Story by Bryan Pfeiffer
BIRDS in focus
Diminutive cackling geese are occasionally seen with much larger Canada geese.
by relocating and reestablishing maxima in the U.S., in part to
The restoration went a bit viral. Canada geese, ruthless
opportunists, are among the few birds able to digest lawns,
which began to proliferate with the mid-century spread of
suburbia. Feeding and nesting in parks, golf courses, farms, and
airports – especially those near lakes and small ponds – the
giants pushed southward beyond the Canada goose’s historic
range. A semicolonial breeder to the north, the Canada goose
can also nest alone. It now breeds in every state.
In many of these new frontiers, Canada geese have lost their
need (or will) to migrate and have become year-round residents
in places where previously geese only came to visit for winter.
And in some locations, Canada geese have become a nuisance,
particularly in small ponds, in neighborhoods, and at airports.
The Canada goose now exhibits a variety of races and
behaviors. The migratory geese breed in northern North America
and winter as far south as Mexico, and resident birds live across
the United States year-round or don’t migrate very far. A “mixing
of the races” has also blurred some of the genetic and behavioral
distinctions between related species. These lines have always
been a bit fuzzy; human relocation and manipulation has made
them even more so.
So have another look at those geese overhead. They may not
be heading south for winter, and a few of the noticeably smaller
ones might not even be Canada geese. One of the most iconic
symbols of autumn turns out to be iconoclastic.
Bryan Pfeiffer is an author, wildlife photographer, guide, and consulting naturalist who
specializes in birds and insects. He lives in Montpelier, Vermont.
The Canada geese now honking
overhead in V-formation, perhaps
more than any other birds,
exemplify the fall migration.
Except when they’re not really
migrating, and except when
they’re not really Canada geese.
One of the most familiar birds
on the continent fractures our
notions of predictability and
uniformity among wildlife.
Yes, historically these geese
were in large part Canadian,
breeding throughout the low
Arctic from the Aleutians to
Newfoundland and south into the
northern United States. Across
that range, Canada geese exhibited a high degree of philopatry
– the tendency of an animal to stay in or return to its place of
origin. Over the course of their evolution, though, these geese
split into somewhat distinct breeding populations. As a result,
biologists and birders recognized 11 subspecies, varying mostly
by size – smaller to the north and west, and larger to the south.
The largest goose in the world, for example, is the “giant”
Canada goose (Branta canadensis maxima), and one of the
smallest – not much bigger than a mallard – is a subspecies
known as “minima.” This range of body sizes would be similar to
one race of humans standing six feet tall and another race barely
three-and-a-half feet tall.
This unusual variation in size – perhaps the most extreme
among all birds – set the stage for a redefinition of what it means
to be a Canada goose. In 2004, the American Ornithologists’
Union split the bird known as the Canada goose into two species.
The four smallest groups – and for the most part the darkest,
including the tiny minima – are now called the cackling goose
(Branta hutchinsii), and the seven other subspecies remain
Most of the cackling geese (birders affectionately call them
“cacklers”) migrate south through central Canada and winter in
the central U.S. But strays occasionally show up in the eastern part
of the country, which means that those diminutive, stubby-billed
geese you might find among the bigger geese are not actually
Canada geese – at least, not anymore.
But more than changing the way we name this goose,
humans also altered its distribution and migration patterns. By
the end of the nineteenth century, overhunting, egg collection,
and the destruction of wetlands depleted Canada goose populations, particularly in the southern portion of the bird’s range.
In the 1930s, federal and local wildlife managers responded