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To stand by the Platte River near sunset in early spring, is to witness one of natures most extraordinary scenes. All around, the air is filled with the soft warbling call of the Sandhill Crane. In all directions, thousands of cranes are returning to roost in the safety of the river. Bird after bird flair magnificent wings, and parachute gracefully to earth. A pageant made even more dramatic when framed against a flaming prairie sunset.
Sandhill Cranes returning to roost.
Since long before there was a Platte river, the cranes have returned to this place. The oldest known fossil, undeniably that of a Sandhill Crane, is over two million years old. The Platte River, dating back a mere ten thousand years, is but a youngster in geologic terms. The fossil of a crane ancestor, found in central Nebraska, has been dated to between nine and ten million years of age, making the Sandhill Crane one of the oldest bird species on earth.
When cranes began visiting what is now central Nebraska, prehistoric camels, rhinos, and elephants roamed a landscape resembling the east African savannas. The crane survived the extinction of these animals, and into an age dominated by humans. This, greatest of all transitions, has taken place in less than two centuries.
Of the six Sandhill Crane subspecies, three are migratory. All migrating subspecies are represented in Nebraska each spring. The most common of the migrating Cranes is the Lesser Sandhill. Although not a small bird by any means, the lesser Sandhill Crane is the smallest of the group. An adult male can stand four feet tall and weigh over twelve pounds. The sexes look alike, with males being slightly larger. The adult bird is primarily gray in color, with a crimson forehead and white cheeks. The undersides of juvenile cranes are a more reddish brown. The cranes legs are long and dark, and unlike smaller birds, their legs trail behind them in flight. When in flight, the cranes keep their necks straight forward. Their long necks, trailing legs and a six foot wing span, make an impressive sight. Cranes are powerful fliers, able to stay aloft for hours. Like raptors and vultures, the Cranes broad wing span, makes them experts at riding thermals. Cranes ride spiraling thermals upwards to altitudes of two thousand feet or more. They glide northward, losing altitude, until reaching the next thermal, and then repeat the process. This highly efficient method, allows the migrating birds to travel as far as five hundred miles in a single hop.
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Sandhill Cranes in flight.
Cranes spend winters in Texas, Louisiana, Mexico, and New Mexico. In late February they begin their great northward journey. Most of North Americas migrating cranes travel via the central flyway. Cranes begin arriving along the Platte only one to two days after departing their winter quarters. Along the Platte, crane numbers peak in late March. The Platte River in central Nebraska is the idea place to take a break during their migration. The broad, shallow Platte affords safety. Thousands of acres of farm fields provide food. Cranes remain along the river, feeding and resting, until about the second week in April, when a mass exodus occurs. An individual bird spends, on average, twenty-nine days in Nebraska. During this layover, they will pack on as much as two pounds of fat.
Of the three migrating subspecies, the Greater Sandhill crane nests in Western Minnesota, and the Interlake region north of Winnipeg Manitoba. The Canadian subspecies nests all across central Canada from Hudsons bay to the Rocky Mountains. As many as eighty thousand Lesser Sandhill cranes journey as far as eastern Siberia, while the rest nest in Alaska, and the Canadian high artic. The body fat, acquired during their Platte River layover, make these prodigious journeys possible. The Platte River rest period is one of the few times a species has benefited from human intrusion. Cranes are estimated to consume as much as sixteen hundred tons of grain missed during fall harvest. This grain would otherwise be lost, or come up as unwanted volunteer vegetation in spring. Its a rare win-win situation for agriculture and wildlife. Before corn and other crops appeared, cranes fed on starchy tubers produced by a variety of aquatic plants. One such plant species was Nuts Edge, which was once abundant in the widespread wetlands bordering the Platte before European settlement.
Cranes nest on the ground, building nests by scraping available vegetation into mounds. Normally two eggs are laid but, because cranes do not fly until about ten weeks of age, it is rare for both chicks to survive. Nesting cranes and their eggs are subject to predation from scavengers, raccoons, and raptors. Adult cranes are preyed on by all manner of preditors from wolves to owls. Chicks remain with their parents, until the following spring. If the observer pays attention, three bird groups are easily identified. Cranes have been known to live twenty-five years in the wild. Perhaps, because of their long lifespan, cranes do not attain sexual maturity until three to five years of age.
Observing the mating ritual of the Sandhill Crane is one of the most enchanting aspects of their Nebraska lay over. The dance of the Sandhill Crane involves an elaborate display of bowing, running, and jumping high in the air with outstretched wings. Cranes will occasionally pick up sticks or other available items, throwing them repeatedly. During mating, pairs belt out duets, engaging in a complex behavior known as unison calling. Its thought these behaviors help establish, and strengthen pair bonding. Although cranes normally mate for life, birds that have lost a mate will mate again.
  
The "dance" of the Sandhill Crane.
Though the Sandhill Crane is not threatened as a species, the non-migratory southern subspecies are becoming increasingly rare. The non-migratory population has far less control over their nesting habitat, thus leaving themselves more vulernable to predation and human behavior. Good conservation practices have helped the Greater Sandhill Crane to rebound from as few as a thousand birds seventy years ago, to about a hundred thousand today.
You are cordially invited to visit me at, highplainsphotosandframes.com, where you can view the many crane photos posted there. About six weeks from this writing, the cranes will once again be returning to the Platte. The Nikon and I will be there, waiting to welcome them back. A day on the Platte River, photographing cranes, is a very good day indeed.
Patrick Simons
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