Duck number decline blamed on dry habitat conditions
When the survey was conducted in May, pond counts had declined by 29 percent from last year on Canada's prairies and 16 percent on U.S. prairies.
The U.S. Fish and Wildlife Service's most recent duck population and habitat surveys show that duck populations have declined to 32.2 million birds, 11 percent below last year's count and 3 percent below the long-term average, said Don Young, Ducks Unlimited's executive vice president.
"These numbers pretty well reflect the feedback we've received all spring from our staff across North America," Young said. "An extremely dry winter left the soil so parched that almost all of the spring snow melt was soaked up and didn't run off into basins."
An important element in duck breeding success is the amount of water on breeding grounds. When the survey was conducted in May, pond counts had declined by 29 percent from last year on Canada's prairies and 16 percent on U.S. prairies. Southern Manitoba (up 10 percent) and Montana and the western Dakotas (up 25 percent) were the only exceptions.
"Conditions have improved markedly since the surveys were conducted," said Dr. Bruce Batt, DU's chief biologist. "We're seeing a very good late nesting effort on portions of the U.S. and Canadian prairies. Rainfall continued through early July, so good wetland conditions should persist through the brood-rearing period. This is a plus for the fall flight but, unfortunately, not as beneficial for ducks as snow that falls earlier in the year."
Three duck species remain of special concern for waterfowl managers: scaup (greater and lesser), American wigeon and northern pintail. Scaup numbers remained almost identical to last year at 3.8 million (up 2 percent). But scaup still are 39 percent below population goals. Wigeon have declined by 22 percent from last year and now are 33 percent below population goals. Pintail declined 15 percent to 2.2 million birds but are above the 1.8 million counted at their all-time population low of two years ago.
"This likely is the result of greatly improved pintail breeding habitat," Batt said. "This year they apparently held their own in the face of poor, dry habitat."
Mallard numbers are at 7.4 million, down 7 percent from last year and 9 percent below population goals. At 7.4 million, mallards are at an almost the same number as two years ago.
Other species showed mixed results. Gadwall (up 2 percent) and canvasbacks (up 11 percent) showed small increases. Redheads (down 5 percent), northern shovelers (down 22 percent), greenwing teal (down 8 percent) and bluewing teal (down 26 percent) all showed population declines.
Two factors resulted in the declines, Batt said.
"The late, cold spring likely interrupted migration for some species, especially the later nesters, and dry conditions caused tentative settling patterns by early nesting species. This makes it much more difficult than normal to project overall production and the fall flight that will originate from the breeding grounds. The improved conditions since the survey was made assure we're not dealing with a bust. But it won't be a bumper crop, either."