Data on duck populations full of positives and negatives

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Data on duck populations full of positives and negatives
Numbers short of estimates, but rain provides boost
By SHANNON TOMPKINS

Texas waterfowlers looking to divine some insight into what to expect for this autumn's duck seasons can be excused if they read mixed signals in the just-released data on duck breeding populations and habitat conditions on the major nesting grounds of the north-central United States and prairie Canada.

Overall estimated population of the 10 major duck species is about the same as a year ago — 31.7 million, statistically similar to the 2004 estimate of 32.2 million ducks. But look closely at the population estimates for individual species and data on habitat conditions, and things become a bit murky. Mallards, the continent's most common duck and the species that drives much of the annual regulatory process, are down — this year's estimate of 6.8 million birds is the lowest mallard index in more than a decade and down more than a third from 1999's estimated population of 10.8 million mallards.

Pintails, not so long ago the premier ducks on Texas coastal prairies and marshes, saw an encouraging bump in population but remain barely half as numerous as they were in the 1970s. Estimates of gadwall population were down 16 percent from a year ago. But the "gray ducks," which have become a primary species for Texas waterfowlers, remain well above their long-term average. Blue-winged teal, which account for a majority of the ducks taken early in the regular duck season and almost all of the birds harvested in the September teal-only season, saw a good population increase this year.

But the increase, from 4.1 million to 4.6 million, was about 100,000 birds short of the 4.7 million bluewings required to expand the September teal-only season from nine to 16 days. Six of the 10 major duck species recorded breeding population declines. Four saw increases.
And the population of three of the four species that increased remain below their target population as set in the North American Waterfowl Management Plan.

This year's 31.7 million ducks are more than 10 million fewer than estimated just a decade ago. But that's the pessimistic stuff. There's plenty on the positive side of the ledger, too. While this year's estimate is nowhere near the 40-plus million of the mid-1990s, it's much better than the 25-27 million ducks that hit the nesting grounds in the late 1980s and early 1990s at the peak impact of a decade-long drought in those areas.
More encouraging, weather appears to have given ducks a big break.
When the first migrating ducks hit the prairies this spring, they found depressingly dry conditions, particularly in the north-central U.S.
For early-nesting species such as mallards, this was not good news.
But by the middle of May, "Nature turned on the faucet," said Dave Sharp, the U.S. Fish and Wildlife Service's representative to the Central Flyway Council.

Lots of rain fell on the Dakotas and southern prairie Canada beginning about the third week of May and continuing through June — just as the USFWS and Canadian Wildlife Service were conducting their annual joint waterfowl population and habitat surveys. Water is a crucial element for nesting waterfowl. It provides temporary "sheet" water and temporary shallow wetlands, plus recharges deeper, mostly permanent wetlands — all important for pairing, providing invertebrates for food and open water for brood rearing and molting. Water is also crucial for fueling growth of grass and other vegetation that provides nesting cover for hens.

This summer, ducks are awash in water.

This is particularly true in much of prairie Canada, where dry conditions coupled with dwindling grasslands have over the past few years spelled serious problems for ducks such as pintails, birds greatly dependent on the quality and quantity of habitat in Alberta and western Saskatchewan.
The May "pond counts" in prairie Canada and the parkland (mixed grassland/forest) region to its north showed an index of 3.9 million "ponds." This was up more than half from the 2004 estimate of 2.5 million ponds in Canada and about 12 percent above the long-term average of 3.3 million Canadian ponds. The May estimate of wetlands on the U.S. portion of the traditional survey area was 1.5 million ponds, very similar to 2004 numbers. The pond count for the main duck-producing areas in Canada and the United States was up 37 percent from a year ago.
And that doesn't take into account the additional wetlands created in the Dakotas from rains that fell after the pond counts, Sharp said. "I really have to believe that we're going to see better production and recruitment this year than we did last year," Sharp said. "The habitat conditions are so much better in a lot of areas."

In particular, the parkland habitat looks outstanding.

"Almost all areas look good, but the parkland has to be the standout," Sharp said. "It hasn't been in this good a shape in a decade." While the prairies get a lot of deserved attention for their importance as duck producers, the parklands are equally important, particularly for some species. Wigeon, scaup, ringnecks and a considerable number of mallards make use of the parkland habitat, Sharp said. Those birds should see good production this summer. Also, the late-spring/early-summer rains that blessed the prairies bode good things for late-nesting species such as gadwall and bluewing teal. "I imagine that's going to help Texas hunters," said Dave Morrison, waterfowl program leader for the Texas Parks and Wildlife Department. "Bluewings and gadwall are a couple of our bread-and-butter birds."

Also, the abundance of water nearly guarantees improved success for ducks that lose their first nest and attempt second efforts. Re-nesting efforts inevitably result in smaller egg clutches and lower duckling survival. But the good habitat conditions in most areas this summer should improve odds for those second nests. Waterfowl managers are looking at that right now. Biologists this month are conducting production surveys — brood counts — across the major duck-producing areas. Those brood counts won't be as wide-ranging as in past years — budget cuts to migratory waterfowl monitoring programs are to blame.

But what information is sifted from those production surveys will be added to the breeding population estimates, pond counts, harvest estimates from this past season and other data to provide the basis for hunting proposals for the 2005-06 duck seasons.

Those proposals will come late this month, when the U.S. Fish and Wildlife Service's regulations committee meets in Washington.