500,000 Cranes Are Headed for Nebraska in One of Earth’s Greatest Migrations
At the end of March, 80 percent of the world’s cranes will converge upon one 80-mile stretch of land
/https://tf-cmsv2-smithsonianmag-media.s3.amazonaws.com/filer/40/b4/40b41854-c79d-4e4d-99bb-81429d1a6266/01-sandhill-cranes-flight.jpg)
Nature got it right with the cranes. They have been around since the Eocene, which ended 34 million years ago. They are among the world’s oldest living birds and one of the planet’s most successful life-forms, having outlasted millions of species (99 percent of species that ever existed are now extinct). The particularly successful sandhill crane of North America has not changed appreciably in ten million years. There are 15 Gruidae species, and in all the human cultures that experience the birds, they are revered.
In my travels I have encountered cranes on three continents. Tibet, November 1995: Driving along the Yarlung River, we spot a flock of black-necked cranes in a marshy flat, but when we try to sneak closer on foot with our cameras, they see us from a long distance and, slowly lifting themselves up into the air on their enormous wings, take off. There are only 6,000 or so black-necks. These are making their way south, to spend the winter foraging on agricultural residue in Bhutan. Three hundred black-necks return each December to Phobjikha Valley, where in the morning and evening, as they take off to eat and dance and return for the night, they circle repeatedly around a monastery called Gangtey Gompa. The local Bhutanese believe them to be reincarnations of departed monks, and have for centuries performed elegant crane dances, tilting and sweeping long white wings attached to their arms. Cranes are the Bolshoi of animal dance. They dance at the drop of a hat, for all kinds of reasons, not just courtship.
Neolithic peoples in Turkey in 6500 B.C. imitated the dances of cranes as part of marriage rituals. Dance is one thing cranes are credited by many societies with giving us. Another is language, perhaps because they are so vocal and a single crane’s calls, amplified by its saxophone-shaped trachea—the windpipe in its long neck—can carry a mile. And unlike geese, with their disciplined, purposeful vees, cranes fly in loose, drifting, chimeric lines that are constantly, kaleidoscopically coming apart and forming, the ancient Greeks imagined, many letters. Crane hieroglyphs were applied to the Temples of Karnak 4,000 years ago.
In 1990 my wife and I were married in her village in southwestern Uganda. The festivities went on for three days, and all the while a couple of dozen gray-crowned cranes, with regal bonnets of sun-shot yellow feathers, were pecking and padding around in the adjacent savanna. The gray-crowned crane is my wife’s clan totem, so their presence was auspicious. Once common all over East Africa, this species is taking a terrible toll from local poachers who are selling them to the international pet trade. Only 30,000 gray-crowned cranes are left in all of Africa.
The sandhill cranes of North America are the most abundant crane species. Migrating sandhills come in three basic sizes—greater, lesser and the mid-size Canadian. I’ve seen the resident sandhills in Florida, three of them pecking for worms on a lawn outside Orlando, and several members of another resident population in Mississippi, which has just 25 breeding pairs. The Eastern population has rebounded dramatically from near extinction in the 1930s and is now up to more than 80,000. I saw a couple of big sandhills on the north bank of the St. Lawrence River in eastern Quebec, just above the mouth of the Saguenay River, a few summers ago.
Every year 400,000 to 600,000 sandhill cranes—80 percent of all the cranes on the planet—congregate along an 80-mile stretch of the central Platte River in Nebraska, to fatten up on waste grain in the empty cornfields in preparation for the journey to their Arctic and subarctic nesting grounds. This staging is one of the world’s great wildlife spectacles, on a par with the epic migrations of the wildebeest and the caribou. It takes place in three waves of four to five weeks each, beginning in mid-February and ending in mid-April, during which birds that arrive emaciated from wintering grounds in Texas, New Mexico, Arizona and Chihuahua, Mexico, gain 20 percent of their body weight.
It usually peaks in the last week of March, which was the case in 2013. Wildlife photographer extraordinaire Melissa Groo and I hit it just right.
***
Traveling west from Lincoln on I-80, we begin to see masses of the stately birds in the rows of corn stubble flickering by. Ranging in height from three to four feet, they are moving on black stiltlike legs (their “knees” are modified heels, so they actually walk on their toes), with their necks bent down, stabbing at the stubble with long daggerlike beaks, flipping cow pies, crunching up insects, snails, frogs and snakes. The adults have bare red foreheads that expand when they are worked up and compact feathers covering their ovoid torsos—except for their bustles, the loosely stacked tips of their wing feathers that extend past the short tail and flare up when they are agitated.
