Before dawn on a mid-September morning, a small convoy of vehicles sits on a narrow trail in the woods at the Thief Lake Wildlife refuge. Five people wait quietly as the grey dawn crawls across the sky.
A sudden explosion that shatters the quiet morning is a call to action for the waiting DNR crew. A few hundred yards away, on the shore of a small stream, waterfowl specialist Jim Berdeen stands next to a net that's draped over more than 100 ducks. That explosion was small rockets that flung the net over ducks eating from grain spread on the ground.
The crew quickly unloads cages and fills them with ducks. They check each duck for age and sex and put a numbered metal band around one leg. A few of the ducks are tested for H5N1, the bird flu virus.
The testing is part of a nationwide surveillance program. Jim Berdeen says the DNR is working with the USDA to check a range of waterfowl species. They're focusing on birds from the Pacific flyway that come through Alaska to North America.
"We expect H5N1, if it enters North America, will come in from the Pacific flyway. So we want to focus on birds that have some chance of coming from Alaska," says Berdeen.
The numbered leg bands help biologists work on the waterfowl population puzzle. Hunters who kill banded ducks are asked to turn in the numbered band. That data helps estimate how many birds are killed each year. In addition, researchers fly over wetlands each spring to count breeding ducks for a population estimate.
Jim Berdeen says all the data is put into models which provide an estimate of duck population.
"You really can't predict how many birds are going to be harvested. There's a lot of different factors that feed into that," says Berdeen. "So our models have some utility, but they're not perfect, they're not all-encompassing."
Jim Berdeen lifts a young mallard, just beginning to show his trademark colors, from a cage.
"He's a male, his head's turning green, he's got this nice rusty brown breast and variegated feathers in his breast," says Berdeen. "So he's going from being a little guy to being a big guy."
Berdeen says he's seeing a lot more young ducks this year. And he's not the only one reporting a good duck crop.
DNR Waterfowl Specialist Steve Cordts does annual aerial duck surveys and works on duck population research. He says there's no hard data yet, but reports from across the state are encouraging. Lower water levels gave ducks better nesting sites.
Cold, wet weather during the past couple of springs has drowned nesting sites, and killed more ducklings.
"Across the state, people have indicated they've seen more duck broods than normal this year. I think it was generally a pretty good production year," says Cordts. "So even though breeding numbers are down, the number of ducklings that are out there will offset that."
Cordts says that could mean better than expected duck numbers for this fall's hunting season. But he says hunters will likely need to work a little harder to get to the ducks. The dry conditions will make it more difficult to get boats in the water.
Cordts says he won't know how much influence this year's good duck crop will have on overall duck numbers until the birds are counted when they start nesting next spring.