Hippopotamus
Scientific name |
Hippopotamus
amphibius |
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Global distribution |
Throughout Africa south of the Sahara. However, erosion of its territory is fragmenting the animal’s range. |
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Habitat |
Deep permanent water with adjacent reedbeds and grasslands. |
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Conservation status |
Appendix 2 CITES. |
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Physical characteristics |
Body size male |
Head and body length 290 – 505 cm Shoulder height 150 – 165 cm Males are larger on average |
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Weight |
1,000 to 4,500 kg |
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Colouring |
Usual colour of the skin is a slaty copper brown, with shades to dark brown above and purplish below |
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Hair |
The body is scantily covered with short fine hairs that appear naked. |
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Piglet colouring |
Skin that is slat grey |
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Tail |
Short triangular 40 – 56 cm |
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Male side view |
Face view |
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Rear view Note short triangular tail No apparent scrotum in the male |
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Female side view |
Face view |
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Rear view |
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Drinking pattern in Portugal Zoo |
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Anatomical points |
Peculiarities |
Nostrils are carried on top of the snout. The nostrils can be closed. The eyes are set high up and protrude. Skin contains special glands that secrete a pinkish substance known as “blood sweat” Skin contains a large amount of fat. The skin must remain moist or it will crack. The foot bones are separate and all toes support weight. The terminal digital bones have nail-like hooves Stomach is complex with three chambers, but it is non-ruminating. |
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Track of a hippo Note weight on all four digits and heel pad |
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Fore limb digits detail |
Hind limb digits detail |
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Plantar surface of the hind foot. |
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Glands |
Skin glands produce ‘blood sweat’ |
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Dental formulae |
(I 2-3/2-3, c1/1, pm 4/4 m 3/3) x 2 = 40-42 Upper canines may measure 230 mm The lower canines may reach a length of 700 mm, of which 300 mm is above the gum line and they can weigh as much as 300g. The mouth can open to 150°. |
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Skull face view |
Skeleton side view |
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Behaviour points |
Maturing age |
In captivity 3-4 years. Females in the wild about 7-15 years |
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Mating ritual |
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Dominance ritual |
Bulls which do not back down easily, will approach each other with mouths jaws, scoop water up into their mouths and spray it high in the air. Usually there is no contact, but sometimes the lower jaws are slammed together and serious fights will develop. |
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Seasonal breeding |
Seasonally polyoestrus. In some areas there are peaks in breeding with births occurring at times of maximum rainfall. Interval between births often 2 years |
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Oestrus period |
Lasts 3 days. |
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Gestation period |
227- 240 days |
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Litter size and lactation |
Single occasionally twin calves. |
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Birth weight of 25-55 kg |
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Lactation |
Weaning at 6-8 months |
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Weaning age |
6 to 8 months |
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Family groups |
May live alone or in large groups of up to 150 individuals. Normally 10-15 are found in a group. Most of the group will be female. Groups may be dominated by a bull male. Territories may be marked by defecation piles. |
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Cooling behaviour |
The Hippopotamus spends most of the day in water |
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Hippos in the water |
Hippos below water |
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Peak activity |
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While the hippopotamus is amphibious, it is actually a poor swimmer. |
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Normally only stays submerged for 1-3 minutes but can stay submerged for 30 minutes at a time. |
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Buoyancy is such that the Hippopotamus can walk around on the body of the river |
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Range |
The Hippopotamus may travel over 33 km a night in water in search for food |
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Grazing range may extend 3.2 km from the water |
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Population density can be very high locally, reaching 19.2 sq km. |
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Senses |
Hearing, sight and smell are all well developed. |
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Diet |
Mainly grass and vegetation, cropped by the action of the horny lips It requires about 1-1.5% of its body weight for maintenance. Its metabolic rate is relatively low. The Hippopotamus spends about 5-6 hours a day grazing. In a single night it can eat about 100 kg of water plants and destroy almost the same amount by standing on it. |
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Diseases/ disorders |
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Age |
In the wild about 41 years. In captivity 61 years. |
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