SIOUX FALLS, S.D. - The Baird's sparrow, a small songbird that spends its summers in a mostly Canadian swath that dips into grassland prairies in North Dakota, Montana and far northern South Dakota, could be opting for sole Canadian residency in the coming decades.
Climate change and a continuing conversion of grassland into corn and soybean fields will likely push the species' breeding grounds further north of the border by 2025, according to research from the U.S. Geological Survey's Earth Resources Observation and Science (EROS) Center in South Dakota.
Though the research submitted for journal review looked at 50 bird species, the displacement of the Baird's sparrow stands out. That could affect tourism in North Dakota, which draws in avid bird watchers looking to check the Baird's sparrow off their must-see lists.
The bird prefers short grassland, but its summer breeding spots can change with variations in precipitation, said Terry Sohl, a research physical scientist at the centre who is leading the effort.
"They're a little bit nomadic ... and it tends to be tied to moisture. They don't like it too dry, they don't like it too moist," Sohl said.
Sohl's research predicts future land-use trends using the National Land Cover Database, an archive of Landsat satellite images for the entire planet dating back to 1972. Climate change is leading to a warmer, drier northern Great Plains, he said, and that combined with the continued loss of grassland to cropland is pushing the bird's summer breeding range further into Canada.
Julie Zickefoose, who has led tours for about a dozen years to spot the bird during Carrington, North Dakota's annual Potholes & Prairie Festival, said the changes already are noticeable.
"They are getting harder to find," she said. "And it's not absolutely given that they'll be there where they were the year before."
The Baird's sparrow stands about five inches tall with a rather dull palette of brown, white and black, she said.
"As a bird to look at, it's not exciting. It's a tiny, pale, drab sparrow," said Zickefoose, an Ohio-based artist and author. "But it's a very limited range species and so it is a quest bird for a lot of birdwatchers."
Neil Shook, who manages the Chase Lake National Wildlife Refuge for the U.S. Fish and Wildlife Service, said the Baird's sparrow is a tourism draw for North Dakota.
"We get birders from all over the country that come out here, usually specifically to locate a Baird's sparrow," Shook said.
The species prefers cool-season native grasses such as green needle, porcupine and some wheat grasses, and the refuge near Tappen, North Dakota, boasts block of solid grass for about 10,000 acres, he said.
"The amount of grass that we're losing is definitely going to have a negative effect on those birds," he said.
The birds are often heard before they're spotted, with Zickefoose describing their call as unique, "like three introductory notes and then a very soft beat-y trill that rises in inflection."
Arrival at the breeding grounds ranges from late April to early May, and fall migration back to southeastern Arizona, southwestern New Mexico, far western Texas, and north-central Mexico begins in September, according to the Audubon Society.
Shook hasn't yet seen or heard a Baird's sparrow at the refuge this spring.
"If they're not here now, they're going to be here very soon," he said.
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