Hi monroe22,
Thank you for a very interesting question.
What you are referring to is called the 'year-round resident Canada
Goose'. The Great (Giant) Canada Goose has a weak migratory instinct
and will stay in place as long as there is ice-free water and
available food.
The instinct hasn't been erased. Basically, what has happened is when
hunting with live decoys was outlawed in 1935, some former market
hunters kept and cared for their flocks. Others released them in the
nearest bay or marsh or gave them away. In the Atlantic Flyway alone,
an estimated 20,000 birds were freed. Towns and parks and individuals
everywhere gladly adopted them, feeding and protecting them for the
novelty of having Canada geese nearby.
Even though their wings were no longer being clipped, the former decoy
flocks did not resume their ancient migrations. Their migratory
instincts were intact, but goslings learn the details of behavior from
their parents and other adult geese. In the earthbound decoy flocks,
after three or four or five generations in captivity, there were no
birds remaining that had ever participated in, say, the spring nesting
migration from the lower Mississippi Valley to northern Manitoba.
Also, during their captivity, decoy geese had become conditioned to
residing year-round in a single location and relying upon their human
keepers for food. After release, there was little biological incentive
for the flocks to change their behavior.
=========
"The problems of year-round resident Canada geese exist on a national
scale. Habitat changes caused by people have encouraged the geese to
remain year-round.
Because people are willing to feed them and often keep their ponds
ice-free in the winter, the geese have begun sticking around in
suburbia. They have become accustomed to cars, planes, and other
noises of modern life. In fact, they are so used to cars that they are
willing to walk out in front of oncoming traffic, secure in the
knowledge that the cars will stop for them.
The suburban landscape contains food and space to support a few geese
without causing too much difficulty for people. Giant Canada geese,
however, like to stay around where they are hatched, in the same way
that migrating geese tend to return to the same spots year after year.
The lack of predators and abundance of food allows giant Canada geese
to lay more eggs and have more goslings survive to adulthood than
would be normal in the wild, so a small population can quickly grow
into a large population. In addition, the presence of geese and
goslings (as well as ducks) is an attractant to other giant Canada
geese who might have been displaced from another area."
(Read entire article Illinois EPA (Environmental Protection Agency)Canadian Geese
http://www.epa.state.il.us/water/conservation-2000/lake-notes/canadian-geese/
=========
Audubon: Birds "Why has the Canada goose stopped migrating?"
http://magazine.audubon.org/birds/birds0003.html
The Geese That Came in From the Wild
"For the most part, however, these birds don?t travel. In fact, some
people call them lawn carp, or couch-potato geese. Every one of these
birds was born here and will remain here lifelong, thriving amid
humanity, devouring cultivated grass and stale bread, begetting
progeny and grandprogeny and great-grandprogeny, seldom flying more
than two or three miles from its birthplace, and never facing the
rigors of migration. Scott Smith, the biologist in charge of the
roundup, says the odds are greater that one of them will venture into
a checkout line at Filene?s than into the air for a 1,400-mile flight
to the nesting grounds on Quebec?s Ungava Peninsula."
[...]
"In the late 1960s, when north Americans first began to notice small,
scattered clusters of Canada geese that flew strangely low to the
ground, nested on local lakes, and sometimes came close enough to be
hand-fed a Dunkin? Donut, we were both bewildered and delighted.
Whether we lived in Pennsylvania or Iowa or Colorado, the Canada goose
most of us knew was an aloof and far-flying migrant, a longtime symbol
of wildness and wanderlust. Few people had seen the birds any closer
than 1,000 feet overhead, flying in elegant V formations to and from
their remote nesting grounds, which stretch cross-continent, from
Newfoundland to the Aleutian Islands.
These new and up-close geese, most people assumed, were members of
that annual stream of wild migrants that for reasons unknown had
suddenly changed their age-old behavior.
"The question I?m most often asked by the public," says Jay Hestbeck,
a senior wildlife biologist with the U.S. Fish and Wildlife Service,
"is, ?Why has the Canada goose stopped migrating?? "
The short answer is, it hasn?t. In the continent?s four migratory
flyways, the several wild subspecies of Branta canadensis (some say
there are 8, some say 11 or more) regularly fly north and south more
or less as they have since the last ice age.
What we observed with wonder in the 1960s was the beginning of the now
well-known phenomenon of resident Canada geese. Today an estimated 4
to 5 million members of the species live cheek by jowl with
civilization, year-round, in every state except Hawaii and in every
Canadian province. And most of us see them not as wonders of nature
but as pests, polluters of land and water and an insult to the genes
of wild goosedom."
