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bATURAL HISTORY
SURVEY

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STATE OF ILLINOIS

William G. Stratton, Governor

DEPARTMENT OF REGISTRATION AND EDUCATION
Vera M. Binks, Director

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A SPECTACULAR WATERFOWL MIGRATION
THROUGH CENTRAL NORTH AMERICA

Frank C. Bellrose

Biological Notes No. 36 2s =*""***
Printed by Authority of the State of Illinois

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NATURAL HISTORY
SURVEY DIVISION

Harlow B. Mills, Chief

Urbana, Illinois April, 1957

MAY ACE 7

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A SPECTACULAR WATERFOWL MIGRATION
THROUGH CENTRAL NORTH AMERICA

FRANK C. BELLROSE, Game Specialist, Natural History Survey Division

An exceedingly large and spectacular waterfowl
migration began on the Great Plains of Canada on
October 31, 1955, and moved southward in the United
States within the Mississippi Flyway on November 1, 2,
and 3. Veteran observers concurred that it was the
largest single movement of waterfowl since the Armi-
stice Day storm of 1940. Because of the magnitude of
this migration and because of the large number of
observers who happened to be in the field at the time,
the event afforded an unusual opportunity to assemble
and analyze the reports of a truly great movement of
waterfowl. Also, it afforded an opportunity to study the
effect of weather elements on waterfowl migration.

The compilation and analyses of the migration ‘re-
ports, which covered an area that extended from west-
central Canada to the Gulf of Mexico, provided infor-
mation on the routes followed by waterfowl in the
Mississippi Flyway, and the altitude, time, and speed
of migration under storm conditions. Fortunately, popu-
lation changes which resulted from the mass migration
in several areas of the flyway could be measured, for
some censuses were taken immediately before, some
during, immediately after the migration.
Waterfowl biologists throughout the Vississippi Flyway
had been taking periodic censuses, and November 1]

and some

was a date scheduled for one of these censuses.
ACKNOWLEDGMENTS

Many wildlife biologists, game agents, and refuge
managers in the Mississippi Flyway furnished informa-
tion on their observations of the spectacular waterfowl
migration that is the subject of this paper. Several
persons furnished material solicited from their col-
leagues: These were Arthur S. Hawkins of the United
States Fish and Wildlife Service; Forrest B. Lee of the
Minnesota Department of Conservation; Laurence R.
Jahn of the Wisconsin Conservation Department; and
William G. Leitch of Ducks Unlimited of Canada. Names
and addresses of persons who contributed information
on the spectacular flight are listed below.

George C. Arthur, Illinois Department of Conserva-
tion, Hamilton, Illinois.

Gus Artus,
Bowling Green, Missouri.

Irven Boeker, Upper Mississippi Wildlife and Fish
Refuge, La Crosse, Wisconsin:

Missouri Conservation Commission,

Homer L. Bradley, Long Lake National Wildlife
Refuge, Moffit, North Dakota.

J. R. Caldwell, Ducks Unlimited, Swift Current,
Saskatchewan, Canada.

Harry Canfield, Dallas City, Illinois.

J. C. Carlsen, Mud Lake National Wildlife Refuge,
Holt, Minnesota.

William D. Carter, United States Fish and Wildlife
Service, Winona, Vinnesota.

Mike Casey, Minnesota Department of Conserva-
tion, Forest Lake, Minnesota.

Robert E. Cleary, lowa Conservation Commission,
Independence, lowa.

Edward A. Davis, Upper Mississippi Wildlife and
Fish Refuge, Grafton, Illinois.

David Donaldson, Arkansas Game and Fish Com-
mission, Paragould, Arkansas.

George Freeman, Ducks Unlimited, Calgary,
Alberta, Canada.

William E. Green, Upper Mississippi Wildlife and
Fish Refuge, Winona, Minnesota.

Arthur S. Hawkins, United States Fish and Wildlife
Service, Minneapolis, Minnesota.

Lewis G. Helm, Missouri Conservation Commis-
sion, Columbia, Missouri.

Carl Hunter, Arkansas Game and Fish Commission,
Little Rock, Arkansas.

Laurence R. Jahn, Wisconsin Conservation Depart-
ment, Horicon, Wisconsin.

Harry A. Jensen, United States Fish and Wildlife
Service, Jamestown, North Dakota.

Forrest B. Lee, Minnesota Department of Con-
servation, St. Paul, Minnesota.

Roger A. Lehmann, Minnesota Department of Con-
servation, St. Paul, Minnesota.

William G. Leitch, Ducks Unlimited, Winnipeg,
Manitoba, Canada.

Harry T. Maltby, United States Fish and Wildlife
Service, Des Moines, Iowa.

Dale N. Martin, Indiana Department of Conserva-
tion, Columbia City, Indiana.

Frank R. Martin, Upper Souris National Wildlife
Refuge, Foxholm, North Dakota.

Harvey W. Miller, Nebraska Game, Forestation and
Parks Commission, Bassett, Nebraska.

Harland M. Morgan, United States Fish and Wildlife
Service, North Platte, Nebraska.

Ray Murdy, South Dakota Department of Game,
Fish, and Parks, Pierre, South Dakota.

Harvey K. Nelson, Shiawassee National Wildlife
Refuge, Saginaw, Michigan.

Maynard M. Nelson, Minnesota Department of Con-
servation, Fairmont, Minnesota.

Norman J. Ordal, Minnesota Department of Con-
servation, Fergus Falls, Minnesota.

E. V. Pierce, Upper Mississippi Wildlife and Fish
Refuge, Muscatine, Iowa.

Charles K. Rawls, Jr., Tennessee Game and Fish
Commission, Tiptonville, Tennessee.

George B. Saunders, United States Fish and Wild-
life Service, Atlanta, Georgia.

Lyle Schoonover, Mingo Swamp National Wildlife
Refuge, Puxico, Missouri.

James G. Sieh, Iowa Conservation Commission,
Okoboji, Iowa.

Parker Smith, Tennessee Game and Fish Commis-
sion, Paris, Tennessee,

M. E. Stempel, Iowa Conservation Commission,
Ottumwa, Iowa.

Milton Stenlund, Minnesota Department of Con-
servation, Ely, Minnesota.

R. TT. Sterling, Ducks
Saskatchewan, Canada.

Marshall L. Stinnett, United States Fish and Wild-
life Service, Peoria, [llinois.

Richard Vaught, Missouri Conservation Commis-
sion, Trimble, Missouri.

Peter Ward, Delta Waterfowl Research Station,
Delta, Manitoba, Canada.

Jerald J. Wilson, Snake Creek National Wildlife
Refuge, Riverdale, North Dakota.

Richard K. Yancey, Louisiana Wild Life and Fish-

eries Commission, Ferriday, Louisiana.

Unlimited, Wynyard,

Douglas M. A. Jones, Meteorologist with the
Illinois Water Survey, Urbana, aided in the interpreta-

tion of weather maps.

Several members of the staff of the Natural History
Survey Division were involved in making this paper
ready for publication. Dr. Thomas G. Scott and the
Editorial Committee of the Section of Wildlife Research
reviewed and improved the manuscript. James S. Ayars
edited it. William E. Clark made the photographs for the
frontispiece and fig. 1. Charles C. Harper and Forrest
D. Loomis prepared the maps and graphs. Loomis made
the silhouettes for the cover.

For all assistance that furthered the preparation
and publication of this report, the writer is most grate-

ful.

FLIGHTS PRIOR TO THE MASS MIGRATION

Prior to the mass waterfowl migration that began
on October 31, 1955, there had been a steady but un-
spectacular movement of waterfowl into the Mississippi
Flyway, fig. 1. Population levels for most of October,
1955, approximated those of October, 1954.

In the northern section of the flyway, there were
two pronounced movements of waterfowl previous to
October 31, 1955, one in the period October 23-24 and
one in the period October 28-30. Jerald J. Wilson re-
ported a constant movement of ducks, largely divers,
through the Turtle Mountains of North Dakota on
October 23 and 24. Four conservation officers in
Wisconsin observed flights of ducks, principally divers,
on the same 2 days. Large flights of diving ducks and
small flights of mallards (Anas platyrhynchos)* and
other dabbling ducks arrived in Illinois on October 23,
24, and 25.

William G. Leitch reported that large flights of
ducks departed on October 29 from the Libau Marshes
at the southern end of Lake Winnipeg, Manitoba. Also,
ducks were observed leaving the Delta Marsh, some 70
miles west of Libau, on October 30.