Not only the cranes, but some 20 million other migrating birds belonging to 300 or so species stop over on the Platte, including 280 of the remaining whooping cranes, 90 percent of the white-fronted geese that ply the midcontinent, thousands of endangered piping plovers, 30 percent of the northern pintails, 50 percent of the mallards, as well as bald eagles and some two million snow geese. Soon after we travel under Kearney’s Gateway (to the Great Plains) Arch, we pass a depression—an old borrow pit—smothered with maybe 20,000 milling snow geese, like a blanket of snow. The geese come earlier than the cranes and clean out many of the cornfields near the river, but there is plenty of waste grain in the central Platte valley to go around. Michael Forsberg, a Lincoln-based wildlife photographer, calls this stretch of the Platte “the pinch in the hourglass” for all these converging northbound migrants.
To Forsberg, the sandhill crane is the ambassador of the plains. Some 70,000 crane watchers flock to the Platte annually, last year from every state in the union and 47 foreign countries, injecting $11 million into the local economy. People tend to think of Nebraska as a fly-over or drive-through state, he says, but there is incredible beauty, only it’s subtle—except when the cranes are here.
Crane-watching consists mainly of taking in three activities: when they wake up and take off from the sandbars on the rivers, when they come back to them to roost, and during the day when they are out foraging in the cornfields and doing their dances. The most popular place to see the sandhills on the river is the National Audubon Society’s Rowe Sanctuary in Gibbon, just outside Fort Kearney. One morning at 5, I tiptoe into a viewers’ blind at Rowe with a score of other tourists and we station ourselves and our cameras at its little windows. No flash or LED lights are allowed. It is bitter cold, ten degrees with the windchill. As day begins to break, we see that a 100-foot channel of the river, with shards of ice on its surface, is gliding silently by right below us. Its pebbly bottom is only a foot or two down. Across the channel is a sandbar on which the faint gray forms of several thousand lesser sandhills, still sleeping on their feet with heads tucked under a wing, become increasingly apparent. They are headed to the Kuskokwim Delta in the Yukon and western Alaska, some all the way to Chukotka, in eastern Siberia. The smaller the crane, the farther it flies to its nesting grounds, and the shorter and more needle-line its beak.
The midcontinental sandhill population has four “breeding affiliations,” two of which overlap. This was discovered by Gary Krapu, a wildlife biologist with the United States Geological Survey, who netted and tagged 153 sandhills on different stretches of the Platte and satellite-tracked them from l998 to 2003. Most cranes take over the same section of river each year. This is not unique to cranes. We have a yellow-bellied sapsucker that returns to our cabin in the Adirondacks each spring from wherever in Central America or the Caribbean it wintered and drives us crazy drilling on the roof to attract a mate. The bigger cranes, from the other affiliations, have staked out the sandbars downstream, all the way to Wood River. Some are headed to Hudson Bay and the Canadian boreal, with its mazes of bogs and muskeg to nest in.
George Archibald, the co-founder of the International Crane Foundation, thinks the first ancestral cranes were likely from the New World. The crane’s closest relative is the limpkin, a New World tropical wading bird. Crowned cranes, the oldest lineage of Gruidae, radiated to Africa, where the only two species survive. Fifteen-million-year-old crowned crane eggs and a skeleton have been found in northeastern Nebraska. According to the fossil record, the sandhill migration has been going on for millions of years. “During the ice ages their range was constricted, and as the ice retreated to the north they developed these long migrations,” explains Archibald. “They followed the ice north. Nebraska is at the southern edge of the last glaciation. What they may have been doing during previous interglacials there is no way of knowing.” To this day, cranes are often described as birds that “follow the edge of winter.”
The cranes on the sandbar begin to stir and purr contentedly. They sound like a chorus of drawn-out rolled French r’s, like their French name, grue, and their English one, “crane,” from the Proto-Indo-European gerh, meaning to cry hoarsely. Some of the cranes step out into the water.
Margery Nicolson, an elderly woman who is volunteering as a docent, whispers to me, “Around the bend, it’s packed solid with cranes for a mile upriver. The white-cheeks are the adults.” Nicolson comes every year from Pacific Palisades in Los Angeles to be with the cranes. The visitor center is named for her late husband. Another docent, volunteering from Tucson, whispers to a couple taking in their first cranes, “They start coming on Valentine’s Day and leave in time to pay their taxes.”
