FALL MUDFLAT GATHERINGS

      Every year, after the spring migration and raising young in summer, by August through September, flocks of several kinds of water-loving, post-breeding birds rest and feed on the mudflats and in shallows of Lake Onalaska, a backwater off the Mississippi River in Wisconsin.  Those flats and shallows often are nearly covered with busy water birds that I am excited to see through a live camera and our computer screen as they go about their business of recovering from rearing offspring, and preparing for winter.

     Flocks of stately American white pelicans, double-crested cormorants, ring-billed gulls and caspian terns rest on the flats and catch fish in the shallows, each species in its unique way, which is intriguing to see.  Groups of pelicans work together on the water's surface to herd small fish against a flat where the pelicans all repeatedly dip their large, pouched beaks into the water to scoop up fish.  Individual cormorants dive under water from the surface to snare fish, one at a time, in their hooked bills.  Solitary caspian terns hover in the air over the water, and drop into it to grab fish, when that finny prey is spotted from aloft.

     Flights of the huge American white pelicans are magnificent to see.  Usually they fly in long, undulating lines, each bird alternately beating its wings and sailing, as each line moves rapidly along.

     Several majestic bald eagles, both adults and immatures, perch on the flats and in trees to rest and scan the lake for prey.  Bald eagles flap and soar elegantly over large bodies of fresh water to watch for large fish near the water's surface.  When prey is spotted, each eagle quickly stoops toward it and reaches down with eight curved, sharp talons on two feet to grab the fish on the surface without the eagle's body hitting the water.  It's always exciting to see eagles dropping to water after large fish.  And these eagles don't compete with other fish catchers that snare small fish.  

     Gatherings of sandhill cranes stalk about on Onalaska's flats and shallows where they feast on invertebrates, small fish, seeds and other edibles.  Tall, majestic birds, they look somewhat like herons and egrets with their long legs, necks and beaks. 

     Individual great egrets and great blue herons stealthily wade on long legs through the shallows after fish of various sizes.  When a fish is spotted, each tall bird quickly shoots out its lengthy neck and beak to snare the prey, but, sometimes, they are not fast enough. 

     Little groups of sandpipers, including least, semi-palmated and pectoral sandpipers, dunlin and lesser yellowlegs, down from the Arctic, gather on the flats and shallows to eat invertebrates, which builds up their fat reserves and stamina for the next part of their migrations south to escape the northern winter.  All those sandpipers, except the yellowlegs, are mostly brown because they feed on mud flats.  Brown feathers, which evolved on a brown habitat, camouflage these small, feathered travelers.  Yellowlegs have gray feathers mostly, which blend them into the color of the shallows, where they get food. 

     Flocks of noisy Canada geese and a small variety of puddle ducks, sometimes dominate the flats and shallows in fall.  Most of the ducks have brown plumages, as the males lost their colorful, spring feathers early in summer.  The ducks resting, and feeding on greens and seeds at Onalaska in September, are mostly mallards, northern pintails, American wigeons, green-winged teal, wood ducks and blue-winged teal.  Males of each kind get new breeding plumages during September, into October.  

     There is a random collection of post-breeding birds at Onalaska in August and September.  Many tree swallows are noted swooping over the lake to catch and consume flying insects.  Strikingly feathered red-winged blackbirds perch on tall grasses and wild rice, from which they eat seeds.  Occasionally, I see a beautiful northern harrier pumping slowly into the wind, while watching for rodents among the vegetation of some of the flats.  And I saw a couple each of yellow rails and sora rails feeding on invertebrates and seeds on the flats, near a tall shelter of grasses, rice and beautifully-flowering purple loosestrife.      

     The mud flats and shallows of Onalaska in August and September are often covered with intriguing, post-breeding birds of various species, which can be experienced by a live camera.  The birds have a safe place to rest from raising young and eat to build strength and fat to continue their migrations south to avoid the northern winter.  And Lake Onalaska is one of many places in the Lower 48 where migrant birds can find refuge.