Although many species have gestation periods so brief that they're over seemingly in the blink of an eye, hippopotamuses are definitely not among them. The gestation periods for the two hippopotamus species that roam the Earth today last for many months.
Length of Common Hippopotamus Gestation
Gestation for the common hippopotamus (Hippopotamus amphibius) typically lasts for around 8 months, a mere month less than the typical human pregnancy. Although common hippopotamuses are pregnant for shorter periods of time than human beings, their calves exit the womb significantly bigger than newborn humans -- roughly 10 times so, according to Animal Bytes of the San Diego Zoo.
Common Hippopotamus Birth
Common hippopotamuses generally bear young once every two years or so. When a mother is ready to give birth, she generally removes herself from her herd for a week or two. With this time away from the rest of the group, the mother can work to establish a strong connection with her calf. Hippo calves are often born in shallow underwater environments, which is where nursing often takes place, too. However, it's not uncommon for birthing to occur on land.
Length of Pygmy Hippopotamus Gestation
Although pygmy hippopotamuses (Choeropsis liberiensis) have a lot of similarities to common hippopotamuses, they are considerably smaller. Hippos in this species not only mature faster than common hippopotamuses, their gestation stages are shorter. The gestation of a pygmy hippopotamus typically lasts six to seven months.
Pygmy Hippopotamus Birth
Like common hippopotamuses, pygmy hippopotamuses usually give birth to one calf at a time -- no large litters in hippo land. Twins are not common, but they are possible. But unlike common hippos, pygmy hippos always give birth on dry land. For the first several weeks of a pygmy hippo calf's life, the mother keeps it safely concealed amidst shrubbery. At this young and tender stage, the calves simply can't walk properly.
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