Editor’s Note: Joe Genzel is Duck Unlimited’s communications coordinator for the Great Lakes/Atlantic Region.

Atlantic Flyway black duck and mallard populations have been declining for decades. In 2019, the mallard limit dropped from four to two birds per day in the flyway, leaving hunters frustrated and confused. Although the four-bird limit was restored last fall, populations haven’t fully rebounded, and East Coast hunters are still wondering what’s going on with mallard and black duck numbers.

To get more answers, biologists have turned to solar-powered GPS telemetry units that hen black ducks and mallards wear like tiny backpacks as the technology tracks their locations hourly using cell-tower signals. The transmitters can also help identify which females are incubating nests. This spring, a new study that builds on these telemetry projects will use drones affixed with infrared cameras to monitor Atlantic Flyway black duck and mallard broods.

After the hatch, several pilots across eastern North America will deploy the camera-equipped drones, conducting at least three counts during the brood-rearing period. The data from the drone study will help waterfowl professionals understand why some broods are successful and others are not, with an eye toward optimizing brood survival.

How Telemetry and Infrared Can Help Duck Studies

Ducks Unlimited is partnering with two universities and several state and federal agencies to fund the project. “From monitoring a subsample of known brood-rearing hens, we will be able to use location and accelerometer data to develop a reliable brood-rearing classification signature and apply that to our entire sample of marked hens,” said Abbey Butler, a graduate student at SUNY-Brockport. “This is a critical first step in determining environmental, habitat, and landscape variables that best explain mallard and black duck reproduction.”

From the 1950s to the 1980s, black duck numbers dropped by 50 percent, pushing the species toward critical levels. The breeding population of black ducks is now stable, but their numbers fall short of North American Waterfowl Management Plan goals. Meanwhile, northeast U.S. breeding mallard numbers have declined 39 percent since 1998, and the Atlantic Flyway population of mallards has dropped 1.1 percent yearly over the same period.

Waterfowl biologists and scientists hypothesize that the decline in eastern black duck and mallard populations may be due to hybridization and the loss and degradation of waterfowl habitat, which affects critical breeding, staging, and wintering areas. GPS location and accelerometer data, along with infrared drone footage of the broods, will ultimately help identify where wetland habitat is most needed by prioritizing critical brood-rearing areas throughout the breeding range of Atlantic Flyway black ducks and mallards.

Although breeding numbers have stabilized, black ducks are still below their long-term population goals.
Although their breeding numbers have stabilized, black ducks are still below their long-term population goals. Ryan Chelius

“Our project will create a framework to close this gap so we can understand why mallard and black duck broods are successful or fail,” said Jake Straub, a senior research associate at SUNY-Brockport.

Last spring, the NYSDEC aviation unit and a private operator in Ontario partnered on a pilot program, attempting to locate and monitor GPS-tagged hen mallards suspected of hatching broods. Drone pilots made 13 flights and confirmed broods on over half the flights.

“Even with GPS-marked hens, it was a challenge to ensure we documented transmitted hens and their broods, as many wetlands had multiple mallard broods,” said Josh Stiller, NYSDEC’s Small Game Unit Leader. “We will take what we learned during the pilot year and dial in our approach.”

Ducks Unlimited partners for this project include SUNY-Brockport, the New York State Department of Environmental Conservation (NYSDEC), the Pennsylvania Game Commission, the University of Saskatchewan, and several other state, provincial, and federal agencies. The goal is to get one step closer to identifying why the eastern mallard and black duck populations continue to decline, hopefully leading to more birds in the sky each fall.