The Planet's Northernmost Flamingos
In the vast, treeless steppe of central Kazakhstan, 130 km southwest of the capital city Astana, lies the Korgalzhyn State Nature Reserve. This protected area, a UNESCO World Heritage site covering 543,171 hectares, is a group of freshwater and saltwater lakes that is an important crossroads on the Central Asian bird migration route. Its centerpiece is the massive, saline Lake Tengiz, whose shallow waters and remote islands host the world's northernmost breeding colony of the Greater Flamingo (Phoenicopterus roseus).
Each spring, beginning around April, tens of thousands of these birds arrive from their wintering grounds in Iran, India, and even Africa. In some years, the population swells to between 50,000 and 60,000 individuals. The flamingos are drawn to the lake's hypersaline environment, which supports a massive population of their primary food source: the brine shrimp Artemia salina. The carotenoid pigments in these tiny crustaceans are responsible for the birds' famous pink plumage; without this specific diet, the flamingos would be a dull grey. They build their cone-shaped mud nests on the isolated islands of Lake Tengiz, raising their young during the summer months before the long migration south begins again in the autumn.