Wildebeest great migration

The Blue wildebeest in Tanzania is best known for its part in the great migration. Moving roughly in a circle from the Serengeti in Tanzania to the Masai mara in Kenya, it congregates in large herds guided by the weather which signals where food is abundant. Something as small as a light evening rain can move the entire herd from one area back to where they were the night before. When they are present, the herd appears to stretch for as a far as the eye can see. River crossings cost many of lives and they often cross back and forth several times in a season