J. C. Carlsen reported that heavy movements of
gadwalls (Anas strepera) were noted at the Mud Lake
National Wildlife Refuge near Holt, Minnesota, on
October 28 and 29. On October 28, Jerald J. Wilson
observed a large movement of coots (Fulica americana)
from the Garrison Reservoir area of North Dakota. In
Wisconsin, seven observers reported the arrival of im-
portant flights of ducks, especially scaups (Aythya) and
other divers, on October 28, 29, and 30. Few, if any,
diving ducks arrived at this time in Illinois, but small
flights of mallards arrived along the Mississippi River.
between East Dubuque and Savanna, Illinois.

OBSERVATIONS ON MASS MIGRATION

Perhaps there was no sharp demarcation in time
between the duck flights just previous to October 31
and the initiation of the mass movement from the Great
Plains of Canada on October 31. There was, however,
a demarcation in magnitude: The earlier trickle of
southbound waterfowl developed into a flood of migrants
on October 31 and the 2 days following.

Canada.--For the area of Calgary, Alberta, George
Freeman reported to Ducks Unlimited of Canada that
blizzard conditions prevailed there on October 31 and
November 1, resulting in the exodus of most of the
waterfowl then present. After the storm, only a few

*This and other scientific names from Smith & Parmalee
(1955).

flocks of mallards were seen until November 10, when
_the last of the waterfowl disappeared from the area.
; For the Swift Current area, Saskatchewan, J. R.
Caldwell made the following comments in his report to
Ducks Unlimited of Canada: ‘Snow coupled with bliz-
zard conditions and very low temperatures caused a
-mass migration of waterfowl during a three day period,
October 31-November 2nd. The peak appeared to be
November lst from the personal observations and re-
ports of the Kee-men and hunters. The storm reached
its worst that day in southwest Saskatchewan with high
winds and drifting snow making visibility almost nil at
times. Birds moved steadily all day southward. By
Wednesday, November 2nd, all but a few of the larger
lakes in the southwest were closed over. The south
Saskatchewan River was full of ice and only a few
stragglers (possibly cripples) were seen in the Kin-
dersley area where lakes and sloughs had 3-4 inches of
ice on them by November 3rd.”

From Wynyard, Saskatchewan, R. T. Sterling re-
ported to Ducks Unlimited of Canada that the arrival of
low temperatures and snow during the period of October
31-November 2 caused the mass departure of all the
waterfowl then remaining in east-central Saskatchewan.
On October 31, several thousand gadwalls migrated
through Little Quill Lake. By November 2, the only
open water in the area consisted of a few holes on Big
Quill Lake, where there were small numbers of mallards.

According to Peter Ward, at the Delta Waterfowl
Research Station at the south end of Lake Manitoba in

Manitoba, the largest migration of waterfowl he had
ever witnessed occurred on November 1, 1955. The
flight lasted from 10:00 A.M. until dark, mallards
migrating throughout the day and lesser scaups (Aythya
affinis) from 4:00 P.M. onward., Flocks averaging 70 to
90 birds each crossed the lake shore line at quarter-
mile intervals on the average of one flock per minute.
Ward estimated that 215,000 ducks passed over.

Ward stated that the migration was very unusual in
that the bulk of the mallards passed through the Delta
area from the north in 1 day. Most of the waterfowl
which had been in the Delta Marsh joined the passing
flight. Up to November 1, there had been only the usual
drift through that area.

North Dakota.--Harry A. Jensen reported that a
mass migration of waterfowl occurred on November 1]
and 2 across the breadth of North Dakota from the Red
River valley to the Montana line. The flight was only
half as large on November 2 as on the preceding day. In
1 hour on November 1, 50 flocks were counted in mi-
gration near Dawson. Observers along the Missouri
River informed Jensen that it was the heaviest mi-
gration they had ever seen; about 85 per cent of the
flight was made up of mallards, the remainder being
lesser scaups. Approximately 100,000 mallards stopped
along the Missouri River from the Garrison Reservoir to
the South Dakota line, 25,000 mallards on Kunkel and
Horse Head lakes near Dawson, and 35,000 mallards on
Lake Ashtabula, north of Valley City. Jensen stated
that all flocks flew on a uniform course to the southeast.

Fig. l.--A steady but unspectacular movement of waterfowl into the Mississippi Flyway preceded the mass migration
that began on October 31, 1955,

At the Upper Souris National Wildlife Refuge,
Frank R. Martin saw large numbers of mallards and
scaups passing down the Souris River valley throughout
the day of November 1. He estimated that, at a point
east of Foxholm, 1,000 ducks per hour, in flocks vary-
ing from 25 to 100 birds each, were passing through a
half-mile gap in the valley. East of the valley, water-
fowl were present in even greater numbers, but they
were more widely dispersed. The flocks flew at heights
of 75 to 100 yards or lower — so low that some of the
ducks were shot down by hunters.

Homer L. Bradley, at the Long Lake National Wild-
life Refuge near Moffit, reported that throughout the
daylight hours of November 1 the air was full of ducks
in any direction that one might look. The mass move-
ment was similar to one which he had observed on
November 13, 1954, but the 1955 flight was larger. All
flocks, most of which were composed of mallards, were
flying south-southeast; few, if any, flocks stopped in
the area on their way through.

South Dakota.--In South Dakota, the peak of the
flight occurred on November 1. On that day, Ray Murdy
was aviating up the Missouri River from Fort Thompson
to the North Dakota line. Murdy reported the following:
“Throughout the whole flight we saw indications of a
large-scale, daytime mallard migration. As we were fly-
ing north we were continually meeting flocks of mal-
lards following the river south. This is the only time
we have seen such a movement on the river during the
three years we have made the survey. Also, for the first
time we saw numerous, scattered flocks of mallards
resting on open water where we have never seen mal-
lards before. We had the impression that these were
new arrivals that were unfamiliar with the river and had
landed to rest before they had reached one of the nu-
merous concentration areas.”

Upon returning at night to his home at Webster in
northeast South Dakota, Murdy heard from local hunters
that there had been a very heavy movement of ducks
through that area all day (November 1). The ducks
passed through without stopping, and, on November 2,
Murdy found that even the waterfowl which had been in
the Waubay Hills area the preceding day had departed
during the night.

Driving through eastern South Dakota on November
1, James G. Sieh did not notice migrating waterfowl un-
til about 2 P.M., when he observed several flocks fly-
ing southward above the prairie hills near Clear Lake,
about 10 miles west of the Minnesota line.

Nebraska.--In the Bassett area of north-central
Nebraska, Harvey W. Miller observed only a minor duck
flight on November 1 and 2. To the east, on the Missouri
River, excellent shooting occurred on November 1, 2, 3,
and 4. Miller reported that neither the game managers in

6

the Lincoln area, in the east, nor those in the Alliance
area, in the west, recorded large movements of water-
fowl at that time, but that the game manager for the
North Platte area in central Nebraska recorded large
flights on the nights of November 1 and 2.

The large flight of waterfowl into the North Platte
area was observed also by Harland M. Morgan. He re-
ported that, during the night of November 1, -40,000
ducks and 500 Canada geese (Branta canadensis) ar-
rived at the Sutherland Reservoir and that more arrived
during the ensuing day, November 2. At the North
Platte Reservoir, the number of ducks increased from
2,500 to 15,000. The migration was made up largely of
mallards, but with considerable numbers of lesser
scaups and smaller numbers of all other ducks indigen-
ous to the area.

Minnesota.--At the Mud Lake National Wildlife
Refuge in northwest Minnesota, J. C. Carlsen observed
flock after flock of ducks passing through on November
1. The stream of ducks, most of which were mallards
interspersed with scattered flocks of divers, consisted
of groups of about 25 to 200 birds. Between October 28
and November 2, Carlsen estimated that over 100,000
ducks. passed over the refuge. There was very little
evidence of migration on November 2.

On November 1, Forrest B. Lee observed great
numbers of ducks while he was making an aerial census
of waterfowl on east and west transects through the
west-central part of the state; the southernmost transect
passed a few miles north of Fergus Falls. Lee reported
that although he observed some flocks of migrating
ducks during the morning, the flight did not reach
spectacular proportions until afternoon. From 1:00 to
3:00 P.M., flocks of waterfowl, almost all mallards,
were tallied from the airplane at the rate of 75 flocks |
per hour.

Lee observed that most of the flocks were flying to
the southeast but that some were migrating due south.
Many flocks were flying as low as 100-150 feet above
the ground, and, although most were higher, 700-800
feet appeared to be the highest altitude for those visi-
ble. None of the passing waterfowl showed the slight-
est interest in stopping at any of the innumerable lakes
over which they flew.

