To the untrained eye, they look like hockey pucks. But from the passenger seat of a Partenavia twin-engine aircraft, Jay Hitchcock, with the rapid-fire delivery of an auctioneer, catalogues all the birds he sees on the ground and paddling in the water, some 45 metres below.
"Redhead, a drake, gadwall a pair, blue-wings a pair, Canada goose a pair, mallard a pair, Canada goose one, ruddy ducks a pair, redheads a pair, mallards two pairs," he says, barely pausing to take a breath as he carries on for another 40 seconds listing dozens more ducks and geese.
Flying low around Lethbridge, Alta., on a recent hot, blue-sky day, the 31-year-old U.S. Fish and Wildlife Service biologist from Arkansas was taking part in the continent's annual waterfowl census. He is one of dozens who each May take to the air – and ground – in what is considered the world's largest co-ordinated wildlife survey.
This mammoth accounting – carried out by both the U.S. and Canadian governments in conjunction with state and provincial governments, First Nations, and with the help of special-interest groups – is designed to keep tabs on the continent's waterfowl breeding populations and associated wetland habitat. Waterfowl counts take place each spring stretching from Alaska, across the Canadian Arctic, down through the Prairies all the way to the Maritimes and south to portions of the U.S. – in total covering about 5.4 million square kilometres, which is most of the main waterfowl nesting areas in North America.
However, fixed-wing aircraft and helicopters along with ground surveys only get to a fraction of the total area. After the birds are eyeballed, estimates are generated, corrections are made between the air and ground figures, and, using complex mathematical formulas, projections of breeding populations for dozens of duck and geese species are pumped out. This detailed data generated by the "duckheads," as they unabashedly refer to themselves, is in turn used to guide government policies around hunting and land management.
"It's really the envy of wildlife biology throughout the world," said David Howerter, national manager of research with the Institute for Wetlands and Waterfowl Research for Ducks Unlimited Canada, which has been involved in the survey for decades, contributing both staff and financing. "Ducks are good harbingers of what's going on with the environment," he added. "If populations are going up that's a good sign, but if they're going down, we want to understand why they're going down."
Last year, the survey offered a surprising snapshot: Despite ongoing concerns about a negative impact of climate change on waterfowl populations, a record 48.6 million waterfowl were counted (7 per cent higher than the year before and a 43-per-cent increase over the long-term average), the most since the annual survey began in 1955. Scientists credited a series of good, wet weather cycles for creating wetlands ideal for breeding, as well as joint habitat conservation efforts for the bumper crop of ducklings and goslings that have grown old enough to count.
"It is good news," said biologist Joel Ingram, head of population management with the Canadian Wildlife Service for the Prairie and Northern region. "Recent trends in waterfowl are most species are near or above conservation goals."
But he said the survey has also been useful to highlight species that need special attention. "Northern pintail and lesser scaup are two species that are common and breed in Canada and their populations have seen some decline and they're receiving additional research," he said.
The survey also assesses wetland habitats across the Canadian Prairies and the north-central U.S. and last year reported the total estimates for ponds, known as "pot holes," was 32 per cent lower than 2011. Still, the pond number was pegged at about 5.5-million, plus or minus 200,000, slightly higher than average over the long term.
Officials also said all this data feeds into the North American Waterfowl Management Plan, which was signed by Canada and the U.S. in 1986 and by Mexico in 1994, in response to "critically low numbers of waterfowl." (Canada and the U.S. first signed a convention on migratory birds in 1916, and have been working together to protect them since then.)
Brad Bortner, chief with the division of migratory bird management with the U.S. Fish and Wildlife Service, said the efforts help all three countries determine where habitat needs to be protected, and dictate bag limits and hunting seasons. Through hunting licences and outfitting, game birds are big business.
"We have had success, but as ever we need to remain vigilant and make sure that we can sustain those populations," Mr. Bortner said.
Back in Lethbridge, it's too soon to predict what this year's count will bring.
"People think it's maybe just a bunch of duckheads just counting ducks," said 59-year-old pilot/biologist Jim Bredy of New Mexico, now in his 26th season of the spring count with the U.S. Fish and Wildlife Service. But a whole series of birds and mammals rely on the wetlands that are affected by the survey, he explained.
"We need to know what our inventory is before we can set some realistic and manageable harvest regulations for the waterfowl population that don't know there's a border between two countries – they just know [it] as one habitat."