Hippopotamus live in the rivers, lakes, and swamps of the continent of Africa, south of the Sahara Desert. Even though hippos spend most of the day submerged in the water, they move out on dry land at night to feed on green grasses and other plants growing nearby. Male hippos can grow to 11 feet long and weigh up to 7,000 pounds. The smaller females seldom exceed 3,000 pounds. Hippos have a barrel-shaped body, stubby legs with webbed toes, and a large, heavy head with small ears and bulging eyes. Only whales have larger mouths than hippopotamuses. Los Angeles Zoo.