Timeless Birds, Changing Times
by Howard Youth
In December 1985, I was a college student driving across the country in search of birds and myself. Several sleep-deprived days out from the University of Maryland, I found myself alone on the Texas Gulf Coast, atop an observation tower in Aransas National Wildlife Refuge. I had not merely wandered to this spot. I had a specific goal: to see the world’s rarest crane.
|Sandhill cranes are the most numerous of the 15 crane species. (Jessie Cohen, NZP)|
As mid-morning sunlight warmed the ground and sent up invisible thermal air currents, a long-necked gray bird rose above the grasses, flapped in circles, then soared overhead. I was thrilled to see my first sandhill crane (Grus canadensis), but also a bit disappointed. After all, during winter, Aransas was the only place on the planet where you could see endangered whooping cranes (G. americana). I had read that with much luck, visitors sometimes saw whoopers from the tower. After several hours of watching, though, I was convinced I would not be one of the few.
Then, my luck took a good turn. A U.S. Fish and Wildlife Service (USFWS) pickup truck pulled up, driven by Tom Stehn. Stehn, a refuge biologist, was the person in charge of censusing wintering whooping cranes. I asked if he thought I had a fighting chance of seeing these birds if I remained at the tower. “No,” said Stehn, “but hop in my truck. Just about all I can guarantee you is a whooping crane.” We rumbled down an off-limits track through yucca-studded grassland, and in just a few minutes encountered creatures I’d always dreamed of seeing—a bobcat (Lynx rufus), a cottonmouth (Agkistrodon piscivorus), a white-tailed hawk (Buteo albicaudatus)…. Then Stehn parked the truck at a finger of land overlooking an expansive marsh. “There you are,” he said, pointing into the glassy water and marsh grass. “More than ten percent of the population is right over there.”
Through my spotting scope, I could see 15 immaculate white birds, their secondary flight feathers bunched into distinctive bustles over their rumps. Even at a distance they looked tall, and I could just barely make out the birds’ scarlet crowns and moustache stripes. That winter, Tom estimated the entire wild whooping crane population at a heartening 94 individuals.
From that memorable morning on, I have thought of cranes as the giant pandas of the bird world. While raptors, ducks and geese, toucans, and other birds may catch our eyes, cranes have star appeal. This charisma, combined with their dependence upon vanishing wetlands, makes them unwitting mascots for efforts to balance humanity’s growing needs with those of wildlife.
|The sarus crane is the tallest flying bird. (Jessie Cohen, NZP)|
But what exactly strikes us about cranes? Perhaps they remind us of ourselves. They stand up to six feet tall and walk upright on two long legs. Adult pairs often stay together until one member dies. Both male and female cranes are faithful parents: They work together to pluck vegetation and pile it up into their mound nest, incubate the eggs, and raise their young. Outside the breeding season, many cranes gather in large convention-like flocks.
Cranes are extremely communicative and, like many of us, go out of their way to make others take notice, in their case through elaborate, synchronized duets and dances. The dances often include bowing, leaping, running, wing-flapping, and a ceremonial tossing of grass or sticks. These rituals not only bring females and males together, they are likely important in young birds’ development, and help control aggression within flocks. Cranes live up to 20 to 30 years in the wild and breed slowly. While in most species young birds mature by two or three years of age, successful breeding usually takes place at four or five years old. Pairs of most crane species lay two eggs, but usually, with luck, they raise just one chick each year.
Lindberghs of the avian set, migratory cranes undertake dangerous international and transcontinental flights twice yearly between nesting and wintering grounds. Some common cranes (G. grus) fly over the Himalayas at heights up to nearly 30,000 feet. Some sandhill cranes undertake the longest crane migrations—leaving Siberian nesting grounds to reach as far east and south as northern Mexico. At one season or another, at least one of the world’s 15 crane species can be found in many parts of North America, Eurasia, Africa, and Australia. East Asia hosts the greatest crane diversity at eight species. North America has just two species, and, for reasons unknown, none ever reached South America.
Throughout history and in many cultures, Native American to Aborigine, Spanish to Japanese, storytellers, artists, performers, and language-makers kindled the human love of cranes.
