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One
of my earliest memories of experiencing the wonder
of migration was when I was eighteen years old, abd
standing on a beach by myself. I was looking out at
the Pacific Ocean watching thousands of birds fly
along the horizon. I watched for over an hour as
the birds stitched the
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water to the sky as they flew
in a single line. I had never seen anything like
this before and many years later I realized that I
had seen shearwaters in migration.
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Migration is the perfect
vehicle to explore the study of birds. Through
migration we become aware of navigational skills,
aerodynamic feats, logistics of speciation, the
competition with humans for resources and many
other factors.
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It is a study of the unique
nature of each species. The female Yellow-bellied
Sapsucker migrates
further south than the male; in some pelagic
species the young are born with genetic maps, and
other species have a window of time that they learn
the stars in the sky that they will use to migrate.
We learn of remarkable navigation skills such as
the shearwaters that are taken from their nest by
well-meaning researchers and flown to places that
they as a species have never visited, and yet they
find their way home.
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It is a study of how birds
utilize different habitats for different seasons.
The Common
Loon feeds
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in the ocean during the
winter and migrates east and raises its young in
fresh water. The Long-billed Curlew uses its long
legs to feed along the shore during the winter and
during the spring
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uses its legs to help it hunt
in the tall grass prairie.
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It is a study of how birds
know. Some species operate with innate knowledge,
others with learned knowledge, and others with
knowledge that is the combination of innate
knowledge improved with what the bird learns from
experience. Some species of ducks learn about
migration from their parents; others don't. The
young of the Long-billed
Dowitcher migrates
two weeks earlier than their parents.
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It is a study of politics as
some people try to save land and others try to
profit from it. On the outer banks of Alabama there
is a struggle to hold on to the land so that
thousands of migrating birds flying over the Gulf
of Mexico can have a place to land and feed when
they need it most; but other people want to take
the land and make it into vacation homes.
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It is a study of speciation
as we watch the varieties of migration for the
different races of White-crowned
Sparrows. In
California it is difficult to make a blanket
statement about whether or not
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the White-crowned Sparrow
migrates.A couple of the races do and a couple of
the races don't. And at least one race moves from a
lower altitude in California, to a higher location
in the same state to breed.
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It is a study of humans
trying to understand their responsibility as they
participate in the natural heritage. John James
Audubon witnessed and recorded the killing of
25,000 Golden
Plovers by a small
set of hunters in a single day.
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We have created a refuge
system to support the population of
Snow
Geese and now their
population has exceeded the carrying capacity of
the tundra where they breed. It is estimated that
here are now two million excess Snow
Geese.
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It is a study of the citizen
birder who gathers data of the arrival and
departure dates of individual species and
contributes that data to the researchers so they
can continue their work. The citizen birder also
participates when they become a licensed
bird-bander or assists a bird-bander and
participates in gathering data on migration.
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Most of the wetlands are
gone. Most of the prairie is gone. Most of the
forests are gone. We have taken the land that
supports migration and enables breeding.
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Not only are we changing the
climate which is upsetting the synchronicity
between migrating birds and their food items, but
we are eliminating migration and replacing it with
Canada
Geese. The Canada
Goose has stopped migrating, and instead has become
an unsustainable population and an embarrassing
nuisance.
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We are harvesting at an
unprecedented intensity, materials that we
previously only minimally harvested such as
Horseshoe Crabs. In our own backyard the
rufa race of the Red
Knot has been
drastically affected by the sudden decrease of
Horseshoe Crabs which it would feed upon during
their migration north. It is estimated that this
race of the Red Knot could become extinct by 2011.
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Migration is a natural
phenomenon that can produce wonder and amazement
and studying it produces valuable knowledge. We as
a nation have to learn to value that knowledge and
act on what it is telling us.
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