The ability to stay on her feet to nurse is a big factor animal care staff will weigh to determine when Fiona can be reunited with Bibi.
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When she was born Jan. 24, the calf weighed just 29 pounds – about 25 pounds lighter than the lowest recorded birth weight. The normal birth weight for the species is 55-120 pounds.
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The Nile hippo, also known as a river hippo or river horse, can grow to 4,000 pounds, on a vegetarian diet. Although hippos spend much of their day in the water, they actually can’t swim, but move by floating or walking along the water bottom, according to the zoo.
Donations can be made to help cover the cost of the round-the-clock critical care Fiona requires.