Today, we often speak of cranes without even knowing it. We adorn Thanksgiving plates with and drink juice from berries of a wetland plant colonial settlers called craneberry. Although cranes sometimes eat these berries in the wild, the plant is likely named for its pinkish blossoms, which resemble the shape of a crane’s head and neck. Other flowers named for cranes are the geraniums. The name refers to a Greek word for crane geranos, for the crane-like appearance of their seed pods.
We crane our necks. We watch long-boomed cranes do construction work. In Spain, people watch grúas do the same work, while birders there enjoy watching grullas, or common cranes, as they migrate through the country and winter in its southern reaches.
In Asia, cranes are symbols of long life, happiness, good fortune, and fidelity. “From a conservation perspective, cranes symbolize wetlands, peace, and survival,” says George Archibald, co-founder and senior conservationist at the International Crane Foundation (ICF) in Baraboo, Wisconsin. Thirteen of the world’s 15 crane species depend upon wetlands for survival. Many are long-distance migrants whose very existence hinges on how well countries work together to ensure their well-being, not just at nesting grounds and at wintering sites, but also along migration corridors. These include political flashpoints such as the Demilitarized Zone between the Koreas (the DMZ), skies over Pakistan and Afghanistan, and imperiled wetlands in China that host virtually all Siberian cranes (G. leucogeranus), tall white birds that nest in Russia.
|The total population of red-crowned cranes, an endangered species, is about 2,400 birds. (Jessie Cohen, NZP)|
While by no means the only dramatic crane story, the whooping crane’s tale is also a classic case of endangered species struggle and recovery. Herculean cooperative efforts between Canadian and U.S. government and non-governmental organizations (NGOs)—and the dedication of individuals such as Tom Stehn and George Archibald—are helping to save a species that almost got away. But this drama is far from over.
Whooping cranes both nest and winter in expansive wetlands that provide them with a varied menu of aquatic insects, shrimp, crabs, fish, frogs, snakes, seeds, and berries. While never common, whooping cranes were once widespread, primarily nesting in prairie marshes of north-central United States and Canada and wintering in coastal wetlands along Atlantic and Gulf coasts and also inland at sites including tablelands of northeast Mexico. There was a nonmigratory population in Louisiana and perhaps one in Florida. But after a century of wetland losses, unregulated hunting, and egg-collecting across North America, whooper numbers tanked, hitting an all-time low of 22 birds by 1941. By 1950, the only birds left nested somewhere in Canada but wintered in southeast Texas in an area now mostly within the Aransas and Matagorda Island national wildlife refuges. The Canadian nesting grounds were not discovered until 1954, when the rare birds were found breeding in the wetlands of Wood Buffalo National Park, 2,400 miles from the Texas coast.
Adult whooping cranes teach their young to follow a narrow migration corridor, in the process running a twice-annual gauntlet, with dangers that include mist-shrouded power lines, some unscrupulous or uneducated hunters, bobcats, dogs, and other predators, and perilous weather. Despite these dangers, more than 80 percent of adults make it back and forth each year.
Having just one wild whooping crane population means that the bird’s fate is one hurricane, one large Gulf oil spill, or one disease outbreak away from disaster. Some climate models also predict that climate change may alter the Texas Gulf Coast and Aransas along with it, flooding the one fixed point to which all the wild birds head from Canada each year. That’s why conservationists have been toiling for decades to breed the cranes, and to set up satellite populations that provide insurance against loss of the last wild birds.
Starting in 1975, USFWS biologists began putting whooping crane eggs—first some wild ones then those of captive-bred pairs—into the nests of pairs in a wild flock of sandhill cranes that bred at Idaho’s Grays Lake National Wildlife Refuge but wintered at Bosque del Apache National Wildlife Refuge in New Mexico.
In 1989, 14 years and almost 300 whooping crane eggs later, the program was scrapped. As it turns out, sandhill-raised whooper chicks imprinted on their sandhill parents and flock mates, then sought sandhill mates rather than others of their own species. Conservationists went back to the drawing board. The result was two new and different strategies.
