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September is the season of return - excluding,
of course, the after-Christmas return season. Students return
to school. My family tax refund returns to me (in theory).
But more spectacular, thousands of birds wing their way southward,
returning to their wintering grounds and, perhaps, what we
might call home.
Consider this. A tiny four-ounce rufous hummingbird, whose
name is longer than its body, whirrs its way northward in
spring to its breeding grounds in the lowlands and mountains
of the Pacific Northwest. By July, the males have already
arrived in Moab on the southward migration. His four months
on the breeding ground in the Pacific Northwest, British Columbia
or southern tip of Alaska does not make the rufous a resident.
Nor will he ever see a family tax refund. He will probably
have sired several generations of little rufouss and
split the country before I ever see a tax refund - whatever
a tax refund is. No, the rufous and many of his
neotropical migratory counterparts spend more time on their
wintering grounds south of the U.S. /Mexico border than here
in the U.S.; the ink is barely dry on their visas before they
head home.
As the month progresses, we see other species of birds moving
southward. Swirling pods of vultures or red-tailed hawks form
great kettles, something Edwin Way Teale once described as
like a man walking slowly down the steps of a rapidly
rising escalator. The birds are in constant motion,
wings held aloft as they soar upwards on warm thermals.
These and other raptors rely upon the winds to help them cover
hundreds of miles in a day with little effort expanded on
their part. Take a moment and sit on the edge of Bull Canyon
in the La Sals or Gold Knob and watch the skies. Though you
may not see hundreds of migrant raptors passing your point,
you will see determined kestrels, soaring sharpies or gliding
redtails heading south.
Perhaps youll observe hundreds of swifts and swallows
catching their dinner on the run as they too move southward.
Long ago, observers thought that swallows hibernated in the
mud or flew to the moon to avoid the long, cold winter season.
Those early watchers were astute - at least they realized
that the birds had left, gone somewhere else.
But it is not the cold that these birds are avoiding. Rather,
it is the shortage of food, insects primarily, that drive
these birds to other places. If there were sufficient food
resources available, perhaps that hummingbird would rather
stick out the cold than undertake a perilous thousand-mile
journey. That is why there are more insect eating migrants
than there are seed eating migrants.
Though
hummingbirds and robins migrate in the day, think of completing
this task in the darkness, with daytime stopovers to rest
and feed. Using the position of the stars, sun and moon, along
with other sensations such as weak magnetic fields, odors,
polarized light, barometric pressure and low frequency sound
waves, these nighttime migrants pass overhead while we are
deep in slumber. I often wonder how these birds react when
they descend from the heavens to their self-appointed stop
over location and that area is gone. Paved over or clear-cut
or ravaged by a wildfire. Do they come to a crash landing,
stand there stunned and perplexed or do they register the
change and just move on? Certainly, the birds have had to
make adjustments to Ice Ages and major catastrophic changes
in their pasts, but todays changes come much faster
and seem to be of greater intensity. Just how these changes
will affect the birds is anyones guess, but Id
have to say that the odds of getting a tax refund are better.
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