Norman J. Ordal reported that fisheries personnel
of the Minnesota Department of Conservation counted
139 flocks while driving 18 miles from Perham to
Detroit Lakes on November 1. The flight was first
noticed in that area at about 11:00 A.M.

In northeastern Minnesota, biologist Milton Stenlund
noted no indication of a major flight on November 1 or
2 in the Superior National Forest area. Manifestly, the
principal flight of waterfowl was farther to the west
at that time.

Maynard M. Nelson first noticed the mass flight in
the south-central part of Minnesota at 4:30 P.M. on
November 1. Between 5:00 and 6:00 P.M., at Pierce
Lake in Martin County, he counted 41 flocks, which
contained an estimated 4,125 ducks. None of these
flocks stopped, but, that night, a multitude of ducks
descended on Martin County lakes; large concentrations
of ducks were observed by Nelson in that area the fol-
lowing morning.

At Talcott Lake, about 50 miles to the northwest
of Pierce Lake, Roger A. Lehmann at 4:15 P.M. no-
ticed the first of many flocks of mallards flying from
the north on November 1. From that time until it was
too dark to see, he observed a continuous flight to the
lake. The flocks of mallards varied from 50 to 300 birds
each.

The mass flight was still in progress in some
areas of Minnesota on November 2. A short distance
north of St. Paul, Mike Casey saw flocks of migrating
waterfowl from daylight to 10:30 A.M. Mallards predomi-
nated in the flight, which included smaller numbers of
scaups, cing-necked ducks (Aythya collaris), redheads
(Aythya americana), canvasbacks (Aythya valisineria),
and Canada geese. Flocks varied in size from 10 to
several hundred birds each. Although large, high-flying
flocks continued on in flight, many small, low-flying
ones dropped into the Carlos Avery Refuge. The ducks
were flying at altitudes that varied from a few hundred
feet to heights at which they were barely discernible
to observers on the ground.

Mississippi River.--On the Upper Mississippi Wild-
life and Fish Refuge south of Winona, Minnesota,
William D. [Pete | Carter watched the departure of
25,000 ducks between 7:30 and 8:30 A.M. on November
2. During that hour, flocks of 50 to 150 ducks were tak-
ing flight toward the south at about 5-minute intervals,
until only 5,000 remained. Farther down the river during
the rest of the day, Carter observed a steady flight of

-ducks southward; none of these ducks appeared to stop.

On the following day he observed only a few flocks, all
of them flying high and moving southward.

About 175 miles south of Winona on the Mississippi
River, near Clinton, Iowa, Dr. William E. Green and
Irven Boeker were aviating north at an altitude of 1,200
feet on November 2. Suddenly, at 9:00 A.M., they were
surrounded by a heavy flight of ducks heading south-
east. As far as they could see on each side, as well as
above and below the plane, ducks filled the air. For an
hour, Green and Boeker, aviating on a northwesterly
course across country to Prairie du Chien, Wisconsin,
watched the flight of waterfowl continue. These water-
fowl appeared to be taking a short-cut across the big
eastward bend of the Mississippi River in northwestern
Illinois.

About 70 miles southwest of Clinton, at the Louisa
National Wildlife Refuge, adjacent to the Mississippi
River near Wapello, Iowa, E. V. Pierce saw the mass
duck migration on November 2. Following is his vivid
description of it: ‘‘Starting at about daylight and last-
ing without any apparent let-up until about an hour after
noon, there took place a migration of ducks, mostly
mallards, that simply defies description. If an accurate
description could be written, anyone not having seen
the migration could not possibly believe or imagine
what went on. All the duck hunters who were fortunate
enough to be out in the Odessa bottoms at Louisa that
day agree that they witnessed the largest and most con-
centrated flight of ducks they had ever seen in their
lives in any single day. There was a strong west-
northwest wind mixed with light rain, sleet, and snow.
Visibility was extremely limited, but, from within gun
range to as far and as high as one could see, the air
was literally full of ducks. For about an hour, between
8 and 9, the flight was hardly divided into flocks, but
rather appeared to be just one solid drove of birds. As
nearly as anyone could tell, this flight came right down
the Mississippi and also, in probably greater numbers,
from the west and northwest. The great majority of
these birds flew right on through this neighborhood, but
by evening Louisa Refuge held at least 150,000 mal-
lards.”’

Forty miles farther downstream, on November 2, at
Dallas City, Illinois, Harry Canfield noted rafts of mal-
lards scattered over the river surface at dawn where
none had been the evening before. Other flocks of
mallards were winging overhead, and a steady flight
continued until 11:00 A.M.; at that time a snow shower
started, after which the magnitude of the flight sharply
diminished. Although mallards made up the bulk of the
flight, there were numerous flocks of lesser scaups,
ring-necked ducks, and canvasbacks, along with a few
flocks of gadwalls and widgeons or baldpates (Mareca
americana).

Some 30 miles southeast of Dallas City at Col-
chester, Illinois, hunters saw many flocks of mallards
passing southward in the dim light of early dawn on
November 2.

From a bluff overlooking the Mississippi River
near Hannibal, Gus Artus witnessed on
November 2 the greatest waterfowl migration he had
ever seen. From dawn through the morning, myriads of
flocks of southbound ducks were in sight for several
miles to the east, over the flat valley lands on the

Missouri,

Illinois side of the Mississippi River. His view to the
west was limited by hills to a mile or so, but, as far as
he could see in that direction, there also were flocks of
migrating ducks. By early afternoon, the magnitude of

the flight had diminished.

~~

Still farther south in the Mississippi River valley,
at Batchtown, Illinois, was Edward A. Davis, who re-
ported that at daybreak on November 2 thousands of
newly arrived mallards were resting on the river. For
the remainder of the day, flocks filled the air at alti-
tudes ranging from several hundred to 2,000 feet. As
the flocks moved southward, only a small fraction of the
flying ducks stopped at nearby refuges. Davis esti-
mated that he saw 600,000 to 900,000 ducks, the bulk
of which were mallards; with the mallards were smaller
numbers of lesser scaups, ring-necked ducks, canvas-
backs, pintails (Anas acuta), gadwalls, and widgeons.
Unusually large numbers of massed groups of 2,000 or
more ducks were in evidence. Reports of hunters and
farmers who were near the mouth of the Illinois River
on November 2 indicated that ducks migrated in a belt
approximately 40 miles wide across Jersey County,
Illinois.

Along the Mississippi River in extreme southern
Illinois, George C. Arthur first noticed the mass mi-
gration at 10:00 A.M. on November 2. The ducks, most
of them mallards, were flying between the river channel
and the valley bluff; the migration continued at least
until dark.

At this point the mass flight extended 60 or 70
miles to the west, at least as far as Lake Wappapello,
Missouri. At Mingo Swamp National Wildlife Refuge,
adjacent to Lake Wappapello, Lyle Schoonover observed
a heavy flight through the area on November 2 and 3.
About 50,000 mallards stopped at the refuge, from which
there was a gradual departure during the next 10 days.

In driving the 40 miles from Puxico east to Sikes-
ton, Missouri, on the morning of November 2, Schoonover
observed scattered flocks of southbound ducks at alti-
tudes of 400 to 1,000 feet. On the same day, Richard
Vaught in driving southwest 50 miles from Cape
Girardeau to Puxico observed a continual procession of
migrating ducks, most of them mallards.

Wisconsin.--There
sections of Wisconsin, of unusually large flights of
waterfowl between October 30 and November 5.
Laurence R. Jahn extracted comments from the reports
submitted by field personnel of the Wisconsin Con-

were 22 reports, from many

servation Department. Specific dates relating to the
flights were not given in all cases, but two observers
reported movements for October 30, two for October 31,
one for November 1, seven for November 2, and four for
November 3.

Some of the reports regarding waterfowl movements
in Wisconsin at that time were as follows: In Burnett
County in the northwestern part of the state, a very
heavy mallard flight started the evening of October 31;
it was still heavier on November 1] and 2. In addition,
75 whistling swans (Olor columbianus) were seen flying

8

south over the Crex Meadows on November 2; other
swans were reported in migration over Winnebago
County on November 2. On November 3, at Lake Poygan,
in the same county, 20-30 flocks of swans, numbering
30-75 birds per flock, were observed flying southeast.
Peak numbers of ducks were reported on November 2.

Several reports were from the Wisconsin River area
in Iowa and Dane counties. One field man in that area
reported a good flight of ducks on November 2, with 94
flocks in migration near Arena. Another observer in the
same area stated that there were heavy flights of mal-
lards and diving ducks on October 30 and November 2.
He estimated that 1,000 ducks passed over in 3% hours
on October 30 and 4,000 in 4% hours on November 2.
Flocks were large, flying high, and heading east, south-
east, south, and southwest. The flight was light there
on November 3.

