I had an interesting visit with Jim Nissen and Kevin Kenow last Friday.

Nissen is the La Crosse District Manager of the National Wildlife Refuge on the Mississippi River. He works for the U.S. Fish and Wildlife Service (USFWS). Kenow is a researcher with the U.S. Geological Society. They are also both experts on tundra swans.

I asked them to meet me and some friends at ìSwan Central USAî last Friday. Thatís what I call the area on Raft Channel West, between Shellhorn and Reno. Jim and Kevin graciously agreed. So we parked next to the Highway 26 Peninsula in front of the old Heiller homestead five miles south of Brownsville. (I keep insisting that Jim should change the name on his maps to Heiller Bay, but he isnít enthusiastic about the idea.)

We didnít see many swans, perhaps 100 or so. A survey done on October 25 this year counted 380 swans on the Wisconsin Island Closed Area, which comprises 6,500 acres from Raft Channel south to Lock and Dam 8 at Genoa, Wisconsin. Thatís just a fraction of the 6,000 swans that Jim, Kevin, and I viewed from this same spot last November. Last year an aerial survey at that time counted 18,000 swans on Pool 8, which runs from the Dresbach to the Genoa dams. So the swans will be arriving soon.

Here are some of the questions that Jim and Kevin answered.

Why are so many swans here in the fall? The refuge area south of Shellhorn is full of swan food, in particular arrowhead tubers, sago pondweed, and wild celery. The Eastern Population of tundra swans, which is what we see, needs to stop somewhere on its trip from the Canadian tundra to the eastern seaboard. The birds need to refuel, because they will lose a lot of weight in their wintering grounds. They stay here for an average time of 33 days, leaving when the river ices up. More than 25 percent of the entire Eastern Population uses the refuge, and about half the cygnets (juvenile) birds use it.

Why so many now? Prior to 1980, there was little swan use in the area, Kenow said. There has been a 700 percent increase is usage since then. Hereís an amazing statistic: in 1997, there was a peak population of 1,000 ducks on the refuge. The next year, 125,000 were counted. The reason is the great food source.

Why is there more food now? Several things came together for that. The USFWS and Army Corp of Engineers did a lot of island building and wetland restoration starting in the early 1990s. That provided better habitat, better loafing areas, and more food sources. More invertebrates and submersed plants arrived. The biggest boon to the food supply came in 2001 and 2002 when there was a ìdrawdownî in Pool 8. The water was lowered, exposing a lot of the mud flats in the river, especially in Heiller Bay (sorry, Jim). Arrowhead plant seeds that had been lying dormant for decades were exposed to sun and air. They shot up and flourished. It seemed like a miracle to me, although it was no surprise to Kevin. Heíd seen it happen elsewhere. The power of good old Mother Nature is pretty impressive.

Are the swans depleting their food source? Kenow and his research peers are studying that now. They have set up test plots in which some arrowhead beds are protected from feeding with 4x4-foot barriers. Researchers then take a 4-inch core sample, wash it, and compare tuber content to core samples from adjoining arrowhead beds. They found that the unprotected areas have 25 percent of the tubers that the protected spots do. But when the scientists returned in the summer, they found that about 60 percent of the vegetation had returned in the unprotected areas, not 25 percent. So the arrowhead beds are persisting despite the swan use. An adult swan eats an average of six pounds of tubers a day.

Is there disease from so many swans in a relatively small area? No, although scientists are keeping an eye on it. There is disease rampant in American coots and lesser scaups caused by intestinal parasites known as trematodes. The birds ingest them from faucet snails. The snails and trematodes are exotics, meaning not native to this area. Thatís why this is a new and disturbing phenomenon. From 2002 through spring migration 2005, 6,790 dead waterbirds were found, with total mortality estimated at 14,500 to 16,770. Workers found almost 600 sick/dead birds on Lake Onalaska last week. ìSuffice to say, we didn't find them all!î Nissen wrote to me in email on Monday. ìCoots (294) and lesser scaup (240) were again the two species most affected. Ring-necked ducks (32) were a very distant third.î

Do the swans stop here on their spring migration to their nesting grounds in the tundra? Yes, but they only stay a few days, and they are more spread out, so we donít notice them much.

What does the future hold for the swans? A big project is coming to the area south of Brownsville in 2007, if there is funding for it, Nissen said. Several islands will be built, which will provide thermal protection for the swans and the many other ducks that use the refuge. Mud flats and sand flats will be built too for loafing areas. Kenow pointed to a group of swans congregated on one muddy spot of the river on front of us. Thatís the kind of place swans like, he said, and more will be coming, if we can afford it.

To me, that funding is a no-brainer. Anyone who enjoys the forthcoming festival of swans will agree.

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