Middle Wilds of Africa keeper Jessi Vigneault guest-blogs on Zoohoo!
Just as if you were to put groups of Longhorns and Aggies in a room, getting a nyala herd to coexist peacefully with a sounder of red river hogs can have its challenges, especially when males are involved (sorry, guys).
The Dallas Zoo wanted a new home for its male and two female red river hogs, and the nyala antelope habitat had some extra room to share. Both are African species, although they inhabit different parts of the continent. This new pairing required habitat modifications, new animal training, and a slow, very closely monitored introduction. Ultimately, it would be up to the animals to decide if it would work or not.
The habitat was great for our bachelor herd of four nyala, but it wasn’t quite ready for the rooting and digging habits of hogs, so underground rebar was added to reinforce the fencing. A log and rock barrier was built around the exhibit’s large pond, to prevent the hogs from falling in. And we constructed a concrete drinking bowl for the hogs, because they tend to play with anything light enough to move, including rubber water bowls.
A nyala and red river hog share an inquisitive moment on the first day of face-to-face intros. (Image: Mammal Curator Keith Zdrojewski)
With the habitat ready, we worked on avoiding possible conflict at the gates when the animals “shifted” in and out between the exhibit and their night quarters. We ring a bell and reward the nyala with their favorite treats at the bottom of the exhibit. They quickly learned to come toward the bell when rung. This training provided us a method to pull the nyala away from the top shifting gate when the hogs would be let through.
The next step of the introduction was getting the hogs comfortable and familiar with the area before meeting the nyala. Using a corral made of cattle panels covered with boards and wire mesh, the habitat was divided in half and the hogs were given time to acclimate to each side. We introduced them to their own shifting cue by honking a horn and rewarding them when they shifted in and out.
Though the hogs and nyala can see each other in their night quarters, we also gave them a chance to see and smell each other up close with the protection of the corral. We believed this interaction would give some indication of how the two groups would co-exist. There was some interest from both groups, but no aggressive behaviors were observed, and they soon ignored each other. This was a good sign, so we decided to move forward.
Log piles and large branches were placed around the habitat, so animals being chased would have something to put between them and their pursuer. The corral panels were removed to open the space up so individuals couldn’t be trapped.
It can be hard to predict how animals will react during new introductions and we always prepare for incidents, but this went extremely well. There were a couple of brief disagreements, but no chasing or serious altercations. As a result, the hogs now enjoy spending time in a new home with new friends.
Letting the animals become accustomed to their new surroundings and the sight and smell of other animals before putting them together help ensure successful introductions, and we greatly appreciate the patience of our visitors during this process. Next time you visit the Dallas Zoo, be sure to ride the Adventure Safari monorail and see how the nyala and red river hogs are doing together!