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Courtesy
International Crane Foundation (www.savingcranes.org)
A Miocene crane fossil, thought to be about 10 million years old, was
found in Nebraska and is structurally identical to the modern sandhill
crane, making it the oldest known bird species still surviving.
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The sound was amazing. Thousands of wild bird voices
clamoring across frosty March fields.
While They flew in wide V's or danced in pairs, leaping
high on long legs. Many grazed, probing their bills into the mud, but
the huge flock kept up a constant trumpeting discourse.
These were the famous sandhill cranes, and last March,
I stood with hundreds of admiring people celebrating the crane's brief
spring sojourn in the San Luis Valley during the Monte Vista Crane Festival.
The sandhill crane, Grus canadensis, is the most abundant
of the world's cranes and one of the most ancient of all birds. Each
stands 45 inches tall and is grey, except for a dark red patch on the
forehead.
In flight, they extend their necks straight out, streamlined
with their long legs behind. Sandhills eat seeds, grains and small insects
and animals. They depend on wetlands, spending the night standing in
shallow water and building low platform nests in marshes for protection
from predators.
Cranes mate for life, producing one or two eggs annually.
Both parents take turns on the nest, painting their feathers with mud
for camouflage. They guard their nesting territories in the marshes of
the northern U.S. and Canada.
Chicks hatch one month after the eggs are laid, but
one chick is always a day or so older. If food is scarce, usually only
the oldest will survive to fly south and then north again in the spring.
Chicks learn from their parents for almost a year. Then
the parents will drive chicks away to flock with other young birds and
claim a nesting territory until they are ready to mate at age 4.
Cranes migrating along the Rocky Mountain flyway have
been visiting the shallow ponds of the San Luis Valley for millennia.
These sandhills nest in the Yellowstone area and winter in the Chihuahuan
desert of New Mexico and Mexico.
Flying north in the spring, they follow the Rio Grande
Valley, using the wetlands near Monte Vista as a staging area for a few
weeks to feed and build their energy reserves before the flight north
to summer nesting areas. During that time, they dance with their mates
to reinforce the bond.
Throughout the years, valley marshes have been drained
for farming and development, and crane habitat has disappeared. As a
result, the Monte Vista National Wildlife Refuge has been preserving
wetlands and providing cornfields for food.
The Monte Vista Crane Festival, March 9-11, is a marvelous
way to see these fascinating birds. And while we saw a variety of ducks
and watched a pair of great horned owls guarding a nest, the sandhills
are the stars of the show.
And once you have heard their voices you will never
forget that thrilling, haunting sound.
For more about the Monte Vista Crane Festival, visit www.cranefest.com.
Gail Grossman is retired from the Durango Nature
Studies board of directors in 2006 after six years of dedicated service.
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