Caring for Sumatran Orangutan Berani Through Kidney Disease

In 2024, Berani, the beloved 32-year-old Critically Endangered Sumatran orangutan, was diagnosed with kidney disease. Sadly, his condition has progressed to end-stage kidney failure, meaning his kidney function has declined to the point that the organs can no longer function on their own. Kidney disease is common in great apes, and our dedicated Animal Care and Veterinary Medicine teams are closely monitoring him. The average life expectancy for Sumatran orangutans in human care ranges from 30 to 50 years old.

Berani voluntarily participates in aspects of his healthcare and treatment, a testament to the incredible trust he has in our teams and the strong bonds they have formed over the years. As part of that trust and care, he takes part in voluntary blood draws, allowing our teams to monitor his kidney values. Over the past few months, our teams have noticed a fluctuation in Berani’s values and behavior, prompting them to adjust his medication as necessary.

Currently, he is stable and behaving normally. While Berani’s teams monitor his wellbeing daily, he continues to eat well, engage with his care team, and positively interact with enrichment and the rest of our orangutans. Just last week on February 15, Berani celebrated his 32^nd birthday with his mate Eirina and daughters Cerah and Siska. He enjoyed trying new fruits as part of an innovative gorge enrichment experience, a monthly event our teams have implemented to enhance our orangutans’ well-being.

Berani moved to Denver Zoo Conservation Alliance in 2017 from Audobon Nature Insitute on an Association of Zoos and Aquariums’ Species Survival Plan breeding recommendation. While he quickly became a beloved member of DZCA, he also became an international sensation who shocked the world with his remarkable caregiving instincts and caring personality. When Cerah’s mom and Berani’s mate, Nias, unexpectedly passed away in 2020 , Berani stepped in to care for Cerah—a behavior rarely seen in male orangutans. Since then, Berani has been an incredibly loving dad and it’s been amazing to watch Cerah grow under his watchful eye. Their bond remains strong, and while Cerah has naturally become more independent, she still often enjoys snuggling and spending time with dad. We anticipate that Berani’s upcoming passing could be a difficult adjustment for Cerah. Our teams are preparing to support her and the rest of the orangutans through this transition.

Although his condition is stable for now, our teams estimate Berani has a few more months before his condition worsens. Every decision regarding Berani’s care will be made with hiss best interest in mind.

As we prepare for the difficult road ahead, our teams are ensuring Berani’s final chapter is filled with comfort, dignity, and love.