One of the world’s greatest migrations pauses every March in one humble place, central Nebraska’s flat landscape full of cornfields, located in the middle of the United States.
While people may fly over or drive through the area at high speeds on Interstate Highway 80, sandhill cranes stop to appreciate the adjacent wide, braided channels of the shallow Platte River to roost and feed.
Last year, a record 1 million of the lanky, playful birds — about 85 percent of the world’s population — stopped on their northward migration.
In recent decades, more visitors have discovered the migration, looking up from car windshields as wave after wave of cranes fill the sky for six or more weeks, or crowd into river blinds — a structure that allows bird watchers to remain hidden while peering through camera lenses and binoculars in awe.
Scientists here say there is only one other migration as concentrated and spectacular in the world: the wildebeest migration in Africa.
Getting close to the cranes
On a morning in mid-March, a ritual unfolds. Dozens of tourists gather at 5:45 a.m. at Audubon’s Rowe Sanctuary here and walk arm-in-arm down a dark trail, carefully feeling their way with their feet. As the group gets closer to the riverside blind, they are hit with sound. It’s described as a loud, but somehow gentle croak, chortle or rattle.
It’s a sound that travels far and right into the hearts of those tiptoeing into the blind.
Neseem Munshi said the calls go “deep into my soul.”
“The sound that they make is such a moving, ancient sound. If I could just live and breathe that sound, I would be a very happy person,” said Munshi, who was raised in Kenya and today lives in nearby Colorado.
Hundreds of foreign travelers from 66 countries viewed the migration last year. Overall, the 50,000 tourists who come to this rural state, located nearly midway between the East and West U.S. coasts, spend an estimated $14.3 million, buoying the local economy, a 2017 tourism survey states.
And the cranes, among the oldest known bird species, put on quite a show.
The sandhill crane is a 1.2-meter-tall (4-foot-tall) bird with long legs, neck and beak, and a wingspan of 2.1 meters (7 feet). Their soft grey plumage is sometimes spotted with rust colors, but its signature is the bright red patch on the top of its head. That, and it’s playful hopping, or dancing, which viewers hope to see once the sun rises.
The migration occurs here as the birds make their way from wintering grounds, fanned out in Mexico and in Southern U.S. states, all pointing toward a thin 130-kilometer-wide (80-mile-wide) center of the hourglass between the cities of Kearney and Grand Island, Nebraska, before fanning out again north toward Canada.
‘Almost obliterate the sun’
The birds hang around at this staging location, coming in waves, at times as many as 400,000 in one day, feeding in the nearby stubbles of cornfields and wet meadows, where they get energy from leftover grain and protein from critters in the soggy ground.
“They get up in the air and almost obliterate the sun,” said Jim Jewell, who joined the group in a blind. It was his first time, even though he lives in nearby Kearney. “It’s something you see every day but never get used to it.”
Many tourists start the prior afternoon, driving the gravel roads near the river where the birds are feeding. Cars are stopped with binoculars jutting out the open windows. Near sunset, they travel to blinds or river bridges, where platforms are erected to watch the cranes come into the river to roost in water, which is a social and protective behavior. The water acts as a sound warning in the dark to protect them from chasing predators, such as coyotes.
The cranes glide from the sky, not in any strict pattern of leaders and followers like the estimated 9 million ducks and geese that also fill the skies here, but haphazardly descend to the river, floating down with their long legs dangling like landing gear.
“The best description I’ve read is like a dandelion seed falling gently,” said Chris Helzer, science director of the Nature Conservancy in Nebraska, which also gives blind tours to members and donors.
As it grows dark, the river is filled with a roar of chattering sound.
Helzer said climate change may have caused a shift in behavior among the cranes, but the data on the precise cause isn’t in.
Some cranes are arriving earlier, the first in the early part of February, and more now are leaving after a shorter time here, heading to another staging area in North Dakota.
Stop on the way north
The cranes typically stay for two to three weeks, to feed and rest. They are leaving in worse condition, however, as waste grain has diminished because of better harvesting equipment or competition from the growing numbers of migrating snow geese. But the cranes are showing remarkable adaptation, and their population is increasing, experts say.
The principle ecological issue is the habitat and changing river. As more water is used for agriculture in Western states, the Platte dries up in summer. Trees then grow in the wide and shallow channel, which the cranes don’t like because they could be filled with predators like bald eagles.
The nonprofit Crane Trust is working on the issue by providing 5,300 acres of habitat in an area where only 2 percent of the lowland tallgrass prairie remains and bulldozing the trees from the river channel.
“We think locally but act globally,” said Crane Trust president Brice Krohn. “We want to lead by example for the betterment of the species.”
The trust also leads daily tours to blinds, where photographers flock to capture these photogenic birds in action. But visitors marvel at more than the birds.
“Everyone can’t believe the beautiful colors. The hues in the sky and the river so blue and, as Jane Goodall said, the ‘whiffs of smoke’ as they come from the sky and come into roost,” Krohn said.
Goodall, the famed expert on chimpanzees, has been coming to Nebraska to see the cranes every year since 2001, according to Crane Trust officials.
The culmination for many is the sunrise viewing, however, when people typically attached to mobile devices silently stand in the dark together and wait. As light comes to the river, the cranes begin tossing weeds or sticks in the air and hopping, bowing to each other, then leaping. They might even do-si-do to a neighbor.
Helzer compares it to square dancing, but most of the dancing is pair bonding. The cranes mate for life.
“You see the movement and the nervous energy through the flock,” he said. “You see them waking up after all night on the river; it’s gotta be cold. You see them hopping a bit. Then all the sudden they are jumping in full height and spreading their wings and the morning has started.”
Thousands of birds will later burst into flight, in a roar unlike anything outside a football stadium.
“It’s a very emotional experience for everybody,” Munshi said. “Some people cry.”
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