Most waterfowl enjoying population surge
The full moon later this week should trigger the first trickles of what in September will become a river of blue-winged teal flowing south into Texas from the prairies of the north central United States and south central Canada, North America’s “duck factory.” That avian river might be a tad shallower than last year — down by as much as 22 percent — but it still will be one of the largest numbers of bluewings to move south in the last 60-plus years. The little ducks, and almost all North American waterfowl, continue riding a population boom tied to an unusual two-decade run of great-to-good habitat conditions on nesting grounds.
“We’re still seeing strong populations of most ducks — record or nearrecords for some,” said Kevin Kraai, waterfowl program leader for the Texas Parks and Wildlife Department. “There was a little drop this year but really no significant change in overall numbers.”
That is Kraai’s basic assessment of the “Waterfowl Population Status, 2016,” the report on duck and goose breeding populations and habitat conditions compiled from annual aerial surveys, satellite imagery and onthe-ground observations of the continent’s major waterfowl nesting areas.
Data from the aerial survey to assess breeding populations of North America’s 10 major duck species and wetland abundance/condition, conducted each May/June since 1955 and covering more than 2 million square miles in the north central U.S., much of Canada and Alaska, indicates a duck breeding population index of 48.4 million birds.
That number is down about 2 percent from the 49.5 million ducks estimated in 2015 — the highest index in the 61-year history of the survey and a whopping 38 percent above the 1955-2015 average. Decline in wetlands
Despite offering the good news of continued high population, the report, released last week, reveals mixed news for waterfowl and waterfowl hunters. Most concerning was the decline surveyors noted in wetlands on much of the major duck nesting regions of the U.S. prairies, and prairie and park land in Canada.
The “pond count,” which annually tallies the numbers of a variety of wetlands, saw a steep decline in the total number of wetlands, especially the ephemeral “sheet water” and small wetlands so hugely important to some species of ducks such as pintails. The total count of wetlands over the survey area was 5 million “ponds,” down a depressing 21 percent from the previous year and slightly below the long-term (19552015) average of 5.3 million.
The largest decline was noted on the U.S. north central prairies where pond count dropped from 2.2 million in 2015 to 1.5 million — a 30 percent fall that put wetland numbers there 11 percent below the long-term average.
Canada’s pond count dropped 16 percent from 2015 and was right at the long-term average.
The decline in wetlands on the U.S. prairies is sobering for its potential effects on breeding and nesting success of pintails and blue-winged teal, hugely important species to Texas hunters. Those birds and other ducks depend heavily on the health of prairie wetlands.
Duck numbers can quickly tumble if dry conditions, as those seen there last winter and early spring, persist. Amultiyear drought on northern prairies in the 1980s and early 1990s helped the duck population index fall to barely 25.07 million in 1990 — the secondlowest total since 1955 and the trigger for the most restrictive duck-hunting regulations in a generation. Seasons were cut to a mere 39 days, and a threeduck daily bag limit was enforced in the late 1980s and early 1990s.
Habitat conditions on much of the northern prairies got a boost soon after the survey was completed, Kraai said.
“Some areas saw a lot of rain and even some flooding in early summer, so conditions improved greatly,“Kraai said. That could boost chances of ducks pulling off successful late nesting efforts.
Of the 10 duck species counted during the spring aerial surveys, half showed population increases from 2015 and half saw declines.
The breeding population of mallards, the most populous duck species in North America, rose 1 percent from 2015 to 11.79 million — the highest population index in the survey’s 61-year history. The mallard population is estimated to be 51 percent above its long-term average.
Other ducks that saw breeding population increases this spring were: wigeon, up 12 percent from 2015, and 31 percent above long-term average; green-winged teal, up 5 percent to a record 4.2 million birds and 104 percent above long-term average; redheads up 8 percent and 82 percent above longterm average; and scaup, up 14 percent and right at their long-term average of 5 million birds. Blue-wing numbers off
Blue-winged teal saw the largest decline from 2015 numbers, falling 22 percent to 6.69 million birds. But that still is 34 percent above the long-term average and far above the 4.7 million birds federal waterfowl management protocols require to allow states such as Texas to hold a 16-day, teal-only hunting season during September. If blue-wing numbers drop below 4.7 million, the teal season is reduced to nine days, and the six-teal daily bag limit can be reduced.
Gadwall (down 3 percent), shovelers (down 10 percent), canvasbacks (down 3 percent) and pintails (down 14 percent) were other duck species that saw declines from 2015 numbers. But all except pintails remain well above long-term averages.
Pintails are the only duck species that has not seen a strong rebound in population after wet conditions returned to northern prairies in the mid 1990s and continued in an unprecedented drought-free string for the past two decades. The big ducks, which have been a staple of Texas coastal hunters for generations, are 34 percent below their long-term average.
This year’s decline in pintails and blue-wings counted during the survey may not be as significant as they appear, Kraai said. Both species are prone to “over fly” their traditional prairie breeding/nesting areas if habitat conditions aren’t conducive to successful nesting, he said. The birds could have settled in suitable habitat outside the traditional survey.
“It will be interesting to see if those birds shifted areas,” he said.
Most goose populations continue to boom, including the species most commonly wintering in Texas. The midcontinent population of snow and blue geese had a winter population of about 3.5 million — more than triple the 1 million birds counted during midwinter surveys in the early 1970s and up 5 percent from the previous year. Ross’s geese, a smaller “light” goose,” also have enjoyed a booming population, with a single colony in the Arctic holding around 700,000 birds.
Goose-nesting success is tied to weather conditions, with early spring helping production and a late spring with persistent ice/snow cover hurting gosling production. This year conditions look good for at least average production, Kraai said. The same applies to white-fronted geese, he said.
“From reports, it sounds like whitefronts will have average or above average production,” he said.
Goose numbers on nesting grounds are hard to figure since the birds nest over huge expanses in remote areas of the Arctic and sub-Arctic, where meaningful surveys are not logistically and economically possible. Waterfowl officials will not have a good idea of how those bird birds did over the nesting season until they begin moving south, staging in areas of southern Canada during October. Rains have been a plus
When those waterfowl — ducks and geese — get to Texas, they likely will find some of the best habitat conditions they have found here in years.
The combination of wet conditions across much of Texas this spring and early summer greatly aided wetland habitats, especially on the coastal prairies and marshes where swamping rains and flooding charged wetlands with freshwater and nutrients, triggering a flush of aquatic vegetation crucial to wintering waterfowl. Also, heavy rains that recharged reservoirs and rivers have loosened water restrictions on rice farmers whose fields provide crucial habitat for wintering waterfowl.
“There could be as much as 50,000 acres or more rice on the coastal prairie this year than there was just a couple of years ago,” Kraai said. “With that and the improvement in wetlands from the rains we’ve had, carrying capacity goes way up. Things could certainly change between now and when the birds get here. But, right now, a lot of the state is looking better, habitatwise, than it has in years. Let’s just hope it stays that way.”