High-altitude incubation
The Salar de Tara, a salt flat within the Central Andean Dry Puna ecoregion, is a high-altitude wetland in the Andes mountains. At an average elevation of 4,000 meters, this environment presents extreme challenges for life. The air has low oxygen, solar radiation is intense, and temperatures fluctuate dramatically. It is in this harsh setting that three of the world's six flamingo species breed: the Chilean (Phoenicopterus chilensis), the Andean (Phoenicoparrus andinus), and the James's flamingo (Phoenicoparrus jamesi).
James's flamingo, also known as the Puna flamingo, is the smallest and rarest of the three. It often nests at elevations up to 4,870 meters (nearly 16,000 feet). The breeding season coincides with the austral spring and summer, beginning around November. Pairs build cone-shaped nests from mud, stones, and plant debris, with a shallow depression on top for their single egg. Incubation takes approximately 27 to 31 days, during which both parents share responsibility. The most significant challenge is the cold. Nighttime temperatures can fall below -20°C, a condition that would freeze and kill the embryos of most other birds. The specific biological mechanism that allows these flamingo eggs to remain viable is not yet fully understood by scientists.
Life on the salt flat
The flamingos' survival here depends on a highly specialized diet and unique physical adaptations. The shallow, saline lakes of the Altiplano are inhospitable to most animals but support blooms of microscopic diatoms and algae. James's flamingos feed by filtering these organisms from the water using a specialized bill. The carotenoid pigments in the algae are responsible for the birds' pink plumage.
To cope with the low oxygen at high altitudes, these flamingos have blood with a high concentration of hemoglobin. To manage the high salt content of their food and water, they possess salt glands in their nostrils that excrete excess salt. When the wetlands freeze over in winter, making food inaccessible, most of the flamingos migrate to lower altitudes. Some birds may remain year-round where volcanic hot springs keep small areas of the lakes from freezing. The population of James's flamingo is estimated at over 100,000 individuals, but the species is considered Near Threatened by the IUCN due to its restricted range and threats from mining operations and climate change, which affect water levels and food supply.