Lack of southern winds slows migration
The recent streak of cooler weather seems to have stalled much of the spring migration through the region, though some new arrivals have appeared in the region.
Blame the wind patterns, which have not been favorable, said Ryan Brady, Natural Heritage Conservation biologist for the Wisconsin Department of Natural Resources office in Ashland.
“Migration has slogged at a snail’s pace here in the north for nearly two weeks now, mostly due to a lack of southerly winds,” Brady posted on his Facebook page Sunday.
Still, some have powered through, most notably the first northern flickers, warbler species such as yellow-rumped, tree swallows and fox and white-throated sparrows. Turkey vultures are back in force.
Elsewhere in the Upper Peninsula, common loons have been photographed in the Big Bay de Noc in Delta County.
Across the border in Florence County, what I thought might be a bald eagle nest had a single osprey Friday busily working to add sticks and clumps of grasses.
This probably was a male, which normally is first to return to the nest site and fetches most of the nesting material, according to the Cornell Lab of Ornithology’s All About Birds web site, www.allaboutbirds.org.
These raptors will migrate considerable distance, as far as South America, so nesting is much later than, say, bald eagles, which will begin incubating eggs in northern Wisconsin in March. An almost exclusively fish diet also means the osprey can’t really get started until enough water has opened up.
While osprey, like bald eagles, form exclusive pairs for nesting, the idea that they “mate for life” is a little misleading, said Laura Erickson of Duluth, Minn., an author who was science editor at the Cornell Lab of Ornithology and now is known for her podcast, blog and long-running public radio program, “For the Birds.”
Sandhill cranes and Canada geese will keep their pair bonds active even after breeding season is done. But osprey and eagles “fall in love” with the nest, not with their partner, Erickson explained. If something happens to split up the pair — a rival intrudes, or one simply doesn’t show up — the remaining bird often is more than willing to take up with whoever is available so long as they can stay at that nest site.
But if the same birds show up at the same nest and can manage to fend off others, they’ll maintain that pairing year after year, for as long as it manages to successfully produce chicks.
While it hasn’t really felt like it so far, the time technically is near when Baltimore orioles, rose-breasted grosbeaks and ruby-throated hummingbirds should begin nudging their way north. Some already have been photographed in Illinois and southern Michigan. So haul out those feeders and have a few oranges on hand, just in case.