Note from Colleen: Don't worry about pronouncing the names completely right. Names like these are from another language (Swahili), so I don't know how to pronounce them completely right either! Let me know what you think next class so we can look at more sources for articles together.


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Flocks of pink-plumed African lesser flamingos descend on the banks of Tanzania’s Lake Natron every year, maintaining a delicate balance of life and death that experts say may be endangered by human plans to develop the salt lake’s natural resources.

The lesser flamingos, so named for being the smallest of six species, feast on algae from neighboring lakes in Kenya and Tanzania, then fly many miles to Natron to mate. The birds are choosy breeders; Natron is the sole mating site for the estimated 1.5 million lesser flamingos in East Africa.

As Natron’s soda ash islands incubate new flamingo life, its banks are littered with the corpses of small birds and animals that accidentally fall into its alkaline-rich waters and eventually wash up, dead and crusted over with salt.

The brilliantly feathered flamingos themselves are given to occasional mass die offs, sometimes felled by disease that sweeps swiftly through its crowded flocks, or killed by seasonal toxins in the algae mixes that they eat.

To make the lives of these birds just a little bit more precarious, they must also contend with the plans human beings have for Lake Natron. On the horizon are plans for a soda ash plant, and investigations are under way for a geothermal facility.

If either of these projects reaches fruition, the birds’ one breeding ground will be endangered: “In 50 years the flamingos will go extinct in east Africa,” said the University of Leicester's David Harper, who studies the birds.

Life and death on the banks of Lake Natron
Flamingo flocks arrive at Natron annually, even though each bird will mate only once every four or five years. A courting pair, plump from gulping down red algae and blushing from the pigment that the microbes leach into their skin, will produce a single oblong egg, laid in a miniature salt island made of the soda ash that precipitates out of the lake water as the water evaporates.

But large numbers of flamingos also have a tendency to die all at once, for reasons that remain unclear to researchers.

In fact, when Harper first visited Lake Bogoria in Kenya in 1989, he walked into one of the bigger die-offs in the East African population’s history. He counted up to 1,000 fallen birds in a single day, and estimated that about 200,000 birds were lost that season.

“There’s no certainty about why flamingos die in large numbers,” Harper said, but theories have suggested an infectious bout of pneumonia, he said.

The flamingos’ numbers are replenished every year, in spite of the birds’ fussy mating habits.

“In the next three years, we counted more than 200,000 young birds, so we know the mortality was replaced,” Harper said. An annual flamingo census indicates that the size of the population has stayed constant for the past two decades.
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