Celebrating 130 Years—Together

Pop Quiz!

How would you describe our new Cape buffalo calf?
A) So silly
B) So cute
C) So good at having bottom teeth
D) The embodiment of "you got any games on your phone?"
E) All of the above

📸: Lead Animal Care Specialist Megan G., Kim D. and Animal Care Specialist Laura W.

We are heartbroken to share that Rudy, our beloved 32-year-old black rhino, was humanely euthanized on Tuesday, May 26.  
 
Earlier this month, we shared that Rudy entered end-of-life care as his age-related mobility challenges and chronic health conditions continued to progress, including Iron Overload Disorder, a condition that can impact vital organs and overall immune health.  

Despite the dedicated efforts of his Animal Care and Health teams and the additional support measures put in place to keep him comfortable, his quality of life continued to decline.  
 
As difficult as this decision was, our teams remained guided by our commitment to animal wellbeing. We never want an animal’s last day to be their worst, and together, Rudy’s care team made the compassionate decision to humanely euthanize him to honor that goal. He passed peacefully, surrounded by those who loved and cared for him. A postmortem exam will help us better understand the factors that contributed to his decline and contribute to the continued scientific knowledge that supports black rhino care and conservation worldwide.  

Throughout his final weeks, Rudy showed incredible resilience and trust. He voluntarily participated in many aspects of his healthcare—including blood draws to help monitor his IOD—reflecting the deep bond he shared with his team after nearly 10 years at DZCA. Our Animal Care and Health teams worked diligently to adjust treatments and closely monitor several quality-of-life indicators, ensuring his final chapter was filled with comfort, dignity and love.  
 
 
Thank you to everyone who played a role in Rudy’s care and wellbeing throughout his life, and especially to the Animal Care and Health teams who supported him through his final chapter with extraordinary compassion, dedication and love. Many of us had the privilege of knowing Rudy in different ways, but all of us benefited from his presence.

We invite you to honor Rudy’s memory by sharing your favorite moments, photos, and stories in the comments. You can also read more about his life and reflections from his dedicated care team by visiting the link in our bio.

Earlier this spring, our Great Plains Field Conservation and Veterinary Medicine teams joined @denvermountainparks, @csuvetmedbiosci, and Lewis TallBull for two important bison immobilization field days at Daniels Park.

This collaboration helps us monitor and care for one of the oldest bison herds in Colorado. During the field days, two bulls and two cows received GPS collars; the rest of the herd was outfitted with lightweight GPS ear tags to help monitor their movements as they explore a new pasture on Highlands Ranch Backcountry Wilderness Area (HRBWA). The collars provide location updates every 15 minutes, while the ear tags report hourly, allowing teams to respond quickly if a bison wanders outside designated areas. Tracking information will also help us better understand grazing behavior and inform pasture management.

While the animals were briefly immobilized to place the tracking equipment, our Veterinary Medicine team collected DNA and other health metrics to assess the herd`s overall wellbeing and genetic lineage.

The long-term goal of this work is to help restore bison to their native grasslands. Daniels Park and HRBWA provide an ideal landscape for expanding bison habitat as one of the few untilled prairie ecosystems in Colorado.

Photos: Volunteer Photographer, Scott Dougherty and Great Plains Conservation Program Director, Kate Wilkins