Biologists keep a rough count of region’s waterfowl

The small airplane buzzes over the waterfowl marsh, banking and circling almost like one of the ducks or geese below.

Inside that aircraft, waterfowl biologist Andy Raedeke watches intently and jots down numbers in a notepad.

Raedeke, who works for the Missouri Department of Conservation, is playing “I Spy” in the sky. He is getting a bird’s-eye view of how the migration is progressing at wetlands managed by his agency.

Based on years of training and experience, he is counting ducks and geese on a conservation area and getting an idea of how the habitat is looking. An exact science? Hardly. Raedeke knows he will never come close to counting every duck or goose using a wetlands area.

But he also knows that he can give hunters and waterfowl area managers a good idea of trends and how many ducks are using an area.

“It’s as much an art as it is a science,” Raedeke said. “We’re going 80 to 100 miles per hour when we fly over. Say, there’s a block of ducks down there, packed tightly. There’s no way you are going to get an exact count.

“If we’re within 20 percent, we’re doing well.”

Still, Raedeke has learned to block off transects in the marsh and make estimates of how many ducks each area is holding. He tests himself by taking photos, then comparing his estimates with what the photos show. Generally, he is pretty close.

He and others are helped by computer programs that train counters and by lots of experience. The Department of Conservation flies surveys every other week, and gets ground counts every week. Frank Nelson, a biologist in southeast Missouri, gathers data and puts out reports. He also conducts aerial surveys in that part of the state.

In Kansas, most of the waterfowl surveys are ground counts. Their accuracy often depends on the size of the area being surveyed, said Tom Bidrowski, migratory bird manager for the Department of Wildlife, Parks and Tourism.

“On a small wildlife area, someone can get on a high spot and see most of the wetlands,” Bidrowski said. “But at someplace like Cheyenne Bottoms, where you have a lot of water and cover and you have a cryptic species like blue-winged teal, it’s tough.

“They get back in that vegetation, and they’re just hard to see.”

That’s why wildlife managers at large areas such as Cheyenne Bottoms often hedge on ducks numbers. This week, for example, they listed numbers as 20,000 to 35,000 ducks.

Some hunters chuckle when wildlife areas or refuges estimate duck numbers down to the bird. At Squaw Creek, for example, the latest count from U.S. Fish and Wildlife Service employees lists 71,964 ducks

Similar seemingly exact counts are issued by the Department of Conservation. But Raedeke says hunters should not imply that every duck was counted.

“We jot down numbers in notepads, then add up totals at the end,” he said. “We just list the totals of what we find.”

This story was originally published November 7, 2015 at 3:34 PM with the headline "Biologists keep a rough count of region’s waterfowl."