The Cincinnati Zoo confirms hippos Fiona and Tucker are mating. The confirmation was posted in a members forum in response to questions from visitors.
Spokesperson Michelle Curley says the breeding behavior is not unexpected.
"She is at an appropriate age for this to happen," says Curley. "Tucker and Fiona, as you know, are not related. We are not trying to add another hippo to the bloat at this time, so she is on birth control."
Fiona's father, Henry, died in 2017. Tucker, father to Fiona's half-sibling Fritz, came to the Cincinnati Zoo from San Francisco in 2021.
You can see Fiona and Tucker acting playfulin this videofrom the zoo.
While it's normal behavior, Zoo Director Thane Maynard says there are concerns about Fiona mating while she's still young. Speaking on WVXU'sCincinnati Editionin September, he said "The part that makes me nervous is of course Fiona is still small. She weighs over 2,000 pounds, but she's petite and we don't want her to breed (yet). She's not cycling yet. She is on birth control, but we've proven birth control doesn't always work."
Fiona is still growing and the zoo isn't ruling out Fiona producing offspring some day, should the Hippo Species Survival Plan recommend it.
"Because she was the first premature hippo to survive, we were not sure what her reproductive future would be. We are not expecting (or hoping for) her to become pregnant now. Female hippos are often reproductively mature between 5-7, and because of that we have been prepared and expecting this day to come and Fiona has been on birth control since Tuckers arrival," writes Curley in an update to WVXU.
Curley says hippo keepers confirm Fiona "is at an appropriate age for breeding to occur and at 2200 pounds is close to the weight of some fully grown adult females."
Science, it seems, has a lot to learn about hippo birth control. Bibi, Fiona's mother, was on birth control when the zoo discovered she was pregnant by Tucker with Fritz. While Tucker was brought to Cincinnati, in part, for breeding, the pair weren't planned to begin mating so quickly.
"It's a phenomenon," Maynard said. "There's so much work done in zoos — done at our zoo and others — on reproductive biology, but we don't seem to get the dosage of birth control on hippos correct. Bibi was born by mistake at Disney's Animal Kingdom when they first opened. They had eight females and a male but all the females were on birth control so they wouldn't have too many. Well, they got the dosage wrong and they had eight babies the next year."
The zoo's hippo habitat can house no more than four hippos. Maynard reiterates that Fiona isn't going anywhere.
"She's staying; she's our franchise player."
