The migratory herds are moving back to the Serengeti in Tanzania. Here is a herd of wildebeest and zebras crossing the Mara River. We watched them mill about for hours before they chose a crossing and got the courage to jump in the river. Just downstream is a large group of crocodiles waiting for them. This herd made it across with no casualties, but a few fraidy-cat zebras stayed behind (lower left).