March 29, 2019

A Match Made in Denver

How Denver Zoo Keepers are Preparing Tobias to Join Our Resident Lioness Pride 

By Molly Kainuma, Predator Keeper 


You may have heard about our newest arrival to Benson Predator Ridge, a three-year-old male African lion from named TobiasHis move from Buffalo Zoo to Denver Zoo came at the recommendation of the Association of Zoos and Aquariums’ Species Survival Plan (SSP), and his addition brings our resident lion population to eight total individuals. Tobias will soon join a pride with three females while our male coalition of four brothers will continue to live separately. I’m often asked about how we introduce our animals when we have new arrivals, so here’s a quick sneak peek at what’s been going on behind the scenes:  

Careful Planning 

When it comes to lions, it’s not as easy as having your two house cats meet. It’s a process that can take a while because we need to make sure each lion is ready and comfortable before they can even be in the same space together! These introductions depend on several factors, like the individual personalities, history, social structure and behavior of the animals involved. Socially-housed animals like lions require a carefully thought-out plan from the animal care team. Zookeepers and managers work closely to develop a step-by-step method for how we will proceed, and the behaviors we are looking for that inform when to move forward.   

First Things First 

In early March, we started the introduction process between Tobias and our three females—Neliah (age 6), Kamara (age 3) and Sabi (age 6). The SSP recommendation is for Tobias to breed with only Neliah and Kamara, but we also want to know that Tobias will be respectful of Sabi, as she is our smallest lion and has a unique social and health history.  

Howdy Y’all 

First, we introduced Tobias to his holding spaces and exhibit yards. Predator Ridge is a large exhibit, and we wanted him to get used to these spaces before giving him the opportunity to see the females from a distance.  From there, we moved towards visuals in closer proximity to one other and worked our way up to what we call a “howdies”—a process where the animals are separated by a mesh door, so that they can see, smell, and interact, but not physically share space. At this point, Tobias has had visual access to all three female lions in stalls next to each other. So far, so good! We continue to see positive interactions, which include vocalizing or calling to one another, cheek-rubbing through the mesh, choosing to position themselves closer together and relaxing or eating comfortably in each other’s presence.   

Paws-itive Signs 

When we see enough positive interactions between the individuals, we’ll feel comfortable moving forward with physical introductions. In groups with multiple individuals this process may be repeated with each individual animal or done all at once.  There is some strategy behind who we may want to see have stronger bonds with one-another.  In our situation, Tobias is recommended to breed with both Neliah and Kamara. If possible, it’s usually to our advantage to time this process when the females are cycling so they are more receptive to a new male.   

It’s important to know that introductions are a process and the animals’ comfort levels and behavior dictate how quickly or slowly we move things along.  This could take days, weeks, months or, believe it or not, even years! We can’t wait to have our pride together and on exhibit for our guests to see, but in the meantime wanted to give you a sneak peek of what is going on behind-the-scenes of a successful introduction process.  


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