By plotting the locations of satellite-marked birds throughout the year, researchers gained a better understanding of the movements and habitat preferences of mallards at both continental and regional levels. PHOTO: Gang Wang, DU
While fall migration is of greatest interest to hunters, waterfowl habitat conditions during spring migration may be more important to duck populations. The observation of satellite-marked birds during our study revealed that mallard migration strategies are more flexible in spring than in fall. The average length of spring migration varied by year, ranging from 18 days to 48 days, with an average stopover time of about 12 days while en route. More than 75 percent of satellite-marked mallards from Arkansas either nested in the Prairie Pothole Region or migrated through the region en route to their eventual nesting destination.
This research has helped to fill in missing pieces of the puzzle of mallard movements and how the birds use habitat, including newly restored habitats. Since 1990, the NRCS has worked with over 11,000 private landowners to protect more than 2.6 million acres of wildlife habitat through the Wetlands Reserve Program (WRP)
. The precision of GPS satellite telemetry units has enabled University of Missouri researchers to confirm that mallards use WRP wetlands frequently during migration and winter. Researchers have also documented that areas with large wetland complexes—especially those along the Mississippi and Missouri river corridors—are used more frequently than are more isolated wetlands. On a daily basis, local movements of satellite-marked mallards averaged only about two miles, and most were less than eight miles. For hunters, this would suggest that complexes of quality habitat will offer better hunting than fragmented habitat. For waterfowl managers, it suggests that restoring wetlands in close proximity to one another will likely be of greater benefit to waterfowl than spreading out wetlands across the landscape.
An unexpected benefit of this partnership was that it enabled waterfowl hunters to access the same information available to waterfowl biologists. The AGFC partnered with the Center for Advanced Spatial Technologies at the University of Arkansas to develop a website displaying locations of marked birds. While no longer online, this website provided a unique opportunity for the public to track the mallard migration as it unfolded across this continent. Tracking individual birds offers a fascinating look at the variation in duck behavior and the birds' habitat preferences. As hunters and scientists watched the movements of mallards across the landscape in nearly real time, together they could begin answering questions about duck movements and habitat selection that could improve hunting prospects and bolster future conservation efforts.
Luke Naylor is waterfowl program coordinator for the Arkansas Game and Fish Commission. Dr. Andrew Raedeke is a resource scientist with the Missouri Department of Conservation.
Mallard Tracking Facts
- The average distance traveled by satellite-marked mallards during spring migration was more than 730 miles. The average distance traveled by individual birds during fall migration was almost 875 miles.
- One of the first mallards (a drake) ever marked with a GPS satellite transmitter in Arkansas flew more than 500 miles during spring migration, from Minnesota to Saskatchewan, in only four days.
- This same bird made a remarkable one-day flight in early fall from Saskatchewan to south-central Iowa—a distance of more than 900 miles!
- Although fall migration commonly is thought of as a one-way trip, several mallards in the tracking study made south-to-north movements during fall and winter.