Green Scene

Sandra Lines/For the Herald

Green heads gather in the marsh to discuss dinner plans.

Glistening fall colors along Clinton’s riverfront signal the seasonal migration of waterbirds on the Mississippi River. The great white pelicans have moved their fish trawling operations south. Thousands of ducks, geese and swans have taken their place, performing synchronized aerial acrobatics as they migrate into our area. Magnificent bald eagles are sitting vigilantly along the shoreline, searching for their next winged cuisine.

Some waterbirds are here only for a refueling stop; they dine at the snack bar containing high protein seeds that are produced in the marsh. Others book a longer stay and feast at the all-you-can-eat buffet of fish, snails, mussels and tubers. As winter approaches and ice hardens the river, the last stragglers will head south to warmer climates. Slow moving or injured birds become dinner for the many predators that patrol the marshes.

State and federal wildlife management areas form a chain of pearls along the river that provide habitat and sanctuary for the waterbird migration. The Upper Mississippi River National Wildlife and Fish Refuge extends 261 miles and borders Clinton to the north and south. Wetland management programs include growing native moist soil plants by dewatering marsh areas during the growing season and flooding them during the migration period.

Large numbers of waterfowl and coots attract attention, especially by bald eagles. During winter, there are typically 1,000 bald eagles present within a 50-mile radius of Clinton. A favorite bald eagle observation site is Lock and Dam 13 in Fulton, Illinois. The highest concentration of eagles occurs after the river channel freezes. Ice cold water pouring through the dam stuns fish and creates a floating sushi banquet in the tailwaters that is easy pickins for hungry bald eagles.

A live-streaming internet web cam is located at Lock and Dam 13 for bald eagle viewing. The web cam project is a partnership between the Corps of Engineers, U.S. Fish and Wildlife Service and the Stewards of Upper Mississippi River Refuge. The web cam can be viewed on the Stewards website at www.stewardsumrr.org.

A growing population of sandhill cranes are staging in preparation for their migration south. Hundreds of cranes gather in our area to chart their group flight south. These vegetarian and insectivorous feeders make frequent flights from the marshes to inland fields. Groups of cranes noisily chatter during these low level roundtrip flights.

Migrating waterbirds are long-distance travelers. They endure many hazards including ice storms, disease, predation and hunting pressure. Avian influenza is a threat to trans-continental fliers. Trematodiasis is a relatively new threat in our area that causes waterfowl mortality from a parasitic infection. These parasites were initially brought into the United States living within the non-native faucet snail. When eaten by waterbirds, the parasites cause intestinal bleeding that result in death.

The first trematodiasis mortality in waterfowl in our area occurred in October 2012 when hundreds of coots and a few blue-winged teal were found dead in Pool 13 near Fulton. In the La Crosse, Wisconsin, area, thousands of waterfowl typically die annually from trematodiasis. The parasite is expanding its range by infecting native snails, a delicacy of waterfowl.

We are truly fortunate to have an abundance and variety of waterbirds at our back door. It provides a great opportunity to view many species of ducks, geese, swans and cranes. Take the time to get out and enjoy the winged migration before Ole Man Winter re-claims the river to an ice arena.

Ed Britton is a Wildlife Refuge Manager on the Upper Mississippi River National Wildlife and Fish Refuge, and a volunteer at Bickelhaupt Arboretum.

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