In 1993, a nonmigratory flock was started using captive-hatched whooping cranes translocated to central Florida. Today, this population tenuously holds on at just under 40 birds. So far, nine chicks have fledged in the wild from this effort. “The Florida population has faced drought, declining wetlands, and predation,” says Archibald. “We’re concerned that it won’t reproduce at a rate that will overcome mortality.”
A new effort to start a migratory flock got underway in 2001 with eight captive-hatched birds shipped to Wisconsin’s Necedah National Wildlife Refuge from the Patuxent Wildlife Research Center in Laurel, Maryland, where they were raised by white-costumed caretakers who attempted to minimize contact with them.
From Necedah, the birds were guided via ultralight aircraft (a costly but effective strategy highlighted using geese in the 1996 film Fly Away Home) on a 1,200-mile journey to Chassahowitzka National Wildlife Refuge in Florida. This route emulates the past migration pathways undertaken by birds nesting in the Midwest and wintering in the South. But today it involves a staff of about a dozen people and the cooperation of volunteer property owners, who host the birds and the aircraft as they step-stone their way between the distant refuges. In the spring, and in future years, the cranes will return on their own to Wisconsin without human assistance.
The breeding, training, migration, and monitoring of these pioneering birds is coordinated by the Whooping Crane Eastern Partnership, a group of NGOs and state and federal agencies that includes the USFWS. By February 2008, about 75 birds were in the Necedah flock. Seventeen of these were captive-hatched birds guided by ultralight and seven were “direct-releases,” late spring- or summer-hatched birds introduced to an established flock in hopes that young birds will go with the flow and learn from their comrades how to reach Florida. In 2006, a whooping crane pair nested at Necedah. One chick survived, migrated to Florida, and returned the next spring to Necedah with its parents.
For the time being, though, only the wild Canadian flock is self-sustaining. “The verdict’s still out on the Wisconsin population,” said Archibald. “For inexplicable reasons, they are abandoning nests in Wisconsin when weather warms in spring. We are by no means out of the woods.”
The whooping crane may be numerically the rarest of cranes, but it’s not considered the most endangered. The Siberian crane wins this dubious honor. On the World Conservation Union’s 2007 IUCN Red List of Threatened Species, the species is listed as critically endangered.
Conservationists are holding their breath to see if China’s colossal new Three Gorges Dam creates drastic hydrological changes that could forever alter the birds’ stopover and concentrated wintering sites along the Yangtze River. Stretching one and a half miles across the Yangtze, the dam is the world’s largest concrete structure. Its great restraining power may alter the hydrology of many nearby areas, including one of China’s largest freshwater lakes, Poyang Hu. Poyang Hu is one of the world’s most important crane wintering areas. There, virtually all 3,000 to 4,000 Siberian cranes winter, along with small numbers of hooded cranes (G. monacha), and up to 3,000 white-naped cranes (G. vipio), perhaps half of the world population.
While hooded and white-naped cranes winter in other areas as well, the Siberian crane now has all its eggs in one basket. This was not always the case. Western and central populations once wintered in northern Iran and northern India, but these petered out over the years, due in good part to hunting along their migration paths. Birds wintering in India, for example, had to wing their way over gun-rich Afghanistan and Pakistan. The last sighting of an India-wintering bird was during the winter of 2002. In northern Iran, a lone Siberian crane was spotted in 2007. Conservationists hope to revive these populations, and a few reintroduction attempts have begun, but success, as with the whooping cranes, will require an expensive, uphill battle. Reintroduced birds will need to learn—and teach their young—to migrate between Russia and Iran or India. But any effort seems destined to fail if hunting cannot be controlled within all range countries.
Not all cranes are in dire straits. Some remain abundant, particularly those that feed and stop over in farm areas. The sandhill crane is by far the most numerous. Sandhills nest in the United States and Canada, and also in northeastern Siberia and Cuba, where a small nonmigratory population persists. In the midwestern United States, the sandhill population is growing and expanding: In Wisconsin, for example, the population recovered from a low of about 100 birds in the 1930s to more than 12,000 today. Since the 1990s, a few pairs have even nested in Pennsylvania and Maine. In New England and the Mid-Atlantic states, sightings of wandering birds are on the rise.
