July 18, 2019

The Pride of Denver Zoo

Vice President for Animal Care Hollie Colahan Plays an Important Role in Lion Conservation in Zoos Across North and Central America and in the Wild

By Carlie McGuire, DZTV Host  


On the wall of Hollie Colahan’s office is a large grid filled with red and blue dots representing the male and female African lions in zoos across North America and Colombia. This at-a-glance reference is key for Colahan, who manages the African lion populations in Association of Zoos and Aquariums (AZA) zoos. As the Species Survival Plan (SSP) Coordinator, Colahan works with AZA-accredited zoos to determine which lions would make ideal breeding pairs and helps zoos manage their lion populations. Being SSP coordinator means more than shuffling around blue and red magnets from square to square.  

“It’s my job to ensure that the population of lions in human care is genetically diverse and healthy. To do that, we have a database with detailed information about every lion in AZA zoos. We know their parents, where they live, their age, how many offspring they’ve already had,” said Colahan. “We also consider potential compatibility between lions. I’ve worked with lions since 1997, they’re a social species, and not every lion is going to get along.”  

The Lion SSP began in 1993 in response to a declining number of lions in AZA-accredited institutions but has turned a corner over the last several years, leading to an all-time high number of lions in zoos—more than 370 animals across 105 facilities. In 2018, the Lion SSP received the SSP Sustainability Award for accomplishing the AZA’s goals for a healthy population and top-quality care for lions. 

Maintaining healthy population within zoos isn’t Colahan’s only goal. She also serves as Program Leader for the African Lion SAFE (Saving Animals from Extinction) program. The International Union for Conservation of Nature currently lists African lions as a vulnerable species, with a decreasing population. Colahan and Denver Zoo partnered with the Los Angeles Zoo, Disney’s Animal Kingdom, Omaha’s Henry Doorly Zoo and the Lion Recovery Fund to increase the number of lions in the wild.  

“I don’t think most people realize what’s been happening to the African lion population in the last 25 years. Since 1994, we’ve lost half the population of African lions for a variety of reasons like loss of habitat and human conflict,” said Colahan. “Lions are such a well-known species and people don’t want to hear bad news about an animal they love. They’re strong and iconic, and no one wants to think of them as in trouble. 

With the spotlight on all things lion this summer, Colahan hopes people around the world take the chance to learn what they can do to help this iconic species. For people in Denver, that can start with a visit to Denver Zoo where they can learn about the two prides we have here and about the other African species we have in our care. 

“It’s going to be a team effort to reverse this trend, and people are the key to saving this species, so we’re hopeful that together, we can find solutions that benefit wildlife and people." said Colahan.

Sometimes, Colahan’s work as SSP Coordinator and Vice President for Animal Care overlap. It was Colahan’s recommendation that brought 3-year-old Tobias from Buffalo Zoo to Denver Zoo in December 2018. Tobias joined our three females, Neliah, Kamara and Sabi – and after a long introduction process – fully integrated with the pride earlier this year. Colahan says Tobias is an ideal candidate to pair with Neliah (age 7) and Kamara (age 3). 

“Tobias’ genetics are valuable for the SSP because he doesn’t have too many relatives in zoos and no relation to any of our females,” said Colahan. 

Tobias and our females have gotten along so well that Neliah welcomed a cub in late July which you can read all about here! Be sure to follow us on FacebookTwitter and Instagram for updates on our pride! 

World Lion Day on August 10th

Celebrate World Lion Day with Denver Zoo’s prides! Join us for an exploration into the world of lions and the amazing animals who share their precious ecosystems.


Be among the first to hear the latest animal updates, important stories and details about all the fun happening around Denver Zoo.


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