Fiona the hippo, the calf born prematurely at the Cincinnati Zoo, has been making steady progress in her development. She's done well with her pool exercises, and she's closing in on 150 pounds! The next big challenge? Getting comfortable with the indoor pool that her mom and dad use!

The video above shows Fiona going for her first "adult swim," albeit in a significantly drained pool. The purpose of the swim is to help Fiona master diving and then propelling herself up for air. According to the zoo's Fiona blog, "Hippos are capable of taking in deep breaths of air to inflate their lungs and increase their buoyancy in the water to combat the density that causes them to sink." From the video, it looks like she's getting the hang of it!

Fiona's keepers hope to move her to an outdoor pool in May, once the warm weather is here to stay. In the meantime, they're working to prepare her for her celebrity status — her keepers have minimized her exposure to humans for her health's sake — by slowly conditioning her in positive ways as she deals with more humans. Along similar lines, keepers have been working to integrate Fiona with her parents, Bibi and Henry. The results, on both the parents' side and Fiona's side, have been mixed at best, so the care team is going slow and hoping for the best.