Duck populations are up again this year in response to
improved habitat conditions on the breeding grounds
By Matt Young
From September / October Issue of Ducks Unlimited
Magazine
Extensive field research has shown that
ducks need a combination of two things to consistently have good breeding
success: extensive, undisturbed nesting cover and healthy, seasonal wetlands.
Yet, even in areas with this ideal mix of habitat, duck production is often
limited by a lack of water, especially in the semi-arid prairie pothole country
of the United States and Canada.
Consequently, in 2007, continental duck populations got a big boost from
exceptionally wet spring weather on the prairies, which maintained or improved
waterfowl habitats across much of the region. The U.S. Fish and Wildlife
Service (USFWS) reports that May pond numbers—the barometer for wetland
conditions on the prairies—increased 15 percent from 6.1 million ponds in 2006
to 7 million ponds in 2007.
Most duck populations responded to the abundance of water with an
impressive breeding effort. The 2007 breeding population estimate for the 10
most common duck species in the traditional survey area was 41.2 million
birds—a 14 percent increase from 2006 and the fifth-largest estimate since
surveys began in 1955. In more good news for waterfowl hunters, breeding
populations of redheads, canvasbacks, and shovelers
soared to record highs. Mallards had a breeding population of 8.3 million
birds—up 14 percent from last year and the largest estimate since 2000.
Gadwalls, blue-winged teal, and green-winged teal also had healthy increases in
2007 and were well above their long-term averages. And wigeon,
which have lagged behind many other duck species in recent years, jumped 29
percent to the highest level since the late 1990s. Only scaup
and pintail numbers remained similar to last year and below population
goals.
“Waterfowl hunters who remember the long prairie droughts of the past, some of
which lasted a decade or more, know that wet years don’t come very often on the
prairies,” says DU Executive Vice President Don Young. “And it’s encouraging
that we still have the habitat base to support historic populations of many
duck species when water conditions are favorable. Hopefully, fall weather will
cooperate, and DU supporters will see the fruits of their labor in the form of
impressive flights of waterfowl from their blinds this
season.”
May pond counts and waterfowl breeding population estimates are compiled during
extensive air and ground surveys conducted by the USFWS, Canadian Wildlife Service,
and state and provincial wildlife agencies. Although annual duck and goose
surveys have important implications for waterfowl hunters, especially in
determining hunting regulations, they do not necessarily predict individual
hunting success. Weather and local habitat conditions often influence hunting
success in many areas of the continent more than the size of the fall flight.
Keeping that in mind, the following is a comprehensive report on waterfowl
populations in each flyway based on reports from DU and government biologists
in the field.
PACIFIC FLYWAY
The majority of Pacific Flyway waterfowl are raised on the
prairies of the United States
and Canada, as well as in Alaska, northwestern Canada, and other western states. Alberta is a vital
breeding area for continental waterfowl populations, but is especially
important to Pacific Flyway waterfowl. In 2007, an estimated 4.3 million
breeding ducks were surveyed across the prairie and parkland regions of
southern Alberta.
This year’s population was similar to the 2006 estimate and the long-term
average. Among individual species, mallards, pintails, gadwalls, wigeon, blue-winged teal, and scaup
declined, while green-winged teal, shovelers,
redheads, and canvasbacks increased.
DU Canada biologist Ian McFarlane reports that habitat conditions were
generally favorable in 2007 for breeding waterfowl across southern Alberta. “Frequent
spring precipitation provided improved nesting cover this year,” McFarlane
says. “Nest success appears to have responded accordingly, and brood habitat
was in great condition. DU field staff reported sighting a brood on every pond
in many areas. As a result, above average waterfowl production is anticipated
in Alberta
this year.”
To the north, in the Peace parklands and boreal forest of northern Alberta, northeastern British
Columbia, and the Northwest
Territories, breeding ducks increased 20 percent in
2007. All species that traditionally breed in this region including mallards, wigeon, green-winged teal, and scaup
showed population increases. In Alaska and the
Yukon Territories,
total breeding duck numbers were up 20 percent and were an impressive 59
percent above the long-term average. This included 1.1 million breeding
pintails—a 9 percent increase from last year’s estimate.
In the western continental United
States, waterfowl habitat conditions were
highly variable. “In California,
the outlook for breeding waterfowl was really poor this year,” says senior DU
biologist Dr. Fritz Reid. “We had some fair duck production in the Sacramento Valley
and in the Suisun Marsh, but overall the Central Valley
suffered from severe drought. The dry conditions adversely affected every
aspect of the waterfowl breeding cycle, from nest initiation to nest success to
brood survival. But elsewhere in the Intermountain West, wetland conditions
improved as you moved north. Waterfowl production was probably pretty good in
the Great Salt Lake area, as well as in much of Idaho,
Washington, and Oregon, which are important breeding areas
for cinnamon teal, gadwalls, and divers.”
