ASHLAND, WI - Wisconsin birders are again being treated to a significant showing of snowy owls from Canada’s arctic tundra while resident American goldfinches are dominating backyard feeders in most areas, state bird experts say.
“We’re seeing a significant number of snowy owls this fall and early winter – well above average. So far the flight is not as big here as two years ago, but we are on the western edge of a massive and possibly historic irruption from the Great Lakes east to the Atlantic coast, an event that’s making national headlines,” said Ryan Brady, a Wisconsin Department of Natural Resources research scientist who coordinates bird monitoring for the Wisconsin Bird Conservation Initiative.
Hundreds of the owls have been seen at many locations across the eastern U.S. as far south as North Carolina and even to the islands of Bermuda, over 600 miles out in the Atlantic Ocean. Observers in Newfoundland tallied more than 200 owls along a single 25-mile stretch of road, Brady said. Read more about the irruption and see maps and other resources in Brady’s Dec. 9 article on Wisconsin eBird.
In Wisconsin, about 55 snowy owls have been reported in Wisconsin through Dec. 8 via eBird, listserves, Facebook groups, WI-DNR staff, and other sources - and surely many more are present and either haven’t been reported or seen, Brady said. This compares to about 115 owls by the same date during the large irruption of 2011-12, 30-35 owls in 2012-13, and zero in 2010-11.
Brady said Wisconsin’s snowy owl sightings got off to relatively slow start, with only five individual birds reported before Thanksgiving. By early December, however, reports picked up rapidly, including on the first of the month five birds found in Ashland and an amazing 11 birds at lower Green Bay, as well as inland birds at Goose Pond, Horicon Marsh, Marathon County, and other locations, he said.
Bird experts aren’t sure what’s behind this year’s irruption. Snowy owl movements are usually tied to lemming populations, a favorite prey whose numbers vary in Canada each year. One possibility is a very robust supply of lemmings, which allows the owls to raise many young. These young snowy owls then must disperse south to find their own territory and food, Brady said.
A second possibility is the opposite – lemming populations are low so, owl reproduction was relatively poor and all birds young and old must fly south to find food.
While the 2011-12 irruption was believed to be due to a strong lemming population leading to more young birds dispersing southward, experts aren’t sure yet about the reason for this year’s exceptional influx.
Brady said birders can maximize their chances of finding a snowy owl by checking suitable habitats such as coastal beaches, harbors , and breakwalls, open grasslands and agricultural fields (e.g. Buena Vista Wildlife Area), large wetland complexes like Horicon Marsh, airports, and vast expanses of ice, which provide excellent tundra-like roosting habitat.
Snowy owls aren’t the only feathered friends putting on a show this December. Brady said American goldfinches are also gracing the state in above average numbers, especially across the Northwoods and along Lake Michigan.
The birds are especially welcome given the scarcity of other irruptive winter finches this year, Brady said.
“Last winter Wisconsinites were treated to a spectacular flight of redpolls, siskins, crossbills and grosbeaks," he said. "In contrast, all of these species are nearly absent from Wisconsin this year so far.”
Ample cone crops and fruit sources across the boreal forest are likely holding them there, according to Brady.
The good news is, these goldfinches will likely stay for the winter and often set up shop at bird feeders, providing great viewing opportunities, if not their namesake color.
Like many birds, goldfinches molt in the late summer and fall, losing their golden feathers for a more wintery brown. By late winter and spring, patches of yellow feathers appear successively until the bird again dons its splendid breeding plumage.
Brady said bird lovers can keep their goldfinches and other backyard birds happy by providing foods such as sunflower and thistle seeds, a heated birdbath, and shelter in the form of thick shrubs, brush piles, and trees. Feeders and spent seed should be cleaned regularly to avoid spread of disease.
For more information, contact Brady at 715-685-2933.
SOURCE: Wisconsin DNR