San Diego Zoo Celebrates Its First Endangered Pygmy Hippo Birth in 30 Years

This big boy's birth was a momentous day for one zoo.

On Friday, the San Diego Zoo announced that on April 9, their 4-year-old pygmy hippopotamus named Mabel welcomed a male calf — the zoo's first successful pygmy hippo birth in more than three decades.

The yet-to-be-named baby weighed in at 12.4 lbs. and began standing and walking alongside his mom within his first few hours on the planet.

"Mom and calf are doing very well ... and the calf is nursing and getting lots of attention from the first-time mother," the California zoo said in a statement.

Zookeepers said that today, the calf — which now weighs about 25 lbs. — is "meeting and surpassing the milestones that wildlife care specialists watch for in a young pygmy hippo, including the ability to go underwater."

"To prepare the calf for exploring in the water, wildlife care specialists placed a small, shallow tub in the indoor habitat," explained the zoo. "When mom and her calf were given access to the outdoor maternity habitat, staff added a fence to prevent the calf from venturing into too-deep water."

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Ken Bohn/San Diego Zoo

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They added: "The calf demonstrated the natural adaptations and instincts of pygmy hippos — to close their nostrils and to hold their breath underwater — and today, both Mabel and the calf have full access to the pool in the maternity yard."

Ken Bohn/San Diego Zoo

Footage released by the San Diego Zoo shows the adorable, big-eyed calf swimming, dunking his head underwater and staying nearby his mother.

According to the zoo, the calf will not be introduced to his father since the animals "do not live in family groups, and males do not play a role in the rearing of offspring."

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Ken Bohn/San Diego Zoo

Pygmy hippos are found in rivers throughout the forests of West Africa, specifically four countries: Côte d’Ivoire, Guinea, Liberia, and Sierra Leone. As many as 2,500 of the animals remain in Africa, according to the zoo, which notes that logging, farming, and human settlement affect the species' population.

The species is currently listed as "endangered" on the International Union for Conservation of Nature Red List of Threatened Species.