Dozens of hippopotamuses are stuck in mud in a shrinking pool in a game reserve in Namibia, and are at high risk of dying of dehydratation and hunger, the Daily News online publication reported on September 5. The animals should stay in water or mud to protect themselves form sun and heat only daytime, but they need to swim in water during reproduction and childbirth, and they have to they emerge at dusk to graze on grasses. The flock stuck in the mud has no more water to drink and is not able to get out for graizng neither.

The pool, in the Wuparo Conservancy about 900 km northeast of the capital Windhoek, was dependent on flows from a nearby river but a prolonged drought has dried up the source, the newspaper said, quoting the manager of the nearby Livingstone wildlife camp.

Several hippopotamuses have been stuck for months in the pool. More than 40 are believed to be there now, the manager said.

Hippopotamuses, or commonly named hippos, are large, mostly herbivorous, semi-aquatic mammals native to sub-Saharan Africa. Nowadays hippo is the third-largest type of land mammal that inhabits rivers and lakes.

However these impressive animals, which are now only found in Africa and Asia, once upon a time roamed also in Europe.

The scientists discovered their remains in Greece in Pinios river valley, attributing to the Upper Pleistocene era, which began 180,000 years ago and includes a vast swath of human history, ending just 10,000 years ago, when humans had begun to form settlements.