[...]
"When hunting with live decoys was outlawed in 1935, some former
market hunters kept and cared for their flocks. Others released them
in the nearest bay or marsh or gave them away. In the Atlantic Flyway
alone, an estimated 20,000 birds were freed. Towns and parks and
individuals everywhere gladly adopted them, feeding and protecting
them for the novelty of having Canada geese nearby.
Even though their wings were no longer being clipped, the former decoy
flocks did not resume their ancient migrations. Their migratory
instincts were intact, but goslings learn the details of behavior from
their parents and other adult geese. In the earthbound decoy flocks,
after three or four or five generations in captivity, there were no
birds remaining that had ever participated in, say, the spring nesting
migration from the lower Mississippi Valley to northern Manitoba.
Also, during their captivity, decoy geese had become conditioned to
residing year-round in a single location and relying upon their human
keepers for food. After release, there was little biological incentive
for the flocks to change their behavior. In northern states, when lake
ice froze beneath them and snow covered the ground, flocks were forced
to depart temporarily. But they typically flew only far enough?50
miles, 150 miles?to find the nearest open water and manmade food
supply. The former decoy flocks thrived and slowly spread.
Meanwhile, Americans had been moving westward across the Midwest and
the Great Plains. In both the United States and Canada, they often
killed and ate geese, robbed their nests of eggs, and captured
goslings to raise for food. This pressure, in addition to that of
market hunting, severely depleted the numbers of the large,
short-migrating Canada geese that inhabited that part of the
world?Branta canadensis maxima, which averaged roughly 10 to 16
pounds. By the 1920s most wildlife biologists were convinced that the
subspecies had been completely wiped out."
[...]
"At least one wild flock remained as well, nesting in southeastern
Manitoba and wintering in Rochester, Minnesota. But it was not until
1962 that an Illinois biologist, Harold Hanson, systematically weighed
birds from this flock to prove that there were indeed survivors of the
once bountiful "giant Canada geese."
[...]
=========
A detailed 4 page article can be found at
Lake Notes Canada Geese
http://www.pacd.org/resources/lake_notes/geese01.htm
"Unlike the migratory Canada goose, whose numbers are again in decline
due to poor survival and reproductive rates, the population of
resident Canada geese residing in suburban America has skyrocketed in
the last ten years. These birds are full-time residents who don?t fly
away with the first chill. They are big and intimidating, hissing and
charging in defense of their territory. There are so many of them that
even their ordinary honking can become irritating. They have been
known to eat turfgrass down to a nub and then leave uncountable piles
of slimy green droppings. And, they can contribute to the spread of
waterborne diseases, such as giardia and cryptosporsis, which have the
potential to affect humans.
Canada geese have 11 subspecies. These subspecies range in size from
29 to 38 inches in length and 6 to 12 pounds in weight, with the
smaller populations generally living further north. In 1965, a
biologist found a population of the subspecies Branta canadensis
maxima, the giant Canada goose, which had been thought to be extinct.
Since its rediscovery, the giant Canada goose has recovered more
quickly than any other subspecies and now makes up the bulk of our
resident goose populations. There are estimated to be as many as 1
million giant Canada geese in the Atlantic flyway, as many as all
other Canada geese subspecies in the flyway combined.
For the Canada goose, ?paradise? might be defined as acres of short
tender grass, a freshwater pond for drinking water and security, and
no predators. It would look much like a public park, corporate office
campus, golf course, cemetery, or waterfront yard. However, while
other Canada goose subspecies are wary of humans, giant Canada geese
are predisposed to ignore people. The biologist who rediscovered the
giant Canadians noted that the ?placid disposition of the giant Canada
goose sets it apart from all others.?
Placid disposition or not, the giant Canada goose has adapted well to
living among us. They have a weak migratory instinct and will stay in
place as long as there is ice-free water and available food. Since
people are willing to feed them and often keep their ponds ice-free in
the winter, the geese are truly at home in suburbia. They have become
accustomed to autos, planes, and other noises of modern life. In fact,
they are so used to cars that they are willing to walk out in front of
oncoming traffic, secure in the knowledge that the cars will stop for
them."
(click through Page 2 - 4)
=========
keyword search:
great canada goose migratory instinct
giant canada geese migratory instinct
year-round resident Canada Goose
=========
Best regards,
tlspiegel |