A large duck flight was reported on November 2 in
Jefferson County, in the southeastern part of the state.
In Lafayette County, in the southwestern corner of the
state, 10 flocks of geese and many ducks were noted
the same day.

Michigan.--Harvey K. Nelson, who for several years
had observed waterfowl movements through the Saginaw
River valley and Saginaw Bay area of Michigan, in 1955
assisted the Michigan Department of Conservation in

periodic waterfowl censuses of that area.
Nelson reported that local hunters saw large

flights of ducks, primarily redheads, canvasbacks, and
mallards, moving into and through Saginaw Bay on the
afternoon of October 31. During an airplane census
flight on November 1, he observed small groups of red-
heads, canvasbacks, and scaups flying over Saginaw
Bay from the northwest to the southeast, but, at that
time, no mass ‘movement was in evidence. However, on
November 2, hunters reported mass flights of ducks and
excellent hunting. Migration was further evinced by
observation of increased numbers. of mallards, black
ducks (Anas rubripes), redheads, and scaups in the
Saginaw River marshes on November 2 and 3. A major
exodus of widgeons took place on those dates.
lowa.--The flight of waterfowl through [owa on
November 2, according to James G. Sieh, ran into mil-
lions of birds. The migration first appeared in the lake
region of the northwestern part of the state late in the
afternoon of November 1. By daylight the following
morning, migration was well underway. Throughout the
day, Sieh saw large flocks of mallards pass nonstop
over Big Spirit Lake in a southeasterly direction. Other
flocks of mallards, which had alighted on Big Spirit
Lake during the afternoon or night before, took flight
periodically throughout the morning, as they, too, joined
the migrating stream of ducks. Only a few flocks of
diving ducks departed during the morning, but, late in

the afternoon of November 2, they commenced to leave
Big Spirit Lake, where they had rested during the day-
light hours. From 4:30 P.M. until dark, hundreds of
flocks of lesser scaups and ring-necked ducks departed
on a front only 1,000 yards wide from west to east.

Harry T. Maltby reported that, on November 2,
10,000 mallards and 3,500 canvasbacks and redheads
plus 2,000 miscellaneous ducks were found resting on
the Missouri River between Sioux City, Iowa, and the
Missouri line, apparently having arrived the night of
November 1-2. Maltby provided the following figures for
ducks which alighted on November 2 at lakes in the
northwestern and western parts of the state: Round
Lake, 3,000 mallards; Storm Lake, 5,000 mallards;
Rush Lake, 2,000 mallards; Silver Lake, 750 mallards;
and Blackhawk Lake, 3,000 mallards.

Robert E. Cleary, on the banks of the Wapsipinicon
River, near Independence, at daybreak on November 2,
noted ducks flying to the southeast down the valley in
a steady stream; the flight continued until late after-
noon. Between 6:30 and 8:30 A.M.,
species, even ruddy ducks (Oxyura jamaicensis), oc-
curred in the flight. After 8:30 A.M., mallards pre-
dominated in the flight; they were followed in order of

divers of all

numbers by pintails, green-winged teals (Anas caro-
linensis), shovelers (Spatula clypeata), gadwalls, and
widgeons. For the most part, flocks averaged about 100
birds each, all flying at altitudes of several hundred
feet.

Near Eddyville on the Des Moines River, M. E.
Stempel observed 66 flocks, aggregating 7,000 ducks,
between 6:30 and 10:00 A.M. A flock of 10 to 500 ducks
passed by every 3 minutes during this period. After-
wards the flight diminished and an increasing overcast
reduced visibility; only three large flocks were ob-
served from 10:00 A.M. to 12:00 noon. Between 6:30
and 7:40 A.M., about half of the flocks consisted of
divers and the other half of mallards. Later, practically
all the flocks were made up of mallards. Most of these
' ducks were flying straight south toward the Chariton
River valley.

IHinois.--In Illinois, the prelude to the 1955 mass
migration of waterfowl occurred on November 1, when
ducks appeared in the middle reach of the Mississippi
River. We first became aware of this movement at 10:00
A.M. while aviating up the Mississippi River from
Grafton toward Quincy. From the plane, we saw 20
flocks of mallards flying south at an altitude of 500
feet. Edward A. Davis told us that, on November 1,
2,000 flocks passed down the Mississippi River at
Batchtown, Illinois, most of them at altitudes over
1,000 feet. Most of the flocks, made up of mallards,
numbered 25 to 50 birds each, but some contained as
‘many as 100 to 200 birds.

By the morning of November 2, it was evident that
a tremendous migration of waterfowl was underway in
the state. At daybreak, many observers saw a steady
stream of ducks, most of them mallards, arriving in the
Illinois River valley from the north, northwest, and,
occasionally, from the southwest or east. Up and down
the valley, throughout the day, the flight continued.
Hunters had a ‘“‘field day’? as newly arrived mallards
decoyed to almost any kind of call.

At 8:00 A.M., we saw large flocks of mallards
wheeling into the [llinois River valley above Havana.
Within the next hour, 40 flocks numbering 50 to 100
mallards each were noted flying toward the valley from
the east. Twenty miles below Havana, a continuous,
almost unbroken stream of mallards passed down the
valley throughout the day. Most of the flocks were
following the valley, which angles in a southwest
direction, but some were leaving the valley to fly
directly south over the prairie farm lands. Although the
bulk of the ducks appeared to be passing through non-
stop, flocks now and then became detached from the
passing throng to alight on the lakes and marshes of
the Illinois River valley. By nightfall, local duck popu-
lations had tripled or quadrupled. The populations were
at a peak for only a short time, however. Hither many of
the recently arrived ducks remained for only a few hours
of rest before continuing south, or many of the ducks
which had been present at the time the mass flight
reached the valley resumed their migration during the
night. For example, at Crane Lake, near Bath, the duck
population dropped from 120,000 the evening of Novem-
ber 2 to 85,000 by the following morning.

Ducks migrated into the upper Illinois River valley
all through November 2. At 2:00 P.M., east of Morris,
Marshall L. Stinnett noticed 25,000 mallards dropping
into the valley from the northwest. As he proceeded
west by car to Bureau, on a highway paralleling the riv-
er valley, he observed flocks of mallards continually ar-
riving from the northwest. South of Bureau, the mi-
gration of waterfowl was still greater, and, late in the
afternoon, Stinnett estimated that 150,000 ducks
dropped into the bottomland lakes of the Illinois River
between Bureau and Henry.

Indiana.--Dale N. Martin, making aerial flights over

Indiana on October 31 and November 1 and 2, saw no
indication of a mass waterfowl migration until early on
the morning of November 2. Throughout the rest of the
day, he observed ducks arriving at the Willow Slough
Game Preserve from the northwest and north. The
principal migrants were mallards, but considerable num-
bers of black ducks, gadwalls, green-winged teals, red-
heads, canvasbacks, scaups, and ring-necked ducks
also arrived. Coots departed from Willow Slough the
night of November 3.

Missouri.--Lewis G. Helm provided the following
excellent review of the 1955 mass waterfowl flight in
Missouri: ‘‘The impressive duck flight that began on the
night of November 1] in Missouri and continued through-
out the day of November 2 was the greatest flight of
ducks seen by many observers in the state. To many
people it rivaled the November 11, 1940, flight in both
speed and extent, and the number of ducks involved is
reported to be even greater than the 1940 flight.

‘‘There was some indication that the flight into
Missouri started on the last day of October, especially
in the southeast section of the state. An aerial count of
waterfowl was made over the northwest portion of the
state on October 31, but only relatively small numbers of
ducks were counted on the concentration areas. Squaw
Creek Refuge contained 36,000 mallards; Swan Lake,
10,000; while the remainder of north Missouri was esti-
mated to have but 35,000 mallards. Peak numbers of
Canada geese had already been reached in north
Missouri; approximately 50,000 geese had left the state
by October 31.

“‘November 1 was a mild fall day in north-central
Missouri, with only scattered clouds and mild tempera-
tures, which climbed into the high 60’s. By evening it
was apparent that a change of weather was due. By the
morning of the second there was snow and sleet on the
ground, and low clouds were racing across the sky from
the north and west. Ducks, particularly mallards and
green-winged teal, were observed flying just under the
cloud ceiling at about 100 feet altitude. Many birds
were seen on open water areas of refuges and farm
ponds throughout the northern part of the state, and by
afternoon observers in all parts of the state reported a
heavy movement of ducks. The main lines of flight were
along the larger rivers, such as the Mississippi,
Missouri, Chariton, and North Grand rivers; however,
ducks were seen from points located on uplands in most
sections of the state and throughout the Ozarks. Ap-
parently what took place was a broad band of migration
from one edge of the state to the other, with the most
birds flying along the major river systems.

