Taking care of the my zoo’s hippos the other day, I had a pretty cool experience with one of our girls. We have two hippos. One is considered geriatric while the other is considered a teenager. Everyday we do a “Hippo Chat” where I, the keeper, go out to the exhibit and chat about our hippos to our guests. I really enjoy doing it. It’s very rewarding when the hippos and people engage. It’s fun seeing people’s faces light up when I tell them an interesting fact and when the hippos participate, everyone has a good time.
The other day, at my chat, our teenager was the only one to come out of the water for treats. It took her a while. Usually the girls will circle in the pool before one of them decides to come out. I could tell our teenager wanted treats, but our older hippo kept blocking her path. Eventually, our teenager gives a little display: opening her mouth and doing a partial porpoise before she raced out of the water. I was able to call her over and she enjoyed some of my bananas while guests gawked at her. I like to show off our hippos and how good they are, so I asked our teenager for some training cues. She did a fantastic job and after a couple more banana slices, she decided she was done. She didn’t go back into the water which made me hopeful that she’d come back.
I’ve noticed with our teenager that she’s gotten into the habit of searching for browse after participating in the hippo chat. She’ll wander around the edges of the exhibit to see if she can spot any branches or leaves she can reach through the exhibit bars. She didn’t find any, but she did find a nice sunny patch to stand in on that cool, fall day.
By now, the guests were coming and going. With one hippo snoozing in the water and other enjoying a sunny patch on the far side of the exhibit, I wasn’t surprised people weren’t lingering to watch them. Those that left, well, they certainly missed out.
Our teenage hippo decides to come back closer to the front of the exhibit. She has to climb a little, rocky hill then she’ll be on a big pit of sand. She reached the sand and charged.
Our rowdy girl tossed her head and charged me at the bars of the exhibit with mouth open wide. I didn’t move. The bars are six inches thick and she knows how hard they are. She stopped short, tossed her head again, then circled the sand pit in a trotting display. She was acting tough. The head bobbing, the tail flicking, and the strutting about were clear signs she’s was letting everyone know she’s a queen bee.
I’m not used to seeing her in this feisty mood. She’s always been so sweet, but she is a teenager coming into maturity. When animals come into maturity, they have to figure out how to fit into their society. Will they rise the ranks closer to alpha or hang out on the bottom of the totem pole? Our teenager lives with one other hippo. A hippo that is much older than her. She may not be able to show our other hippo who’s boss–during her little display, the other hippo didn’t care. She napped the whole time–but there are others our teenager sees every single day that thinks she can boss around.
From my experience, as long as zookeepers don’t react to the animal displaying at them, then the animal will get bored and eventually stop. Animal behavior is fascinating to me and our feisty teenager’s display got me curious on deeper behaviors of hippos. Unfortunately, I’m not finding a lot of scientific articles about hippos that I have access to (a lot of institutional sites require a login). However, I did find a study done in 2009 about social structure of captive female hippos. A scientist studied the hippos at Disney’s Animal Kingdom for several months. Hippos are known to be social animals, but she wanted to do deeper than that. She discovered that hippos prefer familiarity when interacting with other hippos. They’ll hang out with kin over other hippos and if they don’t have kin, then they’ll hang out with the hippo they’ve known the longest over other hippos. It makes sense. The longer you know someone the easier it is to anticipate what they’ll do or allow.
Our hippos at the zoo have only been together since 2019. They met when our teenager was still considered a child and our older hippo took on a maternal role for her. I’m hoping the bond between them back then will be strong enough to survive the teenage years. Although, I don’t blame our older girl for losing her patience when the teenager constantly pokes her in the face when she’s trying to nap.
All in all, our hippos are doing great. Our teenager is still in the early years of maturity, so she’s got a while before she figures herself out. In the meantime, she’ll probably keep testing us zookeepers. I certainly hope I’m around to watch our girl grow.