The staff at Franklin Park Zoo is saddened to report that Christopher the lion was humanely euthanized today.

The 21-year-old lion was being closely monitored and treated for several irreversible age-related issues over the past two years. These included declining kidney function, chronic cystic disease of the liver, and arthritis. Due to his continued declining health in recent weeks, the Zoo staff made the decision to humanely euthanize him for quality of life reasons.

“