I watched as my friend scattered corn for the family of Canada Geese.
There was mom and dad and five goslings already approaching their
parents in size. Jokingly and flippantly I said something like:
“Fattening up the tender goslings for your Christmas dinner.”
He
shot me daggers! He did not think that was the least bit funny. This
pair of geese returned year after year to his farm pond. They were
dearly loved pets, and you don’t joke about dining on your pets.
In
half a dozen places around our county, I have seen home-made roadside
signs cautioning drivers about a goose crossing - usually with a graphic
of parent geese leading their line of young.
Young
goslings are admittedly very cute. It is almost impossible not to say,
“Ahhh, aren’t they adorable,” when you see them scrambling after an
adult goose.
The protective attentiveness of parent
geese to their young is commendable, and very effective. If you don’t
pay too close attention, goose parenting could provide fodder for the
family-value moralists.
But ... if you do pay
attention, you might ask why a pair of geese are protecting a dozen or
more goslings when they normally lay only six eggs. A couple of years
ago, I watched two adult geese leading twenty-three goslings in the
Retreat Meadows; I was able to count the moving number when I had my
photograph on the monitor so that the birds stayed still. Behind that
group came another pair of adults leading sixteen youngsters. These were
only two of the gosling collections scattered around those waters.
A
friend on Newfane Hill wondered why the nesting geese and all of their
recently hatched young disappear a few days after hatching. Did snapping
turtles grab all of the young, leaving the adults to fly off? Or is
something else happening? A farm pond in Brookline has one nesting pair
of geese, but through the summer, several families use the pond and farm
fields to raise their young. Where did the other families come from?
Canada
Geese have become so common, that I could elicit many reports of geese
families that disappear from small ponds, or of larger ponds and bogs
that host several grazing families and many goslings. But what’s
happening?
The Canada Goose (she is a goose, he is a
gander) lays a big egg - about 3 inches in length. Physiologically, she
is designed to incubate six eggs. If there are more than six eggs in a
nest, it may be due to another goose having dumped an egg in her nest.
The large, nutrient rich eggs of the Canada Goose result in “precocial”
hatchlings - they are relatively well-developed, have a thick coat of
natal down, and are able to feed themselves almost immediately. Parents
show their young what to eat and watch out for dangers. Parenting of
precocial young is easy. By contrast, songbird hatchlings are altricial -
helpless, naked, eyes closed, and totally dependent upon their parents.
Parenting of altricial young is hard work.
The
parenting of a dozen young goslings is relatively easy, since they can
feed themselves. But a typical clutch of eggs is only six. What’s going
on in goose society?
Bern Heinrich (The Geese of Beaver Bog)
noticed that his pair of Canada Geese disappeared with their six
hatchlings after only a couple of days. Curious, observant, tenacious
(he made notes for several years) and a little lucky, he discovered that
his pair led their hatchlings through the woods to another larger pond
with good grazing fields where they joined the resident breeders of that
pond. The new pond was about three miles from his beaver bog. Other
pairs also came to the new pond.
At the new pond, other
goose dynamics took over. The six goslings of Heinrich’s pair were
adopted by the resident geese, and his pair returned to his beaver bog.
They stayed for a while, then probably flew north to Quebec where they
joined other geese on a “molting” territory where numbers and remoteness
would protect them during their summer feather molt when they are
unable to fly.
Meanwhile, the resident pair
successfully protected their own six goslings and their six adopted
goslings - this in spite of the fact that their favorite grazing field
was also the home of a red fox. The ever-alert gander warned off the red
fox, and the fox wisely decided not to challenge his powerful beak or
wings.
Hatchling
geese imprint on what they first see and follow that form. Hence, when
they see their parents at hatching, they imprint on them and follow them
through the woods. But it seems that imprinting on specific individuals
of that form takes place a few days later. If they are in the presence
of other adults, they may imprint on those adults, rather than their
hatch parents. Since all they need is some protection and leadership, it
is not a big burden to the adoptive parents. They can guard a dozen as
easily as they can guard half a dozen - or, given what I saw in the
Retreat Meadows, two dozen.
But why do these adoptions
occur in the first place? One would think that the parents would have a
genetic self interest in staying with and protecting their own
offspring.
There
are probably several explanations, but protecting turf from outsiders
seems to be one factor. John Anderson has been watching the resident
geese on Sunset Lake for many years. A few years ago, two pair nested
and hatched young. Not long after the hatching, he watched the resident
gander attack the second gander who had had the gall to intrude on his
lake. This was not a wing-flapping, goose-hissing confrontation, but an
out and out physical fight. The second pair of adults left, and the
resident pair adopted their goslings.
Canada Geese are
longed lived, perhaps twenty or more years. They usually begin breeding
in their third year and have a strong fidelity to their nesting
territory, returning to the same place year after year. If they have
friendly human neighbors, they will establish neighborly relations. A
friend has scattered corn for the resident pair at his camp for many
years. One summer, he got a new truck. The next spring when the road
finally opened, he drove in to the camp. He saw a pair of geese at one
end of the lake. By the time he got to his camp half-way down the small
lake, the pair was waiting for him and his corn. They not only
remembered him - they remembered his new truck.
Canada
Geese have become so familiar that it is easy to overlook their
fascinating complexity. They have society and culture, loves and hates,
just as we do.
Good birding!
For more on the Canada Goose, see Bern Heinrich, “The Geese of Beaver Bog,” 2004.
Fascinating. I found a Canada Goose nest earlier this spring and counted 18 eggs in it with one adult brooding. I had never considered that its body was only adapted to brooding six eggs and that all the additional eggs may have been deposited by another mother.
ReplyDeleteI remember reading once that occasionally two male geese will bond and adopt goslings together, and that male-male pairs are actually even more successful than male-female pairs at raising young because two aggressive males can defend a better territory. In any case, goose families are definitely worth a closer look!
ReplyDeleteOh wow, great shots. NIce post and great information. I really like the canadian geese and love watching them. We have Furman University near by with a huge lake and there are always canadian geese landing there late evenings. The other day I was headed home and seen a bunch of them in a school play area so I stopped and got a few pictures. check out my pictures.
ReplyDeleteMichael
Canadian Geese