Researchers testing a hypothesis believe they have 50 years of data showing the link between climate change and a northward shift of 16 species of dabblers and divers that traditionally overwinter in the southern regions of the Atlantic and Mississippi flyways. Their conclusion—published in the Journal of Wildlife Management—is not good news for Southern duck hunters.
The study, by researchers from the National Audubon Society and Clemson University’s James C. Kennedy Waterfowl and Wetlands Conservation Center, is based on data collected during Audubon’s annual Christmas Bird Count (CBC) from 1969 to 2019. The CBC results from both amateur birders and scientists reporting on local bird populations each December and January.
“We’ve suspected that warming temperatures are changing the types of waterfowl that we’re seeing in different regions,” said Dr. Tim Meehan, quantitative ecologist at the National Audubon Society and the lead author of the study, “and these data confirm that. The weather has stopped becoming severe enough in the winter to prompt the birds to fly south. They’re staying farther north, and they’re telling us that something fundamental has changed in their environment.”
The data from the annual citizen-science bird counts show that while there wasn’t a major change in populations overall, there were noticeable changes in abundances in locations that corresponded with warming temperatures. For example, the black duck (pictured here) showed a stable population overall but a marked increase in presence in traditionally colder northern locations and a reduction in traditionally warmer regions.
The implications are far-reaching up and down both major flyways. Waterfowl conservation and management plans will have to be adapted to this new reality, and both duck hunting and the local economies that rely upon it may suffer. As well, waterfowl populations that have long relied on reaching the rich farmland farther south may not be sustained in the same numbers by wintering farther north.
To read the study, google “half-century winter duck abundance and temperature trends.”