Iowa Iowa Becomes Focus For Study On Declining Scaup Population Don't be too surprised if you happen to spot a lime green, fluorescent orange, or bright red duck swimming across your favorite wetland this spring. According to Louisiana State University wildlife research assistant, Mike Szymanski, the kaleidoscope colored ducks are all part of an ongoing study designed to provide answers as to why populations of lesser scaup are on the wane. Known to most duck hunters as bluebills, lesser scaup are an important waterfowl species of the Mississippi Flyway. But while most duck species have shown healthy increases during the past decade, overall scaup numbers have shown an alarming decline. Although no one can say why scaup populations are falling off so rapidly, finding the answers may depend in part on keeping track of color coded bluebills as they travel to Canadian breeding areas. "This study will ultimately involve hundreds of people from Louisiana to Canada," said Szymanski. "Currently, we are [bait] trapping, banding, and color marking as many migrating lesser scaup as we can get our hands on." The capture efforts are focused on the Mississippi River at Keokuk where large numbers of the ducks stage during spring and fall migrations. With this year's spring migration currently reaching its peak, scientists hope to capture and color mark between 3,000 and 5,000 of the northbound ducks. As the birds disperse across Iowa and points beyond, researchers are relying on public sightings to help unravel the mystery of scaup migration. "What we are attempting is to document migration corridors and rates of movements from Keokuk to the breeding grounds in the boreal forest region of western Canada," said Szymanski. "It's possible that during the first half of the spring migration, a majority of scaup may visit the Dakotas. Later in the migration, more birds may travel north across Minnesota. At this point, we don't know the exact routes they travel, and visual sightings will play a key role in providing that information. What we're really looking for is the when and where of scaup migration." What researchers do know is that when northbound scaup arrive at Keokuk, they are in excellent body condition. However, as the migration continues across Iowa many of the birds begin to lose weight. Biologists say the weight loss could result in decreased egg production, reduced survival of adult females, and lower population recruitment. "At this point, no one can say for sure why scaup are losing weight as they travel across Iowa," says Szymanski. "It could be food, it could be parasites, it could be contaminates. Once we have those answers we can begin working on a solution." During the next two summers, biologists plan to sample wetland feeding grounds in Iowa, Minnesota, and North Dakota. Researchers will be looking at the abundance of invertebrate marsh life [the primary protein source for migrating scaup], testing for chemical pollutants, and measuring the level of sedimentation due to agricultural runoff. "There is strong evidence that migrating scaup are missing