2011 images of the year
Lesser flamingoes at the Lake Natron at the foot of Ol Doinyo Lengai. Salmon-coloured clouds of flamingoes sweeping overhead is a common sight at east Africa's Rift Valley lakes, but the mounds of mud where they lay their eggs are found only here. The caustic waters of Lake Natron form the only breeding ground for east Africa's endangered lesser flamingoes, but the Tanzanian government is determined to revive plans to build a soda ash plant at the lake.
Check out more of this year's fascinating images from around the globe.