the number of birds migrating through the Bay Delta has been a laborious and painstaking process—until the drones appeared.
The Nature Conservancy is testing out an unmanned aerial vehicle topped with an infrared camera to get a more accurate, quicker count of the birds. Each morning, the birds take to the sky together from shallow water. “It’s an amazing sound and scene—they put out this very primeval call, and then they all get up and fly out to go foraging for the day,” says Rodd Kelsey, the Nature Conservancy’s lead scientist for the Central Valley & Mountains region. “Drones enable us to [count them] faster, cheaper, and more accurately.”
This spring, the team tested a fixed-wing drone with an infrared camera. The birds show up as dark spots on the water because their feathers retain body heat. Getting an accurate count is as simple as tallying the dark dots, says Kelsey. The drone is battery powered, so it’s quiet enough to hover over the birds without disturbing them.
The next tests, which will happen in the fall, will involve taking pictures of a wider swatch of land and stitching together the images. This bird-counting application joins a growing number of projects using drones for conservation, from bat monitoring to antipoaching efforts.
“One thing we’re exploring with academic partners is to measure water temperature in rivers,” says Kelsey. “You could fly along an entire river and collect temp of water, which is important to know for efforts to preserve salmon and trout habitats.”
Despite the influx of hi-tech methodology, Kelsey says the core conservation mission hasn’t changed: “The technology is developing fast. I don’t think we even know how far this can be taken yet.”