Human encroachment dispersing Kenya's flamingoes.
Kenya's world-famous flamingo is being driven from its natural sanctuary in Lake Nakuru by pollution, its millions-strong flocks diminishing sharply over the past three years as the birds migrate to other parts of the Rift Valley.
The flamingo has for years been a major tourist attraction in East Africa. It feeds on a blue/green algae, spirulina platensis, which blossoms in saline water.
But part of its natural habitat -- Lake Nakuru -- is dying off because of human activity. Recently, the birds have migrated to other lakes in the Great Rift Valley, notably Lake Bogoria, north of Nakuru town.
Lake Nakuru National Park, once famous for its millions of flamingoes, is losing its longtime glory. The bird sanctuary now looks deserted except for a few pelicans.
Ornithologists blame changes to their habitat.
"Flamingoes are suffering from environmental stress. Salinity levels in Lake Nakuru have been fluctuating from time to time, hence affecting their way of survival," said Ramesh Thampy of the World Wildlife Fund (WWF).
Thampy argues that the birds have been leaving their hideouts due to lack of food coupled with unfriendly surroundings. The lake, lying a few miles from the town, has been polluted by industrial refuse and other wastes, rendering it unfit for marine life.
"In the past years, there's been growing cultivation within the neighborhood. This has affected the catchment areas of the lake," he said.
Thampy theorizes that unexplained flamingo die-offs may be the result of the birds' accumulating potentially toxic substances in their bodies.
More than 60,000 flamingoes died in Kenya between 1993 and 1995 -- dealing a major blow to the country's tourism industry.
Dozens of flamingoes are, once again, dying in Lake Bogoria in bizarre incidents. "These are unusual die-offs," said William Kimosop, a senior warden at Lake Bogoria Game Reserve since 1989.
Lake Bogoria, famed for its hot springs, stands at the center of the Rift Valley. It has now become home to more than 1 million flamingoes. The 6-meter-deep lake does not dry up, unlike other lakes in the region.
Experts say flamingoes are a unique species. Although sporadic research has been done, they say, little is known about the birds. In Kenya, for instance, the flamingo has been known only for the last 25 years.
The WWF, which has been monitoring the birds' behavior for the last two years, says the high death rate in Lake Bogoria may be due to stress. "There is the possibility of over-flocking in the lake, which may cause fatal stress," says Jackson Raini, an assistant field officer with the WWF.
However, Kimosop, who has been looking after the birds for more than ten years, said, "The birds may be dying from heavy metals accumulated in their bodies over many years." He adds the birds have been migrating from one lake to another in search of food.
"Lake Nakuru is not fit for these birds, considering its rate of pollution," he said. "The industrial wastes from the town end up into the lake."
But John Githaiga, a lecturer at the University of Nairobi's Zoology Department who has researched the birds' behavior, said, "The changes are very natural." He said he believes the birds are migrating for breeding purposes to Lake Natron, in northern Tanzania. "They also leave due to changes in water quality," he said.
He says that since 1996, there has been more rapid deforestation in the vicinity of Lake Nakuru, which has affected the water inflow into the lake.
There are about 5 million flamingoes in Africa, of which at least 3.5 million are in East Africa. Bird experts estimate that, in captivity, flamingoes can live up to 50 years.