The murmur of contentment, the fricative purr, spreads among the cranes and grows louder. Some of them begin to flap their wings, whose underside tips are black, and a contagious frisson of flapping and rolled r’s ripples through the flock, particularly along its edges, where the hormonally pumped adolescent colts are. (For some reason crane nomenclature is borrowed from horse terms. A mother crane is called a mare, the dads are roans. The terminology sounds like it was created out West.) A male starts braying, likely calling for its mate. The collective purr is punctuated by unison calls between bonded pairs, during which the male points his bill straight up to the sky and the usually shorter female points hers at a 45-degree angle and gets in twice as many (and higher-pitched) calls as he does.
When the sun hits the flock and turns it gold, they all take off, peeling out in extended-family groups of 15 to 40, fanning out in every direction—except for scattered maverick late risers and one that Nicolson picks up in her binoculars that is lying down. “It must be injured,” she whispers. “That guy’s a goner, I’m afraid.” Two bald eagles are perched in a cottonwood tree a few hundred yards upstream. They will not fail to spot the injured bird and make quick work of him.
A few small groups return to the sandbar, floating down with their open wings cupping the air like parachutes and their landing gear (legs dangling down) deployed. The deafening hysterical chain reaction of thousands of them taking to the sky at once makes it clear that these are highly social, gregarious birds who take cues from one another.
Bill Taddicken, Rowe’s director, tells me that the Platte has lost 80 percent of its width and 70 percent of its flow to hundreds of diversions—including eight major dams on the North Platte and 20 on the South Platte (the two forks meet upstream at North Platte)—that siphon it off for municipal and agricultural use. Fifty miles of crane staging habitat has been lost to dams and “reclamation”; only the 80 miles from Overton to Chapman remain. In spring flood the Platte used to be two miles wide in places and the floodwaters used to scour the vegetation off the sandbars, but the spring runoff is barely a dribble now. Rowe staffers go out on the bars with tractors and disk the overgrowth, including acres of solid purple loosestrife and phragmites that aren’t even native.
Downstream is the Wood River, where the Crane Trust, founded in l978 with federal money to keep the whooping crane going, has 5,000 acres, and where tens of thousands of greater and Canadian sandhills, mainly—bigger birds in bigger numbers—are already slumbering on the sandbars. At the crack of dawn Melissa and I are in the trust’s main viewing blind, which overlooks a series of large sandbars on which 15,000 or 20,000 close-packed inert sandhills are standing. Their bodies are glazed with a white film of frost. We feel that we are in the presence of something extraordinary, the abundance that was once everywhere. What is left in the bird world that’s anything like this? The pink flamingos on Kenya’s Lake Nakuru, some years in the millions, the South American flamingo species that pack several lakes in the Andes. I am filled with a mixture of awe, nostalgia, gratitude and remorse.
Around the bend there’s another congregation of 40,000 to 80,000 cranes, says a big genial guy in the blind named Brad Mellema, former director of both the Rowe and the Crane Trust nature center and now director of the Grand Island visitors bureau. What do you call these huge assemblages? In the Middle Ages there was a murder of crows, and a sedge or siege of cranes or herons. “We say a flock or a bunch,” Mellema explains.
Paul Johnsgard, the 82-year-old éminence grise of popular writing about the cranes, who has published more than 60 books, calls the staging a “congruence,” punning on the crane family’s Latin name (Gruidae). Melissa suggests “confluence:” the four affiliations converging on the Platte. Congregation, conclave, convention, hoedown, powwow, shindig, gathering of the clans, ornithological Burning Man. Aldo Leopold, who was instrumental in getting the confab on the Platte protected, puts it in his lyrical “Marshland Elegy,” “Our ability to perceive quality in nature begins, as in art, with the pretty. It expands through successive stages of the beautiful to values as yet uncaptured by language. The quality of cranes lies, I think, in this higher gamut, as yet beyond the reach of words.”
“Our birds come earlier than Rowe’s,” Mellema continues. “These particular ones we know from radio telemetry are from the Gulf Coast and headed for Hudson Bay. The ones at Rowe come from the Texas Panhandle and go up to Fairbanks. Hear the juveniles trilling like cheap gym whistles? Their voices haven’t changed yet. These birds are contented. They’ve been eating for two weeks.” The purr of contentment, which Mellema describes as a chortle and “the sound of the Pleistocene,” never dies down completely during the night, and as the sun hits the birds and brings them to life, the 10,000-bird chorus builds and there is antiphonal quaking back and forth between different parts of the mob. These birds are in no hurry to take off. At 10:30 most of them are still there, but contagious dancing is going on around the edges. Some have moved out into the water, so they can alert the others if an eagle or coyote approaches, Mellema surmises. “There’s always a sentinel. A sandbar is like a hallway in junior high school. Multigenerations come back year after year, and it’s entirely learned. The juveniles play the singles scene.” Archibald says that even if colts separate from their parents here, they return to their natal area rather than being led astray by other cranes. Like elephants, cranes have excellent memories and wear their hearts on their sleeves. Like us, they mate for life but sometimes cheat and divorce. There’s a delightful, moving YouTube video of Archibald dancing with a whooper to stimulate egg production. I know a striking six-foot woman who dances like a crane but has never seen one. We are all on an evolutionary continuum. “I am the walrus,” the Beatles sang, “I am he as you are he as you are me.”