“The mallard was the main species involved in the
flight, but other species were prominent too. The green-
winged teal appeared in good numbers throughout the
state, with the greatest concentration recorded in the
central regions. Lesser scaup moved through the state
rapidly and only a relatively few thousand stayed for
more than 2 or 3 days. Of an estimated 50,000 scaups
moving into and through the state on November 2, only
4,000 could be accounted for on November 5. Smaller
numbers of other divers, notably ring-necked. ducks,
moved through the state during and after November 2.

““Comparing the counts made by aerial inventory on
October 31 with ground checks during and immediately

10

after the large flight of ducks, at least 750,000 mal-
lards must have been involved in the flight into and
through Missouri.

“*An interesting facet of the November 2 flight is
the fact that, apart from the very eastern counties,
observers in Kansas noted no marked migration of
either ducks or geese.”

In the Sumner-Brunswick area of Missouri, flocks
of low-flying mallards were ‘‘pouring over’’ at daybreak
on November 2. Many flocks were dropping out of the
passing stream of waterfowl to alight on ponds, creeks,
and other small bodies of water which normally are
seldom frequented during the fall. The flight continued
most of the day, with the ducks flying south and south-
east. Near Paris, the flight was entirely toward the
southeast.

Tennessee.--Concerning the 1955 mass migration
in Tennessee, Parker Smith wrote as follows: ‘*There
is no question but that a huge influx of birds occurred
on November 2 and 3. Mallards, black ducks, ring-
necked ducks, and wood ducks [ Aix sponsa_} were the
main species on Kentucky Lake, and mallards, gad-
walls, baldpates, pintails, and ring-necked ducks were
the major species on Reelfoot Lake.”’

Charles K. Rawls, at Reelfoot Lake, reported that
from 7:30 A.M. until dark on November 2 he saw 15-25
flocks containing 50-100 mallards each passing over at
any given moment. Many flocks streaking southward on
the heels of a strong north wind attempted to hook into
the wind and alight, but were blown backward. By the
morning of November 3 the flight was smaller and by
noon it was over. This was the largest flight of ducks
observed at Reelfoot Lake in the past 10 years.

Arkansas.--Carl Hunter reported that there was no
evidence of a mass duck flight in Arkansas on Novem-
ber 1. On November 2, however, radio reports were re-
ceived from wardens to the effect that large numbers of
ducks, mostly mallards, were arriving. This flight was
indicated as the largest recorded single movement of
waterfowl into the state. The ducks appeared to arrive
over the entire eastern part of the state at about the
same time.

On November 3, while aviating over northeastern
Arkansas, Hunter and David Donaldson saw numerous
strings of ducks flying south, some at altitudes as high
as 1,500 feet. Near Jonesboro, they watched hundreds
of ducks scale down from 1,500 feet to join rafts of
ducks already resting on the Claypool Reservoir.

Louisiana.--Richard K. Yancey observed mass
flights of mallards, gadwalls, green-winged teals, pin-
tails, and scaups arriving in Louisiana on November 2
and 3. He reported that smaller, but the first important,
flights of ring-necked ducks, canvasbacks, redheads,
and ruddy ducks also arrived at that time. Increased

numbers of shovelers, baldpates, and coots swelled
_ populations already present.

Yancey made the following statement: ‘‘Although
the waterfowl flight [of November 2 and 3_] descended
to a degree like a blanket over Louisiana, it appeared
to develop its greatest magnitude along the Mississippi
and Red rivers. For the most part, the flocks were

}
r

traveling in a southerly direction, and the flocks ob-
served were flying principally at altitudes of 300-400
feet. . . . During the course of this early November
waterfowl inventory [{ aerial ], migrant flocks could be
seen at almost any point over the rice fields of south-

‘Reg

western Louisiana, or in the vicinity of any major body
of water in north and central Louisiana.”’

Dr. George B. Saunders reported that the flight ar-
rived on the Louisiana coast at the Lacassine National

Wildlife Refuge on November 3.

POPULATION CHANGES AS A RESULT OF FLIGHT

The effect of the mass migration of 1955 on water-

_ fowl populations in the Mississippi Flyway was pro-
nounced. Waterfowl censuses made in five states, im-
mediately prior to and after this spectacular flight,
show more than a three-fold increase in the duck popu-
lations of the flyway, table 1. Among the 12 areas for

which there are data, the relative increases were simi-
lar in all but two areas: Martin County, Minnesota, and
Swan Lake National Wildlife Refuge, Missouri, both of
which registered a 12-fold increase.

Information on the change in species composition
resulting from the mass migration is available for a
Minnesota area, the lower Illinois River valley, and the
state of Louisiana, tables 2, 3, and 4. In the Minnesota
area, table 2, a large ingress of mallards and lesser
scaups occurred along with an egress of gadwalls and
pintails. In the Illinois River valley, table 3, a sizable
ingress occurred in mallards, black ducks, lesser
scaups, and canvasbacks concomitant with a sizable
egress in widgeons, green-winged teals, shovelers,
ring-necked ducks, and coots.

All species of waterfowl but the blue-winged teal
(Anas discors) increased in numbers in Louisiana,
table 4. The influx of migrants was especially pro-
nounced for the mallard, gadwall, green-winged teal,
redhead,
scaup.

The chronology of waterfowl migration in the
Illinois River valley in 1954 and 1955 is shown in fig.
2. The population trend for October, 1955, was similar
to that for October of the year before. By November 1,
1955, the number present in the Illinois River valley

canvasback, ring-necked duck, and lesser

Table 1.--The increase in waterfowl populations in areas of the Mississippi Flyway which were censused im-
mediately before and after the spectacular waterfowl flight of late October and early November, 1955.

Preflight Postflight
State Observer area Population* Population*
South Dakota Ray Murdy Missouri River 105,543 323,770
Minnesota Maynard M. Nelson Martin County 1,364 16,370
Illinois Edward A. Davis Calhoun Refuge 53,500 195,000
. Batchtown Refuge 38,000 82,000
Frank C. Bellrose Lower Illinois River valley 358,575 814,855
Indiana Dale N. Martin Jasper-Pulaski Refuge 1,100 5,500
Kankakee Refuge 12,000 38,000
Willow Slough Game Preserve 24,000 40,000
Missouri Lewis G. Helm Squaw Creek Refuge 36,000 160,000
Swan Lake Refuge 10,000 125,000
Other northern areas 35,000 125,000
Louisiana Richard K. Yancey State-wide 477,000 1,481,000
Total 1,152,082 3,406,495 _

*Figures are based on waterfowl censuses made on the following dates: South Dakota, October 26-27 and November 1;
Minnesota, November 1 and 2; Illinois, November 1 and 3; Indiana, October 31 and November 3; Missouri, October 31 and

November 5; Louisiana, October 31 and November 4.

ll

Table 2.--The change in waterfowl populations in
Martin County, Minnesota, as a result of migration on
November 1, 1955.*

Number of Ducks Observed

Species October 31- Noeee tS
November 1

Mallard ily 13,495
Gadwall 28 0
Pintail 15 0
Green-winged teal 2 2
Ring-necked duck 20 30
Canvasback 6 20
Lesser scaup 2 2,725

Total 15225 16,272

*Data provided by Maynard M. Nelson, Minnesota Depart-
ment of Conservation.

Table 3.--The change in waterfowl populations in
the Illinois River valley between Peoria and Meredosia,
Illinois, as a result of migration on November 2, 1955.

Number of Ducks Observed

BBs November 1 November 3
Mallard 281,975 739,860
Black duck 2,840 7,500
Gadwall 1,805 1,260
Widgeon 5,140 2,765
Green-winged teal 10,275 2,825
Blue-winged teal 100 0
Shoveler 390 45
Pintail 33,450 38,000
Redhead 250 40
Canvasback 910 1,540
Lesser scaup 2,850 9,600
Ring-necked duck 18,080 8,390
Ruddy duck 510 130

Total 358,575 811,950
Coot 87,925 63,200

had risen to 663,000, about the same number as were
present on November 2, 1954. By November 3, 1955, the
calculated duck population in the area had risen to
1,487,000, whereas on November 2-3, 1954 (2-day
census), it was about 693,000. Not until November 14
did the 1954 duck population rise to a peak comparable
to that found on November 3, 1955. It thus appears that
weather conditions prevalent on October 31 and Novem-
ber 1 and 2, were responsible for accelerating the mi-
gration by almost 2 weeks in 1955.