This was a generally good year for goose production in the Pacific Flyway, and
most populations should have a fall flight similar to last year. Favorable
spring weather and nesting conditions in Alaska’s
Yukon-Kuskokwim Delta should result in increased fall populations of cackling
and white-fronted geese in the Pacific Flyway, while dusky Canada goose numbers
should be down this fall because of harsh spring weather and increased
predation by bald eagles on their breeding grounds in the Copper River Delta.
CENTRAL FLYWAY
The Central Flyway receives most of its waterfowl from the
prairies, with the majority of ducks coming from Alberta,
Saskatchewan, Montana,
North Dakota, and South Dakota. Most of the flyway’s geese, as
well as most of its scaup, wigeon,
and green-winged teal, are raised in the western boreal forest and Arctic of
Canada and Alaska.
Saskatchewan consistently ranks at the top of North America’s most important waterfowl breeding areas.
In 2007, habitat conditions ranged from excellent in the parklands to fair in
southern parts of the province near the U.S. border. Total duck numbers in
southern Saskatchewan
were up 9 percent this year and exceeded 11 million birds for the first time
since 1976. In fact, Saskatchewan
alone supported more than a quarter of the mallards and pintails and more than
a third of the blue-winged teal, gadwalls, shovelers,
redheads, and canvasbacks in all of the traditional survey area.
DU Canada biologist Dr. Michael Hill reports that large numbers of breeding
birds, coupled with favorable wetland conditions, likely resulted in above
average duck production in Saskatchewan.
“In the parklands, frequent rains kept many seasonal wetlands flooded well into
summer, providing excellent habitat for breeding pairs and broods,” Hill said.
“In July, DU field staff observed many older broods of mallards, pintails, and
canvasbacks, as well as many younger broods of various species, indicating
there was a strong breeding effort.”
In the Great Plains states, habitat conditions for breeding waterfowl were
variable, but better than average overall, especially in the eastern Dakotas, where widespread flooding occurred this spring.
In North Dakota,
total breeding ducks jumped 23 percent from 3.9 million birds in 2006 to 4.8
million birds this year. Duck numbers were up even more in South Dakota, increasing by an impressive 72
percent from 2.1 million birds in 2006 to 3.7 million birds in 2007. And
another 1 million breeding ducks were surveyed across Montana. This year’s duck population in this
state was similar to the 2006 estimate and the long-term average.
Senior DU biologist Dr. Jim Ringelman reports that
waterfowl habitat conditions improved across much of North
Dakota and South Dakota
after May waterfowl surveys were conducted. “We had fairly dry conditions early
in many areas, because we were just coming out of a pretty severe drought,” Ringelman says. “There was decent snowmelt, but most of the
water just soaked into the soil. It took a series of heavy rains in late May
and into June to really recharge the seasonal wetlands. Although the
improvement in water conditions may have come a little late for early nesters,
it provided great conditions for renesting and
late-nesting birds and provided almost optimal conditions for brood survival.
While driving around this summer, I saw many large broods. Typically, hens lose
about half their ducklings, but this year, I saw many broods in which up to 80
percent of the ducklings appeared to have pulled through. The strong late
nesting effort along with good brood survival should have resulted in good
waterfowl production in the Dakotas this
year.”
Breeding success among Central Flyway goose populations was variable in 2007.
On the prairies, spring flooding may have caused some Canada goose nest losses,
but prairie goose populations remain above the long-term average. In the north,
harsh spring weather reduced production of tallgrass
prairie and shortgrass prairie Canada geese
and midcontinent light geese (including lesser snow
and Ross’s geese). Midcontinent white-fronted geese
also had reduced production in 2007, but population increases in previous years
should result in a fall flight similar to that of 2006.
MISSISSIPPI
FLYWAY
The majority of Mississippi Flyway waterfowl are raised on the
prairies of the United States
and Canada, as well as in
the western boreal forest and the Great Lakes
region. Manitoba
is among the most important waterfowl breeding areas in the Mississippi Flyway.
In 2007, total breeding ducks in southern Manitoba declined 26 percent from 1.8
million birds in 2006 to 1.3 million birds in 2007. However, populations of
mallards, gadwalls, redheads, canvasbacks, and shovelers
remained near or above the long-term average, while wigeon,
green-winged teal, blue-winged teal, pintails, and scaup
were below average.
DU Canada biologist Mark Francis reports that heavy rains improved wetland
conditions across southern Manitoba
after May waterfowl surveys were conducted. “Most seasonal wetlands and even
some temporary wetlands were flooded in late May and June, providing good
habitat for late-nesting ducks and renesting birds
and excellent habitat for brood-rearing,” Francis says. “DU staff observed many
broods of various species and ages this summer, indicating that nest success
was good overall, and brood sizes appeared to have been larger than in most
years.”
