Lesser flamingo

Lesser flamingos eat tiny green and blue food called algae.

They hold their beak upside down in the water. Their beak works like a sieve and catches the food.

Lesser flamingos eat almost nothing but tiny algae, so small you would need a microscope to see them, especially a blue-green kind called spirulina. These algae grow in salty, alkaline lakes.

To feed, a flamingo holds its bill upside down in the water, sucks water in and pumps it out through the sides. Inside the bill are rows of tiny plates called lamellae, up to about 10,000 of them, that act like filters and trap the algae. The pink color of flamingos comes from natural pigments in the food they eat.

The diet consists almost entirely of microscopic blue-green algae (cyanobacteria such as Spirulina, Oscillatoria and Lyngbya) and bottom-living diatoms found only in alkaline lakes, salt pans and saline lagoons; small invertebrates such as rotifers are taken to a lesser extent (IUCN). The bill holds up to about 10,000 microscopic lamellae.

Lesser flamingos feed mostly at night and in the early morning, when the water surface is calm, often swimming and filtering near the surface. When needed, they form large, dense feeding flocks that calm the water at the center. The San Diego Zoo notes that the smaller flamingos have deeper bills with stiff lamellae for filtering very fine particles, and that carotenoid pigments in the food give flamingos their color.

Lesser flamingos love company.

They feed, fly and nest together in giant flocks. Sometimes there are more than a million in one place!

Lesser flamingos are very social. They do almost everything in groups, and in East Africa more than a million may gather together.

Flamingo flocks perform group displays, such as head-flagging, when they stretch their necks up and turn their heads from side to side, and marching, when a tightly packed group walks together and suddenly changes direction. These displays help many birds get ready to nest at the same time.

Lesser flamingos are highly gregarious and nomadic, moving between lakes as water and food conditions change. Flamingo flocks perform ritualized group displays such as head-flagging, wing salutes and marching, which the San Diego Zoo explains help synchronize breeding across the flock.

The IUCN notes that large, dense feeding flocks can calm the water at their center, improving feeding conditions, and that some researchers have suggested breeding failures, possibly lasting 10 or more years, may not affect overall population dynamics.

Lesser flamingos need their salty lakes to stay safe.

There are only a few places where they make their nests. People are working to protect those lakes.

The lesser flamingo is listed as Near Threatened because its numbers seem to be falling. Even though there are millions of them, they nest in only a few places. The most important is Lake Natron in Tanzania.

Plans to mine soda ash and build power projects at Lake Natron could harm the nesting colony. When the IUCN last checked, in 2018, these plans were on hold. Other problems include pollution, changes to the land around lakes and flamingos flying into power lines. People help by protecting breeding lakes and even building nesting islands.

The IUCN's 2018 assessment lists the species as Near Threatened (A2c+3c+4c) with a decreasing trend, citing habitat degradation and disturbance. Only three main breeding sites exist in Africa and one in India. Proposed soda-ash mining and hydroelectric schemes at Lake Natron, the most important colony, were on hold but had not been withdrawn (the IUCN cites a 2008 report and still called them on hold in 2018); the IUCN says such development would be disastrous and could justify a higher threat category.

Other threats include land reclamation, water pollution and collisions with power lines. Conservation actions include CITES and CMS Appendix II listings, an international action plan (2008), a flamingo sanctuary at Botswana's Makgadikgadi salt pans (2009) and successful breeding on an artificial island at Kamfers Dam, South Africa.