A family of six takes off. Mellema points out how the rhythm of their wingbeats is different from that of geese, which is up and down, one two, one two, same beat, while cranes’ downbeat is slower, twice as long as their upbeat, as they force the air down with their long, powerful wings.
***
Melissa and I drive from the trust down South Alda Road to the Alda Bridge over the Platte, a magical stretch of road. There is an observation deck at the river with a sign that explains how the Platte Valley formed four immigrant routes, the Oregon, California, Mormon and Bozeman trails. “Nebraska” comes from the Omaha name for the river, Flat Water.
I go down to the river and sit under a cottonwood listening to the raucous, exultant, quaking din downstream of two huge flocks, neither of which is visible. They sound like two baseball stadiums erupting when a ball is hit out of the park, and the roars are answering each other antiphonally. Even in Kearney when I step out of the Best Western, the sky is filled with crane calls. They drown out the whoosh and whine of semis on the Interstate 200 yards away. For two months every year cranes own the soundscape. Archibald says 16 separate vocalizations have been recognized, and they mean different things in different situations and intonations, depending on whether they are made once or several times. So sandhills definitely have a language.
***
Melissa and I drive into an area of nothing but cornfields. The gently rolling landscape is, as Melissa puts it, “lousy with cranes”—flocks of 50 to 200 or more variously known as creches, survival groups and extended families. These birds are skittish. The moment we pull up to one group, however slowly and quietly, they all take off. Sandhills are protected in Nebraska, but hunted in the majority of the U.S. and Mexican states and Canadian provinces they fly in. An estimated 33,000 a year are shot by hunters, who extol the cranes as “the rib-eye of the sky.” The birds seem to have a warning call that says, as one cranewatcher parses it, “Humans! Let’s get out of here!” Some of the groups just become agitated, and a few cranes start dancing. This is what Archibald calls “ambivalent behavior. They’re nervous, but not enough to fly, so they do something, anything.”
“I wish they knew they were safe,” Melissa moans. As in, Whew. I crossed the state line. No one can shoot us.
In the Nicolson Center at the Rowe Sanctuary, I had picked up the pocket-size Sandhill Crane Display Dictionary, by George Happ and Christy Yuncker-Happ, a must-have craniac resource on the basic moves of crane ballet. We tick them off as we see them performed by the birds that settle down and more or less accept our presence. Object-tossing, usually a corncob or a stick, is common. There’s the tall-investigative stance, when there is no threat but the bird is vigilant. Within a group of foraging cranes several usually assume it. They are the sentinels. If there is a visible threat, the bird goes into tall-alert, staring intently. Then intent-to-fly, leaning like pointers. We see 20 of them doing this, following a large bird that is moving through the rest of the pack.
Behind a scrim of cedar on a rocky point jutting into one field, serious dancing is going on. Dancing facilitates pair-bonding and ritually confirms decades-old bonds, allows rivals to assess each other and to ritually dissipate aggression. Pre-adult cranes practice dancing for three years before they mate. Parents educate their chicks by dancing with them. The bow is done after mating and as a threat when landing in a crowd of cranes. I wonder if the Japanese got their custom of bowing to each other from the cranes.
We don’t see the cloacal kiss, the actual deed, which takes only a few seconds, but we do see precopulatory behavior, a female facing away from the male and flattening her back and fanning out her wings to form a slanting ramp that he can mount, and the male approaching her in parade march. But they don’t do it. Maybe this is practice. Mating does happen on the Platte, and at the wintering grounds, Archibald says, though most of the courtship and copulation happen in the summer breeding grounds.
We see a confrontational crouch-threat, a ground-stab, which means look at me and let’s dance. And at afternoon’s end, 20 or 30 birds dance up a storm on a ridge against the sky.
I asked Archibald why the whooper has to be danced into egg production, and he said the presence of the mate you are paired to is very important. The two of you have to dance for a month or two, two, three times a day as reinforcement, before anything happens.
