Formerly, there were as many as two million flamingos at Lake Nakuru, in Kenya, Africa. They blanketed the lake's entire surface.
However, at present, they are hardly ever seen. The reasons are that the water level of the lake has risen abnormally, and the flamingos can no longer find algae, their food.
It is conceivable that the rise of the water level at Lake Nakuru is caused by the following: due to development around the lake, forest areas have decreased, which in turn has led to a loss of the water retention function of soil. Such changes in the natural environment are often brought about by the international ideal of prioritizing economic activity.