Waterfowl numbers still sky high despite dip
The first south-bound flights of blue-winged teal, vanguard of the autumn waterfowl migration, arrived in Texas just a week or two ago. That trickle will become a river in coming weeks as more bluewings leave their nesting grounds on the pothole-pocked prairies of the northcentral United States and southcentral Canada, pouring south toward wintering grounds on the Gulf Coast and beyond.
That river this autumn will likely carry a flood of bluewings. And behind them will come more waves of migrating ducks and geese. Millions more. According to recently released data from this year’s 62nd annual spring survey of waterfowl on the birds’ northern nesting grounds, most of North America’s duck and goose species continue enjoying what has been an unprecedented string of booming or at least stable populations.
This year’s annual aerial survey of the breeding population of the 10 most common duck species on northern nesting grounds estimated the total population at 47.3 million birds.
That index is slightly less than the 48.4 million birds estimated in the 2016 survey. But it is 34 percent higher than the long-term (1955-2016) average of the survey and marks the ninth consecutive year the total index has exceeded 40 million ducks.
In contrast, during the nine-year period from 198593, the total duck index was below 30 million, falling as low as 25 million in 1990 during the middle of a decade-long drought that saw prairie wetlands and grasslands crucial to duck mating, nesting and brood rearing wither, taking duck numbers with them.
Those wetlands, and the ducks, began returning in the mid 1990s, when heavy winter snows, abundant spring and summer rains, and aggressive grassland-focused efforts such as the federal Conservation Reserve Program combined to revitalize the prairie “duck factory.”
Bluewing boom
Blue-winged teal have been one of the duck species benefitting most from what has been two decades of favorable habitat conditions on those crucial nesting grounds. Bluewing numbers, which had fallen as low as 2.7 million in 1990 and triggered a multiyear closure of the September teal-only hunting season, have soared during the past 20 years.
This spring’s breeding population survey estimated 7.9 million bluewings in the survey area, up 18 percent from 2016 and a whopping 57 percent above the 1955-2016 average.
When bluewings’ spring population is above 4.7 million, federal waterfowl managers allow a 16-day September hunting season to allow harvest of the small ducks that migrate weeks ahead of other species. A nine-day season is allowed when populations drop below 4.7 million. The last time the bluewing population was below 4.7 million birds was 2005.
Texas’ 16-day 2017 teal season opens Sept. 9, with waterfowlers allowed to take as many as six teal per day, a change made in 2013 when the daily bag limit was increased from the four-teal limit that had been in place since the September teal-only season began in the mid 1960s.
When Texas’ regular 2017-18 duck season begins in November, waterfowlers will be allowed to take no more than one pintail as part of their six-duck daily limit. That’s down from a two-pintail limit in place during several previous seasons.
The reduction in the pintail bag limit was triggered last year, when the spring 2016 breeding population survey indicated pintail numbers had dropped to 2.6 million birds, just below the 2.7 million threshold federal waterfowl managers set as a minimum to allow a two-pintail limit.
Waterfowlers can look for that two-pintail bag limit to return for the 2018-19 season. This year’s spring survey estimated pintail numbers increased 10 percent from the previous year, to about 2.9 million birds.
Despite their year-overyear increase, pintail numbers remain 27 percent below the long-term average. The big, graceful ducks, much prized by Texas waterfowlers and a common wintering species on the state’s coastal prairies and shallow coastal bays, are one of only two major duck species that have not rebounded from steep declines in the late 1980s and early 1990s.
Scaup — bluebills to most Texas waterfowlers — are the other laggards. Scaup this year saw a 12 percent drop in their estimated population in the annual spring survey, falling from 5 million birds in 2016 to about 4.4 million this year. That leaves the hardy diving ducks 13 percent below their 61-year average.
Populations of the other eight major duck species surveyed remain above — sometimes far above — that long-term average.
Mallards, the most populous duck in North America, saw their population drop 11 percent this year, to 10.5 million birds. But that’s still 34 percent above the long-term average.
Wigeon numbers fell a surprising (and somewhat alarming) 19 percent from 2016 numbers. But the birds remain 6 percent above their long-term average.
Green-winged teal numbers in the survey area declined 16 percent but remain a stunning 70 percent above the 19552016 average.
‘Boggles the mind’
Redheads, one of the most important ducks for Texas coastal waterfowlers because the bulk of North America’s redhead population winters on the shallow, vegetation-rich bays along the state’s middle and lower coast, also saw a significant decline this year, dropping 13 percent. But the birds remain 55 percent above the long-term average.
Canvasbacks numbers held steady, declining only 1 percent and remaining 25 percent above their long-term average.
Gadwall and shovelers, two of the most common ducks taken by Texas waterfowlers, enjoyed good year-over-year increases, with gadwall numbers up 13 percent and “spoonies” up 10 percent. Gadwall numbers are more than double (111 percent) their long-term average, while shovelers are 69 percent above the 61-year average.
“Yes, total numbers declined a little this year from the year before. But we’re still talking about more than 47 million ducks!” said Dave Morrison, deputy director of Texas Parks and Wildlife Department’s wildlife division and long-time waterfowl program leader for the agency. “Those of use who remember what it was like in the late ’80s and early ’90s, when we had a three-duck limit and a 39day season in Texas, know how lucky we’ve been these last several years. It just boggles the mind that we’ve had such a long run of high duck numbers.”
That applies to goose populations, too. While dramatic shifts in wintering areas have meant Texas’ coastal prairies and marshes have seen the number of geese wintering there decline significantly over the past two decades, North America’s goose population has boomed.
The Waterfowl Population Status, 2017 Status of Waterfowl report, issued this past week by the U.S. Fish and Wildlife Service, indicates eight of North America’s 27 goose and tundra swan populations had statistically significant population increases during the past 10 years. And none of those 27 goose populations has seen a significant decline during the past decade.
Two goose populations important to Texas waterfowlers have climbed during that period. The mid-continent population of lesser snow geese has increased about 4 percent during the past decade, and the mid-continent population of greater white-fronted geese — speckled-bellies to waterfowlers — has climbed 5 percent.
Overall, habitat conditions on northern nesting grounds continued to be very favorable for waterfowl this spring. The annual aerial survey of major waterfowl nesting areas stretching from the northcentral U.S. through prairie and boreal forest in Canada and into Alaska indicted the abundance of wetlands increased 22 percent from 2016, to 6.1 million “ponds.” That number is 17 percent above the long-term average.
Some areas held those advantageous habitat conditions through the mating and nesting season, meaning birds almost certainly pulled off successful hatches. Portions of Canada’s prairie pothole country remained extremely wet and lush through summer.
Drought threatens
Not all the news from the “duck factory” is positive. Drought, an inevitability on the prairies, appears to be trying to establish itself after a two-decade absence in the north-central U.S. Habitat conditions in the Dakotas and eastern Montana, the heart of U.S. duck nesting country, were only fair this spring and have significantly deteriorated over the summer. Much of Montana and North Dakota has fallen into severe or extreme drought during the past month, with reports from the area indicating most of the small wetlands and many of the mid-size wetlands have evaporated. Duck numbers and nesting success in the affected regions took a nosedive.
But even with the deteriorated conditions on some of the best U.S. prairie pothole country, this year’s fall flight of waterfowl to wintering grounds in Texas should be another excellent one, Morrison said.
“These really are the best of times,” he said. “We know it can’t last forever. And it won’t. But right now, things are very good. We waterfowlers need to be thankful for that.” shannon.tompkins@chron.com twitter.com/chronoutdoors