Migration observed from the south
WINGIN’
IT
By
Kate Crowley
Since I’m not home
right now to keep track of arrivals, my informants have told me that the Canada
geese and sandhill cranes have been seen flying over. Julie Salmon posted a picture of two geese
standing on the still frozen Moose Lake; they know there is open water flowing
under the bridge and into the river (again).
On the Mississippi River last week we were constantly on the lookout for
new birds and figured we’d see a lot of waterfowl, but surprisingly we saw few.
This is the far southern end of the river, where it is wide and portions of it
north of New Orleans have massive industrial installations along the banks, so
good habitat is scarce until you get above Baton Rouge.
The river is part of
the mega ‘highway’ for the birds (known as a Flyway) that are returning north
after their winter break. Before the
river was constricted by locks and dams in the northern half and levees in the
southern portion, there were vast floodplains, wetlands and wet forests that
absorbed, sheltered and fed millions of migrating birds. While it is impossible to know or measure the
actual reduction in numbers because of the changes to the habitat, is
nonetheless a shadow of its former self.
The list of birds that
we saw from the deck of the Paddlewheel boat we were riding on included
laughing gulls in the port of New Orleans, double crested cormorants all along
the route, white pelicans, three great blue herons and a flock of lesser scaup
(ducks) as we neared Memphis. The river is high with water flooding some of the
low lying island forests, but it is not considered in flood stage until it
starts to rise up along the levees.
There was also a cold snap last week, with morning temperatures at
freezing or below in Louisiana and Mississippi.
Weather conditions can hold some of the birds back.
The Canada geese that
you are seeing flying over now and hanging out on still frozen lakes are the
vanguard, the risk takers, as I’ve described in the past with different songbirds
who arrive ‘too early’. They are the
ones who will be hit by late season snowstorms
and freezing temperatures (and we know we will still see some of these in
April), but if they can survive those few tough weeks, they will
be the proverbial ‘early birds’ who not only get the worm, but the best nest
sites.
The population of these
large waterfowl in Minnesota (and many other states) has been growing
exponentially in recent years. They love the perfectly groomed lawns of golf
courses and suburban homes where they can graze without having to worry about
predators hiding in tall grass. And they are prolific breeders. By 2 or 3 years of age a pair can begin to
produce young and they have a lifespan of potentially over 10 years. A pair raises,
on average, about 4 young per year. At that rate, a lake with 3 pairs of adult
geese could multiply to nearly 50 birds within 5 years and to over 300 in just
10 years.
Canada geese like many
other birds, return to same area where they nested the previous year, so the
ones you see on your pond or lake are probably ‘old’ friends.
The sandhill cranes
that are returning are also in pairs; like the geese they mate for life, which
is why they are symbols of fidelity in Asian cultures. We took it as a good omen when a pair flew
over us in our front field the day we were married 27 years ago.
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