Sandhills and other cranes often eat waste grain and pests such as beetle larvae in farm fields, but they also snap up newly planted corn kernels and other crops in spring. In some cases, large sandhill flocks cause considerable damage. Seeking peace between migratory birds and workers of the soil, conservationists worked with chemists to devise non-lethal repellants that keep cranes from ruffling farmers’ feathers. In 2007, a liquid formulation of Avitec began to be applied in corn fields in four states where the Environmental Protection Agency (EPA) approved it for trial use—Michigan, Minnesota, Texas, and Wisconsin. Avitec contains a naturally occurring plant substance, anthraquinone, which cranes find distasteful. So far, when applied to corn kernels before planting, it’s been effective in keeping cranes away from planted kernels while they continue to feed on pests and waste corn in the fields. EPA approval of Avitec for more widespread use may come by 2009.
With wetlands greatly reduced in many parts of the world, many cranes now frequent landscape mosaics that blend small wetlands and agricultural fields. Farmers’ acceptance of cranes is essential to the birds’ survival. Each spring, for example, grain fields along the Platte River in Nebraska host about 80 percent of all sandhills—up to 500,000 birds—which pass over and stop along a 75-mile stretch of the river. Each March during the peak of sanhill migration, the popular Wings over the Platte Festival marks this passage, drawing thousands of camera-toting tourists whose attention and money further help local communities appreciate their wandering winged neighbors. Tours of crane-covered fields fill fast. By April, most of the cranes have moved farther north, toward their nesting grounds.
|The Stanley crane is the national bird of South Africa. (Jessie Cohen, NZP)|
For decades, George Archibald has been involved in global efforts to save cranes. Does he believe that modern human demands can somehow harmonize with the primordial needs of cranes? Archibald says it’s all up to humanity: “People have to care about cranes. If they don’t shoot, trap, or poison them and the birds have some wetland habitat, they can live very near to people,” he says. “If people don’t care about them, they’re gone.”
As cultural and natural treasures, cranes galvanize governments’ resolve to save these emblematic birds. Since 1993, for example, all 11 countries where Siberian cranes nest, winter, or pass through have coordinated monitoring and conservation efforts aimed at saving the species under a signed memorandum of understanding. Recent efforts focused on establishing a protected network of important crane migration and wintering sites. Conservationists in Mongolia, Russia, and China study, monitor, and protect white-naped crane breeding areas in the Daurian Steppes region shared by these three countries.
Since 1994, ICF, the New York-based Trickle Up Program, and local agencies in China have worked together on a novel project that helps local communities improve their prospects while enhancing protection of the Cao Hai National Nature Reserve, an important wintering area for black-necked (G. nigricollis) and common cranes, as well as bar-headed geese (Anser indicus) and other waterfowl. By setting up trust funds, giving small loans to family businesses, and starting education programs, the project has helped communities take an active role in protecting the reserve while raising their incomes through sustainable businesses that don’t adversely affect local wildlife.
And then there is the hopeful saga of the whooping crane. If not for cooperation between U.S. and Canadian government agencies and private organizations, this bird would have joined the growing list of extinct birds. Instead, whooping crane numbers are increasing under the watchful eye of conservationists including USFWS whooping crane coordinator Tom Stehn, who, 23 years after giving me a ride in his pickup, is still at it.
“I started doing census flights in 1982,” wrote Stehn in January in his regularly updated whooping crane count at www.birdRockport.com. “This initial flight in 2008 marks my twenty-seventh different calendar year trying to maintain my equilibrium as we do aerial maneuvers looking for cranes.” Stehn estimates that a record 266 whooping cranes wintered in Texas this year, gorging on blue crabs and wolfberry fruits. That’s a far cry from the 94 birds he estimated while we drove across Aransas in 1985. And it’s great news not only for birds but also their admirers, including those like Stehn who dedicate their lives to keeping the charismatic cranes flying strong.
Contributing editor Howard Youth will soon write from South America, one of only two continents to lack wild cranes.