Overview
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.
Taxonomy
- Kingdom
- Animalia
- Phylum
- Chordata
- Class
- Mammal
- Order
- Artiodactyla
- Family
- Hippopotamidae
- Genus
- Hippopotamus
Habitat
Permanent deep water with low banks and nearby reed beds and grassland.
Diet
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.
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. Senses of smell and hearing are good, eyesight is adequate. Can run surprisingly fast, and can be dangerous to man.
Hunting
The common hippo has been extensively hunted by local people for the delicious meat, the fat (as much as 200 lbs (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. 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.
Conservation Status
Listed as Vulnerable by IUCN. The 2008 Red List Assessment described the Common Hippopotamus (Hippopotamus amphibius) populations as Vulnerable, as the population experienced considerable declines in the mid 1990s and early 2000s. The most recent population estimates suggest that, over the 8 years since the last assessment, Common Hippo populations have largely remained stable. The 2008 Red List Assessment estimated Hippo populations to be approximately 125,000 and 148,000, with half of the 29 countries in which Common Hippos were found reporting declines. Our current assessment yields a lower population estimate, on the order of 115,000-130,000 Hippos. However, we believe that the observed downward shift in total population size likely reflects overestimated population sizes from some countries in the 2008 Red List Assessment that have now been corrected. Because of this, a change in the Risk Category classification of Common Hippos is not warranted at this time. The conservation status of Hippos remains precarious and the need for direct conservation action to protect Hippos and Hippo habitat across their range is a priority. Although in some countries Hippo populations have stabilized, Hippo population declines are still reported in many countries. The growing and unabated threats of habitat loss and unregulated hunting are major challenges to Hippo population viability and persistence. (IUCN)