Farewell to Flamingos?
Three species of these hot pink birds are dwindling away in a key breeding area way up in the Andes
THE HIGH PLATEAU or altiplano of South America's central Andes is a hard place to eke out a living—for humans, creatures or plants. Covering about 120,000 square miles, this cold, treeless desert, swept by icy winds, seared by intense solar radiation and pocked by desolate, salty lakes called salars, extends in an arc through Argentina, Chile, Bolivia and Peru and lies more than 11,500 feet above sea level. The desert's sparse animal life includes foxes, pumas, oddball rodents called vizcachas that leap like kangaroos, ostrichlike rheas, giant coots, majestic Andean condors and vicuñas, from the camel family.
But to wildlife conservationists, the altiplano is the astonishing "mountain flamingo crescent," where three of the world's six flamingo species congregate. Two of them, the James and Andean flamingos, can be found year-round among the world's highest volcanoes, crowding into open water near hot springs in winter, when nighttime temperatures drop to minus 20 degrees F and the salars otherwise freeze solid. Both species are rare and threatened by a medley of issues ranging from mining to unregulated tourism. In the breeding season, they are joined by populations of the more abundant and wider-ranging Chilean flamingo.
Photo: © PETE OXFORD AND RENEÉ BISH
IN THE PINK: Snowcapped Andes overlook James flamingos feeding at Laguna Colorada, a nesting site for this rarest of flamingo species.
The other three species are the Caribbean flamingo, seen in the Bahamas, the Galápagos Islands and along the coasts of Cuba, Venezuela and Mexico; the greater flamingo, found from Africa and the Mediterranean to Kazakhstan and India and is the largest of its kind; and the smallest and most plentiful species, the lesser flamingo, numbering in the millions in Africa's Rift Valley.
With their long legs and necks and distinctive pink plumage, flamingos are the epitome of avian elegance. And many observers consider the Andean and James flamingos to be the most beautiful of the six. The head, neck and breast of the Andean flamingo sport a wine-red hue, and the species is the only flamingo with yellow legs and feet. The James flamingo's back is draped with long scarlet plumes in the breeding season, and its breast is streaked with carmine. Except for its red knees and feet, the livery of the Chilean flamingo, dazzlingly pink though it is, seems almost unremarkable by comparison.
Of course, every design in nature has its purpose. In the case of flamingos, those long legs and necks enable them to wade to greater depths than any other water birds while lowering their heads into the water to scour the bottom mud for food. In addition, their front toes are webbed for mud-walking—or for paddling like geese in deeper waters.
High atop the Andes may seem an unlikely place for flamingos to gather, but in fact the altiplano lakes are typical of flamingo habitats around the world—shallow, alkaline or saline lakes and lagoons with caustic waters that are astonishingly rich in diatoms, algae and aquatic invertebrates. How three similar species with similar needs manage to feed side by side in this limited environment without competing for resources is one of the bird world's gee-whiz stories.
The secret lies in the extraordinary flamingo bill, with its keel shape and rows of horny, baleenlike strainers (or lamellae) on the mandibles. William Conway, senior scientist with the Wildlife Conservation Society at New York's Bronx Zoo, once measured the "teeth" in the combs of the three and counted 13 to the inch in the Chilean flamingo, 23 to the inch in the Andean and 54 to the inch in the James. The birds feed with their bills held topside-down, pointing backward and slightly open with the lamellae flattened, using their plungerlike tongues to suck in water, mud and food items up to a certain size. Then the tongue pumps the water and smaller food particles out through the raised lamellae.
Thus each species has its own, separate food supply. The James and Andean flamingos feed entirely on tiny diatoms that are about 0.6 and 0.8 millimeters in length, respectively, while the Chilean flamingo has more catholic tastes, straining out brine shrimp, copepods, fly larvae and other small invertebrates.
