A surprise hippo pregnancy? Hippopotamus at the Cincinnati Zoo welcomes baby, despite being on birth control

Collective "awwws" can be heard around the world as the most famous family of hippos welcomed a baby calf at the Cincinnati Zoo and Botanical Garden. Until the 60-pound bundle of joy arrived, the zoo's famed bloat — a term for a group of hippos, inspired by their bloated bellies — consisted of mother, 23-year-old Bibi, daughter, 5-year-old Fiona, and 19-year-old Tucker, who joined the group in 2021. Mother and new baby are healthy and well, the zoo shares.

The adorable family was first catapulted onto the global arena — and won over the hearts of many — when Fiona was born prematurely. Luckily, she survived, thanks to the intervention of human caregivers, and is now enjoying a healthy adolescence. The family's newest bundle of joy, yet to be named, arrived weighing at least 60 pounds and is already walking.

The zoo first learned of the pregnancy around April Fool's Day and initially thought it was a timely joke since mom Bibi was on birth control — but Mother Nature had other plans. A healthy, full-term baby hippo arrived in the late evening of Aug. 3, further solidifying that it was indeed not a joke.

?"This calf looks huge to us because Fiona, Bibi's first baby, only weighed 29 pounds when she was born six weeks premature and wasn't able to stand on her own," said Christina Gorsuch, the Cincinnati Zoo's director of animal care, in a press release. "This new calf weighs at least twice as much as Fiona did and is already walking."

At the time of the press release, Gorsuch shared they were unsure whether or not Bibi was nursing due to the murkiness of the water in the hippopotamus' habitat. "It's Bibi's first time nursing, since Fiona had to be cared for by staff, so we're keeping a close eye on them to make sure we don't need to step in," she explained.

In a later post to the zoo's Instagram account, it was reported that nursing is going well. "The newborn hippo has spent most of the day in the indoor pools with Bibi, exploring, resting and nursing, which is exactly what the hippo care team was hoping for," the post states. "Hippos spend most of their lives in water and hippo calves even nurse underwater."

The healthy pregnancy was a sigh of relief for zoo staff as Fiona was born six weeks premature and too weak to reach Bibi for nursing. For this pregnancy, Bibi received ongoing hormone supplements and regular ultrasounds to monitor the calf's growth and health.

Bibi and her baby will spend the next few weeks behind the scenes nursing as 19-year-old brother, Tucker, and 5-year-old sister, Fiona, await the meeting of their new sibling. The zoo shared that the brother-sister duo are so comfortable with each other that 2000 pound Fiona is often spotted napping on 4500 pound Tucker.

For now, mom and baby will be hidden from the public, but Tucker and Fiona will remain visible in their usual outdoor habitat.

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