12

Table 4.--The change in waterfowl populations in
Louisiana as a result of migration on November 2 and

3, 1955.*

Number of Ducks Observed

Yeas: October 31 November 4
Mallard 5,000 330,000
Black duck 0 7,000
Gadwall 15,000 225,000
Widgeon 75,000 125,000
Green-winged teal 30,000 220,000
Blue-winged teal 200,000 10,000
Shoveler 30,000 60,000
Pintail 120,000 250,000
Redhead 0 2,000
Canvasback 0 12,000
Ring-necked duck 1,000 20,000
Lesser scaup 1,000 220,000

Total 477,000 1,481,000
Coot 175,000 340,000

*Data provided by Richard K. Yancey, Louisiana Wild
Life and Fisheries Commission.

DAILY WEATHER CONDITIONS

The following review of weather conditions leading
up to and during the mass migration of waterfowl on
October 31 and November 1-3, 1955, was made from
weather maps of the United States Weather Bureau and
the Meteorological Division of the Canadian Department ~
of Transport. These maps, temperature records, and ©
comments on weather conditions reported by field men
of Ducks Unlimited of Canada provided useful means
for analyzing the relationship between weather con-
ditions and the mass migration.

October 29.--The weather map for 6:30 P.M.,
C.S.T., showed a fairly deep low pressure area centered
over northeastern Wisconsin. From the low, an east-
ward-moving cold front extended in a semicircle through
western New York, central South Carolina, and north-
central Florida. Also from the low, a westward-moving
warm front extended northward across James Bay. High
pressure areas occurred over Churchill, Manitoba, and
the District of Mackenzie.

October 30.--By 6:30 P.M., C.S.T., the cold front
had become stationary and extended from Quebec east-
ward to the coast of New Jersey; the warm front had
moved from its October 29 position a short distance
northwest to Hudson Bay. The low pressure area that

had been

centered over northeastern Wisconsin on

1,750

1,500

1,250

1,000

750

500

NUMBER OF WATERFOWL, THOUSANDS

250

15 20 25
OCTOBER

30

4 9 14 19
NOVEMBER

Fig. 2.—Waterfowl populations in the Illinois River valley from mid-October to mid-November, 1954 and 1955, as de-
termined by aerial surveys. The survey on November 3, 1955, covered only half of the waterfowl habitat in the Illinois River
valley; the figure for the entire area was calculated from this sample.

October 29 remained there, while another low pressure
area had developed in southeastern Alberta and south-
western Saskatchewan. A ridge of high pressure ex-
tended from Alaska into the District of Mackenzie.
October 31.--The weather map for 6:30 A.M.,
C.S.T., fig. 3, showed the low pressure area that had
been over Wisconsin had shifted northward to the region
west of James Bay and had filled slightly; the low over
Alberta and Saskatchewan had remained stationary; and
a new low had developed over central South Dakota. A
high pressure area had centered over northern Yukon. A
synopsis issued by the Canadian Meteorological office
stated the following: ‘‘The first storm of the winter is
centered over eastern Alberta this morning [ October
31_] and will move southeastward through Montana and
_ North Dakota during the day. Snow has fallen over most

in Alberta and the
Peace River block. Strong winds have caused blowing
snow in Alberta and Saskatchewan. As the system

regions, with heaviest amounts

moves southward colder air will gradually drop tem-
peratures in all regions.”

November 1.--By 6:30 A.M., C.S.T., fig. 4, the low
pressure area west of James Bay had deepened and
moved northwest to the vicinity of Churchill, Manitoba.
The strong high remained centered over northern Yukon.
A pronounced cold front of Continental Arctic air was
moving southeastward across the Dakotas. A weak cold
front of Maritime and Continental Polar air was moving
that included
Michigan and Illinois. The following weather synopsis

eastward across a number of states

was issued by the Canadian Meteorological office:
“Snow is still falling over the prairies this morning.

13

—4— COLD FRONT °

_a WARM FRONT
4 OCCLUDED FRONT
--— ISOBARS
WIND DIRECTION AND
VELOCITY

120

Fig. 3.--Weather conditions prevailing at 6:30 A.M., C.S.T., October 31, 1955; shown are pressure areas, isobars, fronts,
and wind directions and velocities as reported by the United States Weather Bureau.

14

LEGEND

COLD FRONT \
WARM FRONT ee
OCCLUDED FRONTS
ISOBARS

WIND DIRECTION AND
VELOCITY

120

Fig. 4.--Weather conditions prevailing at 6:30 A.M., C.S.T., November 1, 1955; shown are pressure areas, isobars, fronts,
and wind directions and velocities as reported by the United States Weather Bureau.

\ ri
COLD FRONT ‘ 8

WARM FRONT

OCCLUDED FRONT
ISOBARS

WIND DIRECTION AND
VELOCITY

120

Fig. 5.--Weather conditions prevailing at 6:30 A.M., C.S.T., November 2, 1955; shown are pressure areas, isobars, fronts,
and wind directions and velocities as reported by the United States Weather Bureau.

16

7
LEGEND

COLD FRONT

WARM FRONT
OCCLUDED FRONT
|SOBARS

WIND DIRECTION AND
VELOCITY

120

Fig. 6.--Weather conditions prevailing at 6:30 A.M., C.S.T., November 3, 1955; shown are pressure areas, isobars, fronts,
and wind directions and velocities as reported by the United States Weather Bureau.

17

However, the heaviest snow fall appears over. The
snow is expected to end over Alberta on Wednesday
[ November 2 ], but continue over the remaining re-
gions.’’ Snow was falling over North Dakota and north-
ern Minnesota, also. Winds were under the influence of
the deep low centered near Churchill, Manitoba.

November 2.--While the high pressure area remained
centered over northern Yukon, an extension of this area
moved south along the Continental Divide and, within
this extension, a separate center was beginning to form
over western Wyoming, fig. 5. The low pressure area in
the vicinity of Churchill remained virtually stationary
but deepened further. The weather in the north con-
tinued to be under the influence of this deep low. Snow
continued to fall over most of Saskatchewan, Manitoba,
and Ontario.

A secondary low pressure area, which had been de-
veloping over Arizona, New Mexico, and neighboring
states on November 1, began to deepen on November 2
and move rapidly northeastward along the cold front; it
reached southern Illinois by 12:30 P.M. and central
Illinois by 6:30 P.M. This low brought overcast con-
ditions, scattered snow showers, and strong winds to
the Middle West. In the Mississippi Flyway, the cold
front extended in a southwest-northeast direction from
southern Missouri to north-central Ohio.

November 3.--By November 3, the weather in the
southern part of the Mississippi Flyway was under the
influence of a strong high pressure area centered over
northeast Texas, fig. 6. With the clockwise flow of air
around the high, winds from the northwest occurred in
Iowa, Illinois, Missouri, Arkansas, and Mississippi.
Wind velocities in these states generally ranged from 15
to 20 miles per hour.

The weather in the northern part of the flyway was
under the combined influence of the low that had been
over central Illinois on November 2, and that had moved
to the vicinity of Georgian Bay, Ontario, by 6:30 A.M.
on November 3, and of the high over northeast Texas.
This

through Minnesota and Wisconsin.

TEMPERATURE RANGE

combination produced strong northwest winds

The average and minimum daily temperatures at
Winnipeg, Manitoba, from mid-October through November
10, 1955, are shown in fig. 7. There was a sharp de-
cline in temperature at Winnipeg on October 23 and 24,
followed by a pronounced warm wave on October 25 and
26. Temperatures started dropping on October 27. The
average temperature declined steadily from then until
November 3. The minimum temperature declined for 3
days, rose on October 30 and 31, and declined again on
November 1, 2, and 3.

18

DIRECTION, SPEED, AND ALTITUDE OF FLIGHT °

Observations on the 1955 mass migration of water-
fowl from the Great Plains of Canada into the Missis-
sippi Flyway of the United States yielded information
on direction or lines of flight, fig. 8, as well as on
speed and altitude of flight. Accounts of flights of
waterfowl over the Great Plains of Canada, the eastern
regions of North Dakota and South Dakota, western and
southern Minnesota, and parts of Wisconsin and Missouri
made it evident that long flights were made without the
benefit of landmarks provided by river systems. Never-
theless, concentrations of waterfowl observed following
river valleys made it clear that at times the birds used
river valleys as guide lines.

