Courtesy of Brad Dokken and the Grand Forks (ND) Herald.

WATERFOWL MANAGEMENT: Predator trapping again under way

Effort near Kellys Slough, initiative to place nesting structures along U.S. Highway 2, part of puzzle to improve waterfowl production

By Brad Dokken
Herald Staff Writer

Predator trapping again is under way in a township-sized area near Kellys Slough National Wildlife Refuge as part of a longstanding project to boost waterfowl nesting success.

According to Roger Hollevoet of the U.S. Fish and Wildlife Service in Devils Lake, the refuge and surrounding land west of Grand Forks is one of 10, 23,000-acre sites in North Dakota being managed for predators this year. Bismarck-based Delta Waterfowl and the Max McGraw Wildlife Foundation of Dundee, Ill., are partners with the service in funding the predator-trapping program.

Other North Dakota predator-control sites are located in the Walhalla, N.D., area, along with Benson County and Towner County.

Record of success

According to Hollevoet, this is the sixth year trappers have removed predators such as skunks, raccoons and fox from the Kellys Slough area. The program, he said, has helped double and in some cases, triple or quadruple nesting success in the control areas. Waterfowl biologists long have used 20 percent as the benchmark rate of nesting success necessary to sustain a population.

"I can remember when we started this, we were finding a lot of sites that were in the 6 percent success" range without predator control, Hollevoet said. "Since we've been doing the trapping, we've been finding a lot of sites in that 15 to 20 percent range on up to 80 percent, and a lot of areas are 40 to 60 percent."

Last year, nesting success at Kellys Slough surpassed 57 percent, and Hollevoet said one control site near Cando, N.D., has sustained a five-year success rate of 70 percent.

"It seems like you always double it," he said of nesting success. "Our Cando site up there, over the five years, is off the charts. That kind of nesting success is just unheard of."

Sites being targeted for predator control include a mix of federal and private lands, Hollevoet said. A trapper from Mayville, N.D., is working the Kellys Slough site and began setting traps in mid-March.

Considering northeast North Dakota has some of the most abundant water conditions in the entire Prairie Pothole Region this spring, Hollevoet said the sites being targeted for predator control this year could be especially significant.

"From a duck production standpoint, we may have picked the right year to have all these blocks in this area, because I'm guessing we're going to be attracting a substantial number of (breeding) pairs," Hollevoet said.

Critical view

Despite its track record of success, predator trapping hasn't been without its critics. Ducks Unlimited, for example, has emphasized improving habitat as the key to waterfowl production. But according to Rob Olson, president of Delta Waterfowl, predator management should be looked at as another tool to benefit production at a time when waterfowl habitat is becoming increasingly fragmented.

It's been a key to improving waterfowl production at Kellys Slough, he said.

"When you think of all the tools the waterfowl manager has, we always start with habitat," Olson said. "Without habitat, you have nothing. At Kellys Slough, they started there, and then you go out and you check on it and say, 'how are the ducks doing?' And if habitat isn't enough, then you need to reach in your toolbox for something else. The art of it is choosing the right tool for the right place, and trapping just fits."

While this marks the sixth year of trapping at Kellys Slough, Hollevoet said research dates back about nine years, and trapping efforts in places such as Lake Alice National Wildlife Refuge began in the 1980s.

According to Olson, predator trapping is unique to North Dakota, although Delta intends to begin funding similar efforts next year in Canada. He said the trappers typically set between 200 and 400 traps at each of the sites, and for the next four months, the job is basically seven days a week.

"The reality is, if you look around the whole prairies, there are a lot of Kellys Sloughs out there," Olson said. "You can't trap everywhere, but you pick the key areas with high densities" of habitat and waterfowl. "You can go where the water is. (Predator management) is movable."

'Highway 2 Initiative'

Hollevoet of the Fish and Wildlife Service said "indirect predator management," such as fences and nesting structures, also figure into the strategy to boost waterfowl production. As an example, he cites a recent initiative in which service personnel, as part of a 10-year agreement with Delta Waterfowl, erected more than 100 nesting structures along U.S. Highway 2 between Petersburg, N.D., and Devils Lake, an area with numerous wetlands attractive to waterfowl.

Hollevoet said the service also worked with Delta to erect two "large clumps" of nesting structures in Cavalier County, an area of high-intensity cropland with limited nesting habitat.

He said both of the projects utilize "Delta-style" houses, which sit off the ground and feature a circular wire mesh frame covered with straw or other plant material to provide nesting cover.

"It was something that has a proven track record based on years of research that Delta has been doing, and other people have done a lot of research on nesting structures," Hollevoet said. "Nesting success is fairly high, and use is fair to excellent, depending on the years and locations.

"It's one little initiative to have some more success for waterfowl nesting."