LAKE ONALASKA BIRDS IN MAY
From the end of April to mid-May in 2021, I watched birds on Lake Onalaska, off the Mississippi River in Wisconsin, through a live camera mounted at the lake and our home computer screen. I saw many of the handsome puddle ducks that were still on the lake since March. Most of these ducks, however, will soon push farther north and west to their nesting territories. And I saw several each of majestic American white pelicans, elegant sandhill cranes, swift tree swallows and immature ring-billed gulls still lingering at Onalaska since earlier spring. These birds, too, will migrate farther north and west, except the ring-bills, and some of the swift-flying and graceful tree swallows that will hatch young in tree cavities around Lake Onalaska.
Around the end of April, flocks of common shorebirds (sandpipers and plovers) began to arrive on the mud flats and shallows at Onalaska. Groups of pectoral sandpipers were about the first species to stop off at Onalaska to feed on invertebrates from the flats and shallows before pushing north to the Arctic tundra to raise young. But soon, least and semi-palmated sandpipers, dunlin, and greater and lesser yellowlegs put down on those same flats and shallows to feed on invertebrates before going farther north to hatch offspring, the first four kinds on the Arctic tundra and the yellowlegs along lakes in Canada's forests.
The first four kinds of sandpipers have brown and darker-streaked feathering that blends them into their mud niche where they pull invertebrates from the mud. But the yellowlegs species are finely-checkered gray and white, which camouflages them over the water they feed in.
Various kinds of sandpipers, feeding in different niches, reduces competition for food with their relatives. And, interestingly, each type is built for its niche. Most sandpipers that feed on mud flats, for example, have short legs. But yellowlegs, and other kinds that feed mostly in water, have longer legs to cope with water depths.
Other, less common, species of shorebirds, including a few each of willets, avocets, Wilson's snipe, golden plovers, short-billed dowitchers and Hudsonian godwits also ingested invertebrates from mud flats and shallows of Lake Onalaska. Plovers have short beaks and get most of their food from the surfaces of the flats. But the sandpipers in this paragraph have long bills they probe into mud under water to pull out invertebrates. All these species, except the avocets, are brown and darker-streaked, which camouflages them in their shoreline habitats.
Avocets have long, thin beaks they sweep back and forth over the water's surface to snare tiny invertebrates. Snipe and dowitchers have lengthy bills they rapidly poke up and down in mud under water to secure invertebrates. All these shorebirds, too, continue their migrations north and west to rear chicks.
Other migrants I saw at Lake Onalaska through the live camera and our computer screen included flocks of Bonaparte's gulls and individual Caspian terns. The small, black-headed gulls were buoyant and dainty on the wing as they caught flying insects from the air and tiny fish from the water's surface.
Terns, on the other hand, pump along on swift, powerful wings until they spot fish near the surface. Then the terns hover for a second or two and drop to the water bill-first. They hit the water with a splash and catch the fish in their beaks. They emerge from the water, shake it out of their feathers and fly off with their prizes.
There also are nesting birds on the islands and mud flats of Lake Onalaska, including several pairs of stately Canada geese that had cute goslings on the flats by early May. The majestic bald eagles and handsome red-winged blackbirds also hatch young on those islands, the eagles in tall trees and the red-wings among tall grasses and other plants on the flats of those islands.
Lake Onalaska, a backwater off the Mississippi River in Wisconsin, is one of the best wildlife refuges throughout the year in the Lower 48 United States. And the live camera there illustrates many of the creatures that frequent that refuge. I've had fun watching wildlife on line from there and I recommend those folks who won't get there to do the same via the live camera and a computer screen.
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