Fiona the Hippo Is a Big Sister! Cincinnati Zoo Star's Mom Bibi Gives Birth to Second Baby

Fiona the hippo is finally a big sister!

The Cincinnati Zoo confirmed in a news release on Thursday morning that Fiona's mother, Bibi, gave birth to her second hippo — a healthy, full-term calf, born Wednesday at 10 p.m. local time.

According to Christina Gorsuch, the Cincinnati Zoo's director of animal care, the new baby hippo weighs at least twice as much as Bibi's first calf, Fiona — who was born six weeks premature in 2017 and was not able to stand on her own as a newborn.

"We're not sure if nursing has occurred yet because the water is murky," Gorsuch said. "It's Bibi's first time nursing, since Fiona had to be cared for by the hippo staff, so we're keeping a close eye on them to make sure we don't need to step in."

The zoo went into a 24-hour baby watch on Tuesday when it said its hippo team "noticed a difference in Bibi's behavior." The zoo said in a statement Thursday that her behavior appeared consistent with going into labor.

RELATED: Cincinnati Zoo Under 24-Hour Baby Watch as it Waits for Fiona the Hippo's New Sibling to Arrive

Cincinnati Zoo/Twitter

"Bibi and the baby, yet to be named, will spend the next two weeks bonding behind the scenes," Gorsuch said in the zoo's news release.  "A female would take her newborn away from the bloat for about that amount of time in the wild, and we try to give Bibi the choice to do what feels natural to her."

While Bibi and the newborn hippo get time to themselves to bond, Fiona and another resident hippo, Tucker, are growing used to hanging out on their own, the zoo wrote in a news release.

"Keepers have been separating them from Bibi periodically over the past weeks to get them used to being a duo," the zoo wrote in a statement. "They're so comfortable with each other now that 2000-pound Fiona has been seen napping on 4500-pound Tucker."

The Cincinnati Zoo said its animal care team will take photos and videos of Bibi and her new baby for the zoo to share if and when they are able to do so without disturbing the animals. For visitors hoping to spend time observing the zoo's famous hippos, 19-year-old Tucker and Fiona will still be in the hippos' outdoor habitat "except during key introduction times," the zoo said.

Cincinnati Zoo & Botanical Garden

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Interested hippo spectators with Cincinnati Zoo memberships have access to live cameras in the hippo habitat that operate live from 8:30 a.m. to 5:00 p.m. every day, according to the zoo's statement, though it noted that cameras may be turned off during animal introductions or if the animal team requires privacy.

Bibi was expected to give birth in mid-August, but the hippo's birth window could have been 30 days before or after the estimated due date, so the zoo was prepared for Fiona's sibling to arrive at any moment.

In July, the Ohio zoo shared an update on Instagram about the upcoming hippo baby.

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"According to measurements made during Bibi's last ultrasound, her fetus is bigger than Fiona was when she was born!" the Cincinnati zoo shared. Bibi's first baby, Fiona, was born six weeks premature and wouldn't have survived without the intervention of zookeepers. Fiona's resiliency and continued success have made her a star at the Cincinnati Zoo.

Cincinnati Zoo & Botanical Garden

When Fiona was born in 2017, she only weighed 29 pounds, 25 pounds less than the lowest ever record weight for her species. Ahead of her sibling's arrival, Fiona celebrated one of her own accomplishments.

"Fiona finally hit 2,000 pounds! She weighed in at 2,036 pounds this morning!" the zoo shared on Instagram in July. "We're so proud of how far she has come! 🦛🎉🎉🎉 #TeamFiona"

The Cincinnati Zoo initially announced Bibi's pregnancy in a release in April. Tucker, the new calf's father, arrived at the Cincinnati Zoo in September 2021 by way of the San Francisco Zoo, and Bibi and Tucker bred in December 2021, according to WWLT 5.