A high-altitude specialist
The Salar de Atacama, a vast salt flat in northern Chile, is a habitat for the Andean flamingo, Phoenicoparrus andinus. This species is the rarest of the world's six flamingo types. It lives in the high-altitude wetlands of the Andes, typically between 2,300 and 4,500 meters, across Peru, Bolivia, Chile, and Argentina. Of the three flamingo species found in the Andes—Andean, Chilean, and James's—the Andean flamingo is the largest, standing up to 1.4 meters tall.
A distinguishing feature is its legs and feet, which are yellow—unique among all flamingos. Its bill is also distinct, pale yellow near the base and black for most of its length. This bill is a specialized tool. The Andean flamingo has a deep-keeled mandible with fine filtering filaments, perfectly adapted for its diet. It feeds primarily on diatoms, a type of microscopic algae, which it filters from the soft sediment of alkaline and saline lakes. The carotenoid pigments in these algae are responsible for the flamingo's pale pink plumage; chicks are born gray or white and take up to three years to acquire their adult coloration.
The species is highly social, forming large colonies that can include tens of thousands of birds, often mixing with the other local flamingo species. They build cone-shaped nests from mud, typically laying a single egg which both parents incubate for about 28 days.
A single, vulnerable population
The total population of the Andean flamingo is estimated at approximately 39,000 individuals, classifying it as a vulnerable species. Threats include habitat degradation from mining activities—particularly for lithium, as the region is a major source—unregulated tourism, and water contamination. Historically, egg collecting was also a major pressure. These factors have contributed to a decline in successful breeding colonies, especially in Chile.
Genetic studies on flamingo populations, including the closely related Chilean flamingo, show a general lack of significant genetic structure across their wide ranges. This suggests that the birds form a single, large metapopulation. Andean flamingos are highly migratory and can travel up to 1,100 kilometers in a day, moving between breeding and non-breeding sites across the borders of Argentina, Bolivia, Chile, and Peru. This nomadic behavior and the resulting gene flow mean that the flamingos in the Salar de Atacama are not an isolated group, but part of a larger, interconnected population.
This genetic connectivity affects conservation. An impact on the habitat in one country, such as water diversion from a mining operation in Chile, can directly affect the breeding and survival of flamingos that winter in Argentina or Bolivia. Protecting this species requires coordinated, international efforts among the four nations that host these birds. A Memorandum of Understanding for the conservation of High Andean Flamingos is in effect under the Convention on Migratory Species to facilitate this cross-border cooperation.