Seasons of Wildlife
March transitions from the silence of winter into a boisterous mix of sights and sounds as the tens of thousands of birds hurry their way north. Canada geese, white-fronted geese and trumpeter swans typically lead the northward flight and are followed shortly thereafter by mallards, northern pintails and a variety of diving ducks. Later arriving waterfowl such as blue-winged teal and gadwall peak in April as a wide array of herons, egrets, ibis, shorebirds, songbirds and raptors such as peregrine falcons join the fray.
By mid-May the migration party is largely over and the district’s role as a breeding ground becomes paramount. Canada goose broods and some mallard broods are already bustling about as blue-winged teal carry on the customary head bobbing of courtship. Colorful bobolinks take to their singing flights having freshly arrived from their winter vacation in Argentina. All the while, choruses of frogs dutifully sing throughout the marshes. By August, the waterfowl production areas fall silent again as courtship has ended and waterfowl carry out a molt that leaves them flightless. Trumpeter swan broods will remain intact into September as the cygnets slowly gain the strength to fly.
For early migrating shorebirds, fall actually begins in late July and peaks in August. They are delighted by the buffet of food produced during the summer and left on the mudflats and in the sheet water following the heat of the summer. Watch as this same shallow water smorgasbord feeds thousands of larger migrating species ranging from mallards and northern pintails to great blue herons and great egrets. As the fall progresses towards winter, ice forms on the marshes. Thousands of mallards, northern pintails and Canada geese use their collective body heat to maintain pockets of open water in the ice. All the while, bald eagles hold watch nearby - hoping for a tasty snack!
Eventually the snow comes and the land returns to the desolate silence of the Iowa winter - broken only by the lonely howls of coyotes in the distance longing for spring’s boisterous return!
The district supports 14 species of breeding waterfowl including blue-winged teal, mallards, wood ducks and trumpeter swans. In all, more than 270 species of birds are known to occur within the district boundary. Thirteen of those bird species are state listed as threatened, endangered or of special concern. The least tern is listed as federally endangered.
There are seven other federally listed species within the district boundary. The Topeka shiner, Poweshiek skipperling, rusty patched bumble bee and Indiana bat are endangered; the northern long-eared bat, western prairie fringed orchid and prairie bush clover are threatened.
The district is home to a variety of resident wildlife including river otters, American badgers, white-tailed deer, wild turkey, ring-necked pheasants and coyotes.