The hide is rough and scaled. Juvenile Nile crocodiles are dark olive to brown with darker crossbands on tail and body.
Adults are uniformly dark with darker crossbands on tail.
A female can lay 25 to 100 eggs, which she covers with sand, then guards until they hatch 3 months later. Other prey items may include zebras, hippos, porcupines, pangolins, and migrating widebeest. A crocodile's ectothermic metabolism is extremely efficient. When fish are migrating, crocs may hunt cooperatively by forming a semi-circle across the river and herding the fish. They then eat the fish that are closest to them.