Hipopotamo (Sp), Nilpferd, Grossflusspferd (G), Hippopotame (F), Seekoei (Af). Also called river hippopotamus. "Hippopotamus" is from the Greek hippos (horse) and potamos (river), or river-horse.
DESCRIPTION Shoulder height 55-60 inches (140-152 cm). Weight 3,000-6,000 pounds (1,350-2,700 kg).
The common hippopotamus is an enormous, barrel-shaped, semi-aquatic animal, with short legs and almost hairless skin. The head is huge with a mouth that can open to more than 90 degrees. The canine teeth are well developed, forming tusks that are formidable weapons. The nostrils and eyes are on top of the head so that when the animal is in the water only the muzzle, eyes and ears need be visible. The skin is thick, dark and glandular, and sometimes exudes drops of moisture than contain red pigment, from which arose the supposition that hippos sweat blood. Females are similar to males, though somewhat smaller.
BEHAVIOR Highly gregarious, living in herds of up to 30, though sometimes in much larger herds. Males may be alone. Larger herds consist mainly of females and young. Adult males compete for control of herds and territories, engaging in lengthy, vicious fights-the principal weapons being their teeth-that often result in serious injury or death. Breeding occurs year-round, but with seasonal peaks in some areas. Usually one calf (rarely twins) is born 7-1/2 to 8 months later. The female will mate again two weeks after weaning the previous calf. Sexually mature at 3-4 years, but does not breed until 6-7 years. Longevity in the wild may be 40 years, in captivity as much as 54 years.
Amphibious and well adapted to living in water. A good swimmer and diver, with webbed toes to aid in swimming, and the ability to close its nostrils and ears to prevent the entry of water. Able to walk on the bottom because its specific gravity is higher than that of water. Spends the day sleeping or resting in or near water, sometimes with its head above the surface, at other times entirely submerged but coming up to breathe every few minutes. Normally stays underwater 3-5 minutes, but can remain under longer. Leaves the water at night to graze, using established paths and sometimes traveling for several miles. Will raid crops if nearby, and can cause great damage to agriculture. Entirely herbivorous, it eats as much as 130 pounds (60 kg) in a night. Senses of smell and hearing are good, eyesight is adequate. Can run surprisingly fast, and can be dangerous to man.
HABITAT Permanent deep water with low banks and nearby reed beds and grassland.
DISTRIBUTION Once found in nearly all lakes and watercourses south of the Sahara. Has been exterminated in many areas by local hunters, although still abundant in others.
REMARKS The common hippo has been extensively hunted by local people for the delicious meat, the fat (as much as 200 pounds or 90 kg per animal), the skin and the high-quality ivory of the teeth. It is not very difficult to hunt, although it certainly can be dangerous, with a history of pursuing and upsetting canoes in areas where it is hunted, and sometimes killing the occupants by biting them. A wounded hippo will often charge the boat from which the shot was fired. Hippos have been known to leave the water and charge hunters on the banks. Many natives have been killed or injured at night when they have gotten between a grass-eating hippo on land and its watery shelter. Most hippos taken by sportsmen are for lion bait (for which purpose they are unexcelled) or to fill out a collection. The trophy is the lower canine teeth, which, unfortunately, can seldom be judged in advance. Sometimes hippos are found asleep on land and are easy to collect, but most are probably shot in the water. Depending on the water temperature, a hippo that is brain-shot in deep water will rise to the surface in three to six hours.
TAXONOMIC NOTES Ansell lists four subspecies-amphibius, capensis, constrictus and kiboko-but questions their validity. We do not separate them.