Lines of Flight.--Especially large numbers of
waterfowl were observed following the Missotri River
valley from central North Dakota to northern Missouri.
One flight line apparently broke away from the Missouri
River above Pierre, South Dakota, where the river bends
sharply to the southeast, and crossed Nebraska to
reservoirs near North Platte. This assumption is based
upon a hiatus in the migration noticed to the west and
another to the east of the North Platte region in
Nebraska and upon the lack of migration immediately to
the west of the easternmost counties of Kansas.

The flight of waterfowl following the Mississippi
River valley increased steadily in numbers as the birds
moved southward toward St. Louis, Missouri. Feeder
flight lines crossing Iowa and northern Missouri from
the northwest to the southeast added their ducks to the
main stem flight line. In migrating southeastward across
Iowa, waterfowl were observed following the valleys of ©
the Wapsipinicon and Des Moines rivers.

Some flight lines moving southeast crossed the
Mississippi River and placed approximately 750,000
ducks in the Illinois River valley and western Indiana.
Small numbers of ducks moved into eastern Illinois and
western Indiana from due north.

From St. Louis southward, the direction of move-
ment of the main flight line was due south. This flight
line did not at all times closely follow the channel of
the Mississippi River but spread out as much as 40 or
50 miles to the east or west of it.

Small flight lines cut straight south over the Ozark
Mountains of southern Missouri. Some waterfowl utiliz-—
ing these lines of flight probably stopped in the ©
Stuttgart, Arkansas, area, while others probably con-
tinued straight south into Louisiana. In central and
western Louisiana, flocks of waterfowl were observed
arriving from due north, indicating they had not followed
the Mississippi River flight line.

Although populations
Michigan and Ohio as a result of this early November ~

waterfowl increased in

— AVERAGE TEMPERATURE
--- MINIMUM TEMPERATURE

TEMPERATURE, DEGREES FAHRENHEIT

iS ely, 19 zl
OCTOBER

2a. £2097 21 29 3

2 4), 6s 387 10
NOVEMBER

Fig. 7.--The minimum and average daily temperatures from October 15 through November 10, 1955, at Winnipeg, Manitoba,

Canada,

flight, observations indicated that the increase was
small compared with that in the western and central
regions of the flyway.

Speed of Flight.--The mass waterfowl migration of
1955 moved with unusual rapidity from the Great Plains
of Canada to the marshes of Louisiana. The exodus
started from southern Alberta and Saskatchewan on
October 31 and from Manitoba on November 1. The
flight in the western sector of the Great Plains moved
ahead of the flight in the eastern sector.

By early morning of November 1, the flight was in
full force through North Dakota and along the northern
part of the Missouri River in South Dakota. As interpo-
lated from field reports, part of the flight was moving in
front of and part was moving behind the cold front
progressing southeastward through South Dakota and
North
Minnesota, the flight appeared near Detroit Lakes at
11:00 A.M. and, at other points, from 1:00 P.M. through
the afternoon. In east-central South Dakota it was first

Dakota, fig. 4. Farther east, in west-central

19

AREA OF OBSERVATION
DIRECTION OF FLIGHT

«-— INTERPOLATED LINE OF
FLIGHT

Fig. 8.--Areas of observation and directions of observed lines of waterfowl migration, November 1-3, 1955.

20

noticed at 2:00 P.M. By late afternoon the vanguards

had reached southern Minnesota and northwestern Iowa.

Shortly after sunrise on November 2, the vanguards
of migrating waterfowl reached Reelfoot Lake, Tennes-
see, and northern Arkansas. Later in the day, they
showed up in northern Louisiana. The rear echelon of
migrating waterfowl, which left southern Canada on
November 1, reached Louisiana on November 3.

It is between 1,400 and 2,000 miles from various
waterfowl southern Saskatchewan and

marshes _ in

Manitoba to southern Louisiana. Many thousands of

ducks made this flight in 2 days. At an average speed

4

of 40 miles per hour, these waterfowl would have flown
this distance in 35 to 50 hours. It appears likely that
some waterfowl made this flight without stopping.

While large numbers flew during the night, other
waterfowl alighted on lakes and marshes to spend the
night and resume migration the following day. The
flight schedule is illustrated by population changes at
Crane Lake, Bath, Illinois, where numbers rose from
65,000 in the morning to 120,000 by evening of Novem-
ber 2 and declined to 85,000 by the morning of Novem-
ber 3, and by Sieh’s observations of mallards which
alighted on Big Spirit Lake, Iowa, the afternoon and
night of November 1 and took flight periodically through-
out the morning of November 2.

Altitude of Flight.--Under fair weather conditions,
waterfowl may fly so high as to be invisible, or almost
so, to the naked eye. In aviating over Illinois, we have
found ducks at maximum altitudes of 3,000 to 4,000
feet.
waterfowl commonly fly at much lower altitudes.

The storm conditions which prevailed at the time
of the November 1 and 2 waterfowl migration resulted in
the birds flying so low as to be readily visible from the
ground. In North Dakota they were observed flying at
200 to 300 feet, so low that many of them were shot. In
Minnesota, the highest ducks observed from a plane

Under storm conditions, or over large rivers,

_were at 800 feet, the lowest at 100-150 feet. Observers

near several Iowa rivers estimated that flocks of ducks
were flying at 100 to 800 feet. Over the state of Mis-
souri, large numbers of migrating waterfowl were only
100 feet above the ground. Over the Mississippi River
valley in Illinois, flocks of ducks were stacked at ele-
vations of 200 to 2,000 feet. For a distance up to 40
miles west of the Mississippi River in southern Mis-
souri, mallard flocks were at altitudes that ranged be-
tween 400 and 1,000 feet. Observers in a plane over
northern Arkansas saw mallards flying at 1,500 feet.

SPECIES IN FLIGHT

Probably all species of ducks common in the
Mississippi Flyway, with the exception of the blue-

winged teal, were involved in the mass migration of
October 31 and November 1 and 2, 1955. However, all
observers concurred that the flight was predominated by
the mallard, followed in numbers by the lesser scaup.
Other species which appeared to be important com-
ponents of the flight were the gadwall, pintail, green-
winged teal, widgeon, and canvasback.

EFFECT OF WEATHER ON FLIGHT
The mass_ waterfowl emanating from
southern Alberta and Saskatchewan on October 3] and
southern Manitoba on November 1, 1955, was undoubt-

edly influenced by several components of weather.
Which was the most important in triggering the migration

migration

is difficult to determine.

Barometric Pressure.--Weather conditions in Al-
berta, Saskatchewan, and Manitoba on October 3] and
November 1, 1955, were associated with two low pres-
sure areas. One low pressure area moved across the
Great Plains from Alberta to Manitoba. The other low
pressure area moved from Wisconsin to Churchill, Mani-
toba, where it deepened to influence weather conditions

over much of the continent.
In a recent book on waterfowl, Hochbaum (1955:106-

7, 137) stated that ducks select anticyclonic (high
pressure) weather for the start of their mass migrations.
He cited a specific observation on October 30, 1954,
and “‘many similar observations’’ as evidence that high
pressure, with its attendant clear sky and favorable
wind, is a prerequisite for the beginning of mass mi-
gration. Certainly the migration which took place during
the period October 3l-November 3, 1955, the largest
waterfowl movement in the Mississippi Flyway since
November 11, 1940, was not begun under these con-
ditions. Neither was the famous waterfowl migration on
November 11, 1940, which was initiated by weather con-
ditions associated with a deep low; the low moved
rapidly into the Mississippi River valley from the south-
west, creating the ‘‘Armistice Day storm’’ which made
history.

Wind.--Recent studies of small birds strongly sug-
gest that wind direction is an important factor in the
initiation of their migration.

Devlin (1954:93) correlated wind direction with
autumnal, nocturnal migration and concluded that birds
were in flight on nights with light to moderate north or
northwest winds. After studying bird migration in
Lincoln Park, Chicago, Bennett (1952:219) concluded
that ‘*The autumn migration waves are associated with
cold fronts followed by strong NW to N winds.

Dennis (1954:111) concluded after observing the
spring migration of birds in Texas that ‘Southerly

”

winds, rising temperature, and falling barometric pres-

21

Table 5.--The wind direction and the wind velocity in miles per hour for certain hours of the day, November 1

or 2, 1955, at several weather stations from southern Manitoba to southern Louisiana.