“The chemistry of attraction is as mysterious with cranes as it is with humans,” Brad Mellema told me. “Size doesn’t seem to matter. A pint-size male can yank a big female’s chain.” Leading scientists think the female has a gland on her back that emits seductive pheromones if she is receptive to a male’s advances.
Karine Gil-Weir, who was the Crane Trust’s population ecologist for five years, tells me from her home in Texas that she once saw a bonded pair of sandhills touching bills, kissing, which “has never been reported, and I never saw it again, but I saw a painting of two doing it at the Stuhr Museum in Grand Island,” she says. “The rituals are symbols of how to keep a family strong.”
Allison Hedge Coke, a poet of Cherokee, Huron, métis and European descent, has been doing fascinating research on Native American crane clans. They were responsible for keeping the history of the people. The hieroglyphs you see at Petroglyph National Monument, for instance, across the Rio Grande from Albuquerque, look like chicken-scratch, but they are actually crane-scratch. The Hopi had a crane clan; the Mojave and Anishinaabe-Ojibwe still do.
In the evening I go out to the Nature Conservancy’s blind, upstream from the Alda Bridge, with Hedge Coke and a tall, regal Omaha poet named Renee Sans Souci and her four kids. Hedge Coke tells us to cover our heads and to walk in a weaving line, which she does and we fall in behind her, so as to be respectful and not spook the cranes. Soon we are in a non-European ritual space, doing our own dance. This is the native way, how the children are taught to honor the cranes.
A lot of the old crane knowledge and animism have been lost, casualties of Manifest Destiny and the European colonizers’ imposing their religion. Hedge Coke calls herself a cultural reclamationist. “The Pawnee lived on the Platte but were forced to move down to Oklahoma in the years following the Homestead Act. The Pawnee in this region had secret societies connected with the belief in supernatural animals. I am trying to find out their insights into the cranes.”
Much of the native dancing in the flyway is inspired by cranes. The Choctaw wear a white crane feather on their baseball caps to indicate ability. The Lakota wear a red adornment called a pesa that is like the forehead of a sandhill. Cranes are guardian birds, keepers of knowledge all over the world, and this is the epicenter.
“Listen,” she whispers, “a location call. The cranes behind the cottonwoods across the river are calling to their scout, Where are you?, asking if they can approach, and now the scout is going to give the OK call, and the cranes are going to start coming in.” The arrival is carried out with military precision. Once the all-clear has been given, groups start flying in from every direction and floating down on the sandbar on gossamer wings until there are so many we can’t even see the sand anymore.
Karine Gil-Weir told me, “This gathering is getting more problematic every year because of climate change, extreme weather, competition with snow geese and drought in the south.” This year 5,000 sandhills did not return to their wintering grounds but hunkered down on Mormon Island, on the Crane Trust’s property. If the drought and heat waves in the heartland continue, more will undoubtedly join them. But will the midcontinental sandhills become totally residential on the Platte like the Florida and Mississippi sandhills, or like the Canada geese, 60 percent of which no longer migrate? Archibald doesn’t think so. There’s not enough shallow wetlands on the Platte for them to breed in, and global warming is also increasing the length of time they can stay at their nesting grounds in the north from the 40 to 50 days they have to grow their fist-size chicks to full-size, flight-ready birds (one of the fastest growth spurts in the animal kingdom) and is giving their breeding season more flexibility. Archibald thinks sandhills are starting to stay on the Platte because of conditions being better in the north. “All over the world birds that used to winter farther south are wintering farther north due to global warming. Eurasian cranes that used to winter in Spain now winter in the north of France. These central-flyway sandhills will still have to go north because they need aquatic food with proper protein to raise young. And once fields are plowed and replanted in the spring, the ones that stay are going to be in trouble,” Archibald said. “I think the staging on the Platte will continue. However the Platte is almost dead. The whole environment is manipulated. But the sandhills seem to be doing fine. Their population has been stable for the last 10 to 15 years.”
And how many things can that be said about? But global warming is also melting the glaciers in the Rockies where the Platte rises, and in 2012 the tornado season arrived three months early; in March there was a cluster of monster tornadoes only 100 miles west of the staging. In l990 a flock was shredded by a twister into what looked to one witness like “bits of newsprint.” But the cranes are highly adaptable. They wouldn’t have lasted this long if they weren’t. I imagine they will learn to give tornadoes an even wider berth than they do humans, if they haven’t already.
/https://tf-cmsv2-smithsonianmag-media.s3.amazonaws.com/accounts/headshot/Shoumatoff.jpg)