LAKE NAKURU, Kenya The emerald-green waters of Kenya's Lake Nakuru are once again fringed with pink as over a million flamingos take advantage of ideal weather caused by El Nino's rains and flock to the ancient soda basin. The flamingos, largely absent from Lake Nakuru in the Rift Valley for the last decade, have returned in force and an official count in January recorded more than 1.5 million birds.

They are back and it is very nice to have them, said Daniel Kilonzo, senior warden with Kenya Wildlife Services based at Nakuru National Park which surrounds the lake. I hope they will stay this time...the visitors come mainly to see them and are unhappy when they are not here. Lake Nakuru, a shallow salt lake which formed millions of years ago when Africa's continental shelf split to form the Rift Valley, has long attracted flamingos which feed on the specialized algae which thrives in its warm, brackish waters.

But falling water levels in the mid 1980s until late last year affected its salinity and the flamingos deserted Nakuru for richer feeding in more remote waters to the north. Shores of Nakuru a Shocking Pink Today they are back, and the shores of Nakuru just three hours by car from the capital Nairobi are a shocking pink once again. The cacophony of more than a million chattering flamingos one of the most sociable birds in the animal kingdom fills the air and the heady scent of their guano burns the nostrils with an acidity that lingers for hours.

The heavy rains have also proved a boon for dozens of other species of birds in this wildlife-rich east African country. More than 100 species were spotted on a recent visit to Nakuru including the foppish long-crested eagle, the shy augur buzzard, stilt-legged secretary birds and dozens of dazzling, iridescent starlings. The mammals have also benefited. Sleek, well-fed lions keep watch as they laze in the low-slung branches of acacia trees, their playful cubs gambolling in the long grass below.

At dusk, as the sun sets, the lucky visitor might see a dappled leopard slinking shyly through the forest that surrounds the lake. But it is the flamingos that draw most visitors to Nakuru. There are five types of flamingo in the world and east Africa is home to two of the most typical of the species the lesser and the greater.

Perfectly Adapted to Their Environment The lesser, a deeper shade of pink, is a herbivore that feeds on micro-vegetation in the salt lakes. This algae which gives the lake its unique color thrives on the guano produced by the flamingos in one of the most efficient food cycles in the animal kingdom. The greater flamingo a more elegant, larger and paler version lives in smaller numbers alongside its lesser cousin and feeds on invertebrates from the mud on the lake bottom.

Both species are perfectly adapted to their environment. Their long, thin legs dissipate the heat from the lake waters which in shallow pools sometimes reach temperatures hot enough to boil an egg and their elongated necks ensure that blood is further cooled before it reaches the brain. In the heat of the day they balance elegantly on one leg which further reduces body temperature.

Studies show the birds are either right or left-legged, a trait that is inherited. If they get too cold, the birds reverse the process by bathing with splashy abandon, their huge wings fluttering in unison like a chorus-line of feathered dancers at the Moulin Rouge. Because they live on microscopic organisms, the flamingos spend most of their waking hours feeding which they do by dipping their heads upside-down in the water and slurping the algae-rich soup through fine hair-like filters in their L-shaped bills.

Their muscular tongues considered a delicacy by the ancient Greeks act as a piston, squirting water out through the sides of their bills. As adults they have few predators, although hyenas frequently take advantage of moon less nights to run amok in the flocks and emerge, almost comically, with their mouths stuffed with pink feathers. But as chicks they are vulnerable to the harsh elements and adult birds create conical cooling mud nests on the shores of their breeding grounds, leaving the area looking like a beach decorated with a million small sand-castles.

El Nino Rains Good News for Nakuru The healthy El Nino rains mean Nakuru is not in danger of drying-up again for a few years at least, leaving experts to predict that the flamingo population will once again top the two-million mark of the mid 1960s. With populations of the size of the current Nakuru flock, the birds are so crowded that huge numbers have to coordinate their activities so they can move without jostling their neighbors.

This produces the fabulous synchronized feeding, courting, landing and take-off displays for which the flamingos have become a photographer's dream. I came all the way to Africa just to see this nothing else, said Yomuri Osakato, a Japanese tourist who had spent dozens of rolls of film on capturing the spectacle. They are the most beautiful birds in the world, he added, and he doffed his cap bedecked with dozens of cast-off pink feathers, to the multitude.

(Reuters)