Hour of Winnipeg, Minneapolis,
Day November 1] November 1
0 Wars
1 W 13 WNW 13
3 W 14 NW 12
6 W 15 SW 11
9 W 16 Sow 13
12 *W 20 WSW 23
15 *W 16 WSW 23
18 *W 13 *WSW 11
21 *W 19 *OW 13
24 *W 24 *W 13

Peoria, Memphis, Baton Rouge,
November 2 November 2 November 2
NE 9 S 20 ESE 8
*N 9
*N 12 S17 ESE 8
*N 17
*N 19 sta) ya SSW 14
NW 23
NW 23 *NW 25 *SSW 17
NW 17
W 13 NNW 18 *NLIS

*Hour of passage of spectacular waterfowl migration of late October and early November, 1955.

sure generally attend the departure of migrants.”
Raynor (1956:171) tentatively concluded that stable air
and favorable winds aloft were of great importance for
nocturnal bird migration during the spring.

Hochbaum (1955:104) stated that every major flight
of blue-winged teals in September, canvasbacks and
redheads in October, and lesser scaups and mallards in
November occurred with a west-east opposition of high
and low pressure areas, with a trough of wind flowing
down the middle between the two air masses. He used
the weather map of November 7, 1947, to illustrate the
favorable flow of air for the waterfowl migration which
occurred at that time.

Weather maps for October 31 and November 1, 2,
and 3, 1955, figs. 3-6, show wind directions and veloci-
ties near ground level by means of arrows, and above
eround level up to about 2,000 feet above ground level
by means of isobars. The wind flows along the isobars;
the closer the isobars, the higher the wind speed. The
wind circulates counter-clockwise around a low pres-
sure area, the reverse around a high pressure area.

Because, during the mass migration of 1955, water-
fowl were migrating between a few hundred and 2,000
feet above the earth, they were under the influence of
winds shown by both arrows and isobars. The winds
were only partially favorable for southward migration.
They were not beneficial on October 31 and November 1
in Manitoba, the Dakotas, Minnesota, and Wisconsin,
when they were largely from the west at almost right
angles to the line of flight. Table 5 shows the wind
directions and velocities on certain hours during the
period the mass migration passed several weather sta-
tions in the Mississippi Flyway. Seldom did the migrat-
ing waterfowl have a tail wind.

Wind directions were at least as favorable on
October 29 as during the period October 31-November 2;

22

yet comparatively little migration occurred on October
29.

Over a large area of flight on November 1-3, 1955,
waterfowl were migrating through turbulent air, through
snow showers in the northern sector, and under a layer
of low, dense, and extensive clouds. Such conditions
certainly made for hazardous flight and difficult navi-
gation.

Temperature.--An interpretation of the effect of
cold fronts on the mass waterfowl migration of 1955 is
difficult because of the complicated frontal structure
over the period of the migration. A cold front of Mari-
time and Continental Polar air, shown over the north-
western United States on the weather map for October
31, fig. 3, passed down the flyway to the Midwest as a
secondary cold front of Continental Arctic air was mov- |
ing behind it in southwestern Canada and northwestern ©
United States, fig. 4. The leading edge of the secondary
front was so diffuse as to make its position quite un-
certain. In fact, the secondary front did not appear on
the weather map for November 2, fig. 5. Eventually it
combined with the Polar cold front on November 2 north
of Memphis, fig. 5. The passage of a secondary cold
front at a given point can best be ascertained by tem-
perature decline. Usually winds shift with the passage
of a front, but such was not the case with the secondary
cold front shown on the weather map for November 1,
fig. 4.

The average daily temperatures at Winnipeg, Mani-
toba, fell for 4 successive days before the mass mi-
gration started from Alberta and Saskatchewan on
October 31 and 5 successive days before the migration
started from Manitoba on November 1. Temperatures for
this period are shown in fig. 7.

On November 1, the average temperature was 26.0
degrees and the minimum temperature 23.2 degrees,

WINNIPEG 370 MI.— MINNEAPOLIS +— 340 MI.—* PEORIA +— 380 MI.—~+ MEMPHIS =— 330 MI.— BATON ROUGE

76

72
—=——. TEMPERATURE

A —+— MIGRATION

TEMPERATURE IN DEGREES FAHRENHEIT

ea iG: 8

LOW N2R 14 s16GW18 20) 22242) <4

NOV. |

NOV. 2 | ip

SOMI2 4 N6MI8S 20522524 225 4 kG Be tO) ele 146

HOURS OF THE DAY

Fig. 9.--Hourly temperatures reported by weather stations at Winnipeg, Minneapolis, Peoria, Memphis, and Baton Rouge
on the day before and the day on which the mass waterfowl migration of 1955 passed through the region of each of these
cities; also the hours of greatest migration (indicated by heavy horizontal line) in each area, as interpolated from field

reports.

while, on October 24, the average temperature was 30.8
degrees and the minimum was 16.6 degrees.

It is apparent that the minimum temperature on
October 24 did not affect waterfowl migration to the ex-
tent a higher minimum did on November 1. It appears
that the cumulative effect of the cold was more im-
portant in initiating migration than a single sharp drop
in temperature.

Fig. 9 shows the hourly temperatures reported by
five weather stations on the day before and the day on
which the mass waterfowl migration of 1955 passed
through the region of each of these stations. The sta-
tions were spaced almost equidistantly along the line
of migration.

It is apparent that the mass waterfowl migration
was well underway at Winnipeg, Manitoba, before the
Continental Arctic air mass began to depress the local
temperature at hour 15 on October 31. By hour 24, the
temperature had dropped 10 degrees below the minimum
of the previous day.

The front of Continental Arctic air pivoted around
the low pressure area centered in southwestern Mani-
toba to swing eastward, thereby dropping the tempera-
ture at Minneapolis, Minnesota, at almost the same time
as at Winnipeg. At Minneapolis the waterfowl flight
arrived with the mass of Continental Arctic air, which

dropped the temperature 7 degrees below the minimum
of the previous day.

The main body of the waterfowl flight arrived at
Peoria, Illinois, in advance of the mass of Continental
Arctic air, which commenced to drop temperatures there
at 1 P.M., November 2. Temperatures fell 17-20 degrees
below minimum temperatures of the previous afternoon
and night.

At Memphis, Tennessee, part of the main body of
the waterfowl flight arrived before and part with the
of Continental Arctic and Polar air, which
dropped temperatures 22-24 degrees below minimum
temperatures of the previous evening and night.

The Arctic and Polar air mass arrived at Baton
Rouge, Louisiana, during the early morning of Novem-
ber 3, dropping the minimum temperature 10 degrees.
Arrival of the waterfowl flight was concomitant with

mass

arrival of the cold air.

Precipitation.--When snow covers waste grain in
harvested fields to the extent that it makes for diffi-
culty in the feeding activities of mallards and pintails,
an exodus of these species may occur. The extent of
the exodus depends usually upon the depth of the snow.
The small amount of snow that had fallen on the Great
Plains of Canada by November | was not sufficient in
itself to account for the mass departure of mallards and

23

pintails, nor to account for the complete departure of
teals, widgeons, gadwalls, and diving ducks.

Analysis of Effect of Weather on Migration.--The
effect of weather in initiating the mass waterfowl mi-
gration of October 31-November 1, 1955, is evaluated
as follows: Low pressure areas in Canada resulted in a
southward flow of a mass of Continental Arctic air. The
low temperatures resulting from Continental Arctic air
triggered the flight from the Great Plains of Canada and
the United States. The flight moved faster than the cold
air mass, so that at Winnipeg, Manitoba (where a sta-

tionary front slowed the southward flow of cold air), the
migration of waterfowl was in advance of the Arctic air.

Because of a swinging gate action of the Arctic
air, which pivoted around a low pressure area in south-
western Manitoba, the waterfowl flight arrived at Minne-
apolis with the cold front. By the time the flight reached
Peoria, Illinois, it was again in advance of the Arctic
air. The southward movement of cold air accelerated
between Peoria and Memphis, Tennessee, so that part
of the waterfowl flight arrived at Memphis before and
part of it with the cold air.

LITERATURE CITED

Bennett, Holly Reed

1952. Fall migration of birds at Chicago. Wilson Bul. 64(4):197-220.

Devlin, Joseph M.

1954. Effects of weather on nocturnal migration as seen from one observation point at Philadelphia. Wilson

Bul. 66(2):93-101.
Dennis, John V.

1954. Meteorological analysis of occurrence of grounded migrants at Smith Point, Texas, April 17-May 17,

é 1951. Wilson Bul. 66(2):102-11.
Hochbaum, H. Albert

1955. Travels and traditions of waterfowl. University of Minnesota Press, Minneapolis. 301 pp.

Raynor, Gilbert S.

1956. Meteorological variables and the northward movement of nocturnal land bird migrants. Auk 73(2):153-

Tey
Smith, Harry R., and Paul W. Parmalee

1955. A distributional check list of the birds of Illinois. Ill. State Mus. Pop. Sci. Ser. 4. 62 pp.

24

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