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| Canada Geese on ice, lower Okanogan River near confluence with Columbia River in Okanogan County, N.E. Washington. |
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| Small flock of Canada Geese in January flight over the confluence of the Wenatchee and Columbia Rivers near Wenatchee in Washington State, U.S.A. |
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| Male gander displaying his prowess after chasing off a would be suitor to his nearby mate. |
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| A gaggle of Canada Goose during a migratory layover on a small, recently ice free pond in NE Washington State. |
One of the largest and most prolific North American birds is
the Canada Goose with a range extending from parts of Mexico into the northern
reaches of Canada. That’s a huge area spanning over 3,000 miles of latitude by
3,000 miles of longitude. But not all Canada Geese are migratory. And not all
Canada Geese are the same.
Doing a little research into this common avian I discovered
what appears to be an urban legend that a man named John Canada was the
taxidermist who first identified and classified the Canada Goose. He decided to
name the bird after himself, hence the name Canada Goose.
What I take to be more accurate is the first recorded use of
the name, 'Canada goose' appeared in 1772 in Carl Linnaeus' 8th-century work,
Systema Naturae. And later still James Audubon called it the Canada goose in
1836.
The differences of these geese rests in having at least 11
subspecies of Canada Goose currently recognized. In general, the geese get smaller as you move
northward, and darker as you go westward. And most recently the four smallest
forms are now considered a different species: the Cackling Goose.
Not everyone is enamored by this goose. In fact some folks
just darn right don’t like them. This often stems from territorial issues.
Prime Canada goose habitat is open marsh or field areas adjacent to waterways.
As far as the goose is concerned mowed yards, golf courses, and parks are
ideal. Geese can eat and digest grass and the open areas are perfect
observation areas for avoidance of predators. Remember these birds were an
important part of the diet for indigenous peoples and homesteaders alike. Fur
agent David Thompson often documented goose and their eggs amongst his
provision lists as noted in Jack Nisbet’s
book Map Makers Eye.
Most of us have heard that this species of geese mate for
life and pairs remain together throughout the entire year, although extra-pair
copulations have been documented. What I didn’t know is that these geese mate
“assortatively,” where larger birds choose larger mates and smaller ones
choosing smaller mates. Breeding for Canada Geese doesn’t usually occur until
their fourth year. During much of the year they associate in large flocks, many
of these birds within the flock may be related to one another.
Some migratory populations of the Canada Goose are not going
as far south in the winter as they once did. This northward range shift is
attributed to changes in farm practices that makes waste grain more available
in fall and winter, combined with changes in hunting pressure and climatic
changes.
The oldest known wild Canada Goose was 30 years 4 months old
and had been banded and studied over the course of it’s long life.
Cool Facts
•At least 11 subspecies of Canada Goose have been
recognized, although only a couple are distinctive. In general, the geese get
smaller as you move northward, and darker as you go westward. The four smallest
forms are now considered a different species: the Cackling Goose.
•Some migratory populations of the Canada Goose are not
going as far south in the winter as they used to. This northward range shift
has been attributed to changes in farm practices that makes waste grain more
available in fall and winter, as well as changes in hunting pressure and
changes in weather.
•Individual Canada Geese from most populations make annual
northward migrations after breeding. Nonbreeding geese, or those that lost
nests early in the breeding season, may move anywhere from several kilometers
to more than 1500 km northward. There they take advantage of vegetation in an
earlier state of growth to fuel their molt. Even members of
"resident" populations, which do not migrate southward in winter,
will move north in late summer to molt.
•The “giant” Canada Goose, Branta canadensis maxima, bred
from central Manitoba to Kentucky but was nearly driven extinct in the early
1900s. Programs to reestablish the subspecies to its original range were in
many places so successful that the geese have become a nuisance in many urban
and suburban areas.
•In a pattern biologists call “assortative mating,” birds of
both sexes tend to choose mates of a similar size.
•The oldest known wild Canada Goose was 30 years 4 months
old.
Canada Geese eat grain from fields, graze on grass, and
dabble in shallow water by tipping forward and extending their necks
underwater. During much of the year they associate in large flocks, and many of
these birds may be related to one another. They mate for life with very low
“divorce rates,” and pairs remain together throughout the year. Geese mate
“assortatively,” larger birds choosing larger mates and smaller ones choosing
smaller mates; in a given pair, the male is usually larger than the female.
Most Canada Geese do not breed until their fourth year; less than 10 percent
breed as yearlings, and most pair bonds are unstable until birds are at least
two or three years old. Extra-pair copulations have been documented.
During spring, pairs
break out from flocks and begin defending territories. Spacing of these pairs
is variable and depends on availability of nest sites and population density;
where population is large, even after a great many fights birds may end up
nesting in view of one another, and some populations are semi-colonial.
Canada Goose threat
displays may involve head pumping, bill opened with tongue raised, hissing,
honking, and vibrating neck feathers. When an intruding goose doesn’t retreat,
geese may grab each other by breast or throat and hit each other with their
wings. Fighting may result in injuries.
Female selects nest
site, builds nest, and incubates eggs. She may brood goslings in cold, wet, or
windy weather and while they’re sleeping for first week after hatching. Male
guards the nest while female incubates.
Soon after they
hatch, goslings begin pecking at small objects, and spend most of their time
sleeping and feeding. They remain with their parents constantly, though
sometimes “gang broods” form, especially in more southern latitudes. These can
include at least two broods, and sometimes five or more, that travel, feed, and
loaf together, accompanied by at least one adult.
Young often remain
with their parents for their entire first year, especially in the larger
subspecies. As summer wanes birds become more social; they may gather in large
numbers at food sources; where food is limited and patchy, may compete with
displays and fights.
In winter, Geese can
remain in northern areas with some open water and food resources even where
temperatures are extremely cold. Geese breeding in the northernmost reaches of
their range tend to migrate long distances to winter in the more southerly parts
of the range, whereas geese breeding in southern Canada and the conterminous
United States migrate shorter distances or not at all. Individuals tend to
return to the same migratory stopover and wintering areas year after year.
Spring migration may be difficult for observers to track because of
over-wintering birds and movements between nighttime resting areas and feeding
areas, but the bulk of spring migratory movements tend to move north behind the
retreating snow line, where the temperature is averaging 35 degrees.
Migrating flocks
generally include loose aggregations of family groups and individuals, in both
spring and fall. Flights usually begin at dusk, but may begin anytime of day,
and birds fly both night and day. They move in a V formation, with experienced
individuals taking turns leading the flock.
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