The Chilean flamingo also has unusual feeding tactics apparently related to prey mobility. While the James and Andean species move at the rather stately pace of 10 to 15 and 20 to 30 steps per minute respectively, the Chilean is a veritable speed demon, striding around at 40 to 60 steps a minute to stir up invertebrates from the lake bottom. This frenetic activity in turn sometimes attracts Wilson's phalaropes—shorebirds that nest on the Great Plains of North America and winter in immense numbers on these high Andean lakes. Two or three phalaropes will attach themselves to a feeding Chilean flamingo, whirling around and through its legs, snatching food items with a minimum of their own effort.
The range of the Chilean flamingo extends from central Peru to Tierra del Fuego and eastward to southern Brazil, Uruguay and the Argentine pampas, and the birds are seen as often on coastal estuaries as on the high salt lakes. Recent estimates put the species population at 200,000.
But counting flamingos is no easy task, especially in a region as remote as the Andean altiplano, where the birds move from lake to lake as water conditions change. Indeed, for decades the James flamingo was believed to be extinct, since no ornithologist had seen one since 1924. Then, in 1957, a Chilean expedition found the bird breeding at Laguna Colorada, 14,035 feet up in the Bolivian mountains.
In 1972, Philip Kahl, a noted wading bird biologist, attempted a one-man survey of the mountain flamingos, funded by the National Geographic Society. He says the endeavor was "the most frustrating project I ever worked on. The area is vast, the distance between lakes is great and planes are expensive." He remembers "blowing an entire month's budget" on a long flight from La Paz, Bolivia, to Laguna Colorada and finding no flamingos at all. "The lake was empty."
Photo: © PETE OXFORD AND RENEÉ BISH
EGGS ON ICE: Andean flamingos nest in January amid patches of snow at Laguna Colorada, almost 14,000 feet above sea level. Flamingos seem typically tropical, but two of the three species of the Andes—the Andean and James flamingos—live year-round among the highest volcanoes in he world, where winter nights can fall to minus 20 degrees F. The birds ward off the cold by crowding into open water near hot springs. They feed on a mix of diatoms, algae and invertebrates such as brine shrimp.
However, Kahl's "wild guess" of 50,000 James and 150,000 Andean flamingos provided the best numbers available until January 1997, when the Wildlife Conservation Society, which has made protection of South American flamingos a priority, spearheaded the first comprehensive and simultaneous census of the two rare species. Teams of volunteers from Peru, Bolivia, Chile and Argentina—four nations whose diplomatic relationships are sometimes strained—visited some 100 saline lakes in the same week, counting flamingo groups numbering from a few hundred to a few thousand birds. They tallied 47,600 James flamingos, which compared favorably with Kahl's earlier estimate, but only 34,000 Andean flamingos, confirming fears of a precipitous decline. A follow-up survey of 133 lakes a year later turned up 64,000 James and just 27,800 Andean flamingos.
Those figures, the Conservation Society's Conway warns, are misleading, since they suggest that the species are not rare or threatened. "The number of successful breeding colonies is almost as important as the number of individuals," he explains, adding that only three nesting colonies were found in Bolivia in the 1997 survey, with five more in Chile and none in the mountains of Argentina and Peru.
Flamingos, which lay a single egg atop a cone-shaped pile of mud and raise offspring on secreted milk rich in protein and fat, are long-lived birds that have survived for 50 years in zoos, Conway says. "They can appear to be doing fine when, in reality, they are raising no young because their breeding sites have become untenable. Meanwhile, the population grows older. There could be a lot of near-senile birds out there."
Moreover, year-to-year nesting success is unpredictable. James flamingos at Laguna Colorada, the species' most important breeding site, raised 10,500 chicks in 1997 but only 1,260 the next year. Surveys of six Andean flamingo colonies in Chile found just 200 chicks in 1997 and merely seven in 1998. Drought conditions and excessive evaporation can dry up lagoons and wipe out breeding seasons or leave nests vulnerable to predatory foxes.
Biologists point out that a few breeding successes every five to ten years are sufficient to maintain stable flamingo populations, but they worry about a host of conservation issues, not the least of which is the minimal protection accorded the birds and their habitats, even in protected reserves.
