Travel to Eduardo Avaroa Andean Fauna National Reserve

In Bolivia’s extreme southwestern corner, where the country meets Chile and Argentina, lies a protected wilderness so otherworldly that visitors often describe it as another planet. The Eduardo Avaroa Andean Fauna National Reserve, established in 1973 and named after a hero of Bolivia’s War of the Pacific, covers 714,745 hectares of high-altitude desert, volcanic peaks, and mineral-stained lagoons at elevations between 4,200 and 5,400 meters. This is the altiplano at its most dramatic, a cold, wind-swept expanse where nights regularly fall below minus 10 degrees Celsius, with extremes near minus 20, days are bright but cool, and rainfall barely reaches 76 millimeters a year.

The reserve’s centerpiece is Laguna Colorada, a shallow salt lake that glows crimson from pigmented algae and rich mineral sediments. Spanning about 60 square kilometers but rarely more than 80 centimeters deep, its blood-red waters are dotted with white islands of borax that create an almost impossible contrast. In 1990 the lake was designated a Ramsar Wetland of International Importance, recognition of its role as one of the most critical flamingo habitats on Earth. Here three of the world’s six flamingo species gather in colonies numbering tens of thousands, their pink forms mirrored in waters that seem borrowed from a dream.

The James’s flamingo, also called the puna flamingo, holds a remarkable place in ornithological history. First described in 1886 and named for the British naturalist Harry Berkeley James, this small, pale-pink bird with bright carmine streaks seemingly vanished from scientific observation in the early twentieth century. For decades researchers presumed the species extinct, another casualty of the remote and unforgiving altiplano. Then, in 1956 and 1957, an expedition led by A. W. Johnson reached Laguna Colorada and made an astonishing discovery: thousands of James’s flamingos nesting among their Chilean and Andean cousins in the red waters of this volcanic basin.

Today, nearly one-third of the entire world population of James’s flamingos, estimated at more than 100,000 birds, breeds at Laguna Colorada alone. They share the reserve with the Andean flamingo, the rarest of the world’s flamingos with only around 38,000 to 39,000 left, and the more common Chilean flamingo. All three filter-feed on the diatoms and algae that thrive in these saline waters, their specialized bills straining microscopic food from the mineral-rich lakes. The birds’ pink color comes directly from that diet, the same pigments in the algae that redden the lake also tinting their feathers. Watching thousands take flight against the snow-capped volcanoes is one of South America’s great wildlife spectacles.

South of Laguna Colorada the landscape turns volcanic. Sol de Mañana, meaning morning sun, is a geothermal field of around 10 square kilometers at 4,900 meters, one of the highest on Earth. Fumaroles hiss sulfurous steam, mud pools bubble and churn, and columns of vapor rise against the thin mountain air. The heat comes from far below, where the underground reservoir reaches some 250 degrees Celsius, part of the vast Altiplano-Puna Magma Body that underlies this corner of the Andes. Visitors walk carefully between the vents, as the thin crust has no barriers and the ground is genuinely dangerous in places.

The reserve’s southwestern edge delivers its final flourish: Laguna Verde, an emerald lake at around 4,310 meters whose intense color comes from suspended arsenic, copper, and other minerals. Unlike its red sister to the north, this lake is too toxic for flamingos, but its turquoise-to-emerald hues shift with the wind beneath the near-perfect cone of Licancabur. Rising to 5,916 meters on the Bolivia and Chile border, this stratovolcano holds one of the highest crater lakes on Earth at its summit, along with Inca ruins on its rim. The mountain was sacred to the Inca, and watching its reflection shimmer in the green water, it is easy to see why.