In the boreal forest of western Ontario,
northern Manitoba, and northern Saskatchewan, total duck
numbers increased 18 percent in 2007. DU Canada biologist Scott Muir reports
that waterfowl production appears to have been good in Ontario,
a major waterfowl production area for both the Mississippi
and Atlantic flyways. “Spring
wetland conditions ranged from good in the southwestern portion of the province
to very good throughout the central and southeastern regions,” Muir said. “In
southern Ontario,
water levels in most permanent wetlands receded during the summer, but most of
these habitats remained sufficiently wet to support developing broods. In
contrast, northern Ontario
received above average precipitation in June, which recharged wetlands and
provided abundant brood-rearing habitat. Numerous brood sightings, including
reports of many young broods, suggest there was a strong, sustained breeding
effort in the province this year.”
Mallards raised in the Great Lakes states (Minnesota, Michigan, and Wisconsin)
make up a large part of the waterfowl harvest in the eastern Mississippi
Flyway, as well as in the mid-Atlantic region. In 2007, total mallard numbers
in the Great Lakes states were up by 27
percent from 588,000 birds in 2006 to 746,000 birds this year. Total duck
numbers increased significantly in Michigan
and declined slightly in Wisconsin and Minnesota.
DU biologist Dr. John Coluccy reports that dry spring
and summer weather may have had an adverse affect on duck production in the Great Lakes states. “Water levels are generally more
stable in the Great Lakes region than on the
prairies, but this year was dry enough that a lack of water may have reduced
brood survival in many areas,” Coluccy said. “On a
positive note, the dry weather has benefited many of our larger marshes by
drawing down water levels and encouraging germination and growth of moist-soil
vegetation, which should provide good migration habitat for waterfowl this
year.”
This was a generally good year for Mississippi Flyway Canada goose populations.
Breeding success among Mississippi Valley, Southern James Bay, and Eastern Prairie Canada geese
was average to above average, and these populations should have fall flights
similar to or larger than in 2006. But as in the Central
Flyway, poor breeding success among lesser snow and Ross’s geese in 2007 will
likely result in reduced numbers of these birds in the Mississippi Flyway.
White-fronted goose numbers should be similar to last year.
ATLANTIC FLYWAY
The Atlantic Flyway receives most of its waterfowl from the
eastern United States and Canada, with
the exception of a few species such as canvasbacks and redheads, which are
largely raised on the prairies. In 2007, the total breeding duck population in
the eastern survey area (covering eastern Ontario,
Quebec, Atlantic Canada, Maine,
and northern New York)
was 2.5 million birds. This estimate included 651,000 breeding ring-necked
ducks, 569,000 breeding black ducks, and 443,000 breeding mallards. Populations
of most duck species including black ducks, mallards, green-winged teal, and
ring-necked ducks were similar to or larger than last year’s estimate and the
long-term average.
DU Canada biologist Wade Lewis reports that weather and habitat conditions were
generally favorable for breeding waterfowl in the provinces of New
Brunswick, Nova Scotia, and Prince Edward Island.
“Timely rains helped maintain water at normal levels on the majority of
DU-managed wetlands in Atlantic Canada,” Lewis said. “Brood surveys indicate
that many early nesting attempts were successful. Late broods were also sighted
in some areas, but overall waterfowl production and brood sizes appeared to be
average or above average throughout the region. In addition, seasonal summer
temperatures and weather should have helped many of the ducklings in those
broods survive to fledge.”
In northern Quebec,
breeding pair counts of Atlantic Population Canada geese increased 22 percent
from 160,000 pairs in 2006 to 195,700 pairs this spring, and the total spring
population of 1.2 million birds was up 8 percent from last year. Unfortunately,
harsh spring weather delayed nesting activity and reduced breeding success.
Overall, Atlantic Population Canada geese should have a fall flight similar to
last year, but with fewer juvenile birds. Breeding success among Atlantic brant also appears to have been adversely affected by harsh
spring weather in the eastern Canadian Arctic. Greater snow geese fared better
on their breeding grounds, and a fall flight similar to last year is expected.
LOOKING AHEAD
In 2007, improved habitat conditions on key breeding areas allowed
most duck species to build upon healthy population increases achieved in 2006,
producing what by all indications will be a large continental flight of
waterfowl this fall. While this is certainly cause for celebration among
waterfowl hunters, wetlands and other key waterfowl habitats remain under siege
in many areas of North America, especially in
the Prairie Pothole Region. Now more than ever, hunters and other
conservationists must work together to support programs and government policies
that conserve wetlands and associated upland nesting cover. Only by conserving
habitat can we ensure that waterfowl populations will be able to reach their
full potential when the breeding grounds are wet.