For example, Laguna Colorada, also know as Red Lake (for the color of its algae-rich waters) lies within the Eduardo Avaroa National Reservation of Andean Wildlife, created by Bolivia in 1973. But the integrity of the lake, which covers an area of 23 square miles with an average depth of only 14 inches, is threatened by borax mining and geothermal development. A resurgence of flamingo egg harvesting by local Indians, who supply markets in nearby mining towns, also jeopardizes the birds. Still another concern is disturbance of nesting birds by tourists, numbering some 30,000 a year, who visit the preserve during the summer breeding season.
In Chile, mining ranks as a national priority, and at Salar de Punta Negra, a critical nesting site for Andean flamingos in the Atacama Desert, the pumping of underground water for a huge copper mine threatens to dry up the wetlands. The mining company, which began operations in 1988, has experimented with various remedial tactics, such as rescuing abandoned flamingo eggs and raising the chicks for release in the wild as well as trying to recreate wetlands through surface recharge. Conservationists wonder if such expensive investments in window-dressing could be better directed to protection in the wild.
In southern Peru, Laguna de Salinas hosts several colonies of Andean, James and Chilean flamingos. But even though the lake has been part of a nature reserve for more than 20 years, the level of protection leaves much to be desired. A foreign company uses heavy machinery to drain the lake and mine borates, fragmenting the habitat with roads. Local people obtain salt by creating drying plots, reducing the lake's coverage; collect eggs from inflated inner tubes; and use flamingos for target practice during the hunting season. Refuse from nearby hamlets washes into the lake during the rainy season.
One of the most important nesting areas for the Chilean flamingo, meanwhile, is Mar Chiquita, which lies close to sea level near the Argentine city of Cordoba. Ranking among the world's largest salt lakes, Mar Chiquita covers 2,700 square miles in high water years, during which the flamingo breeding population has reached 100,000 birds and produced 40,000 young. Andean and James flamingos also visit the lake during winter months. Biologists say that nesting success is directly related to the availability of islands with extensive mudflats and a supply of fresh water and nutrients from incoming rivers. But Mar Chiquita is seriously threatened by government projects that would divert stream flow for irrigation and urban water demands.
Still, Felicity Arengo, assistant director for Latin America programs at the Wildlife Conservation Society, is cautiously optimistic about the flamingos' future. She reports that concerned scientists, natural resource managers and conservationists from Argentina, Bolivia, Chile and Peru have formed the Grupo de Conservacion de Flamencos Alto Andinos to work on joint research projects and develop a conservation strategy. "The goal," she says, "is to get as much biological information as we can to make sound conservation decisions. In some cases it will be designing or declaring protected areas. Or it could mean working with other interests, like mining, to minimize their environmental impacts."
Fieldwork on the high Andes lakes is grueling at best. It means struggling through sucking, knee-deep mud in thin air, biting winds and relentless sun. "I took a colleague from the Bronx Zoo to help on a research project at Salar Atacama in Chile," says Arengo, "and he said it was the most godforsaken place he had ever seen." But she hastily adds, "I think it's beautiful." Kahl recalls that the famous birdman Roger Tory Peterson nearly succumbed while trying to photograph James flamingos at Laguna Colorada shortly after their rediscovery.
Given the difficult field conditions, it is no surprise that much remains to be learned about the biology of the mountain flamingos. But flamingo field researchers are making progress. Arengo is excited about the information being gathered about the travels of Andean flamingos from five adults she and colleagues from the University in Salta, Argentina, outfitted with satellite transmitters. "We thought the birds would hang out at a particular lake for weeks at a time, but we've discovered that they're moving about more frequently and traveling long distances. One bird covered 620 miles in a four-day period, and individuals tagged in Chile and Argentina ended up at the same lake in Bolivia. These data are incredible!"
She might well have said the same of the determination of so many dedicated biologists to collect such data, which is key to ensuring that the altiplano flamingos survive the myriad threats they face.
Field Editor Les Line recently wrote about climate change and grosbeaks for National Wildlife. He has observed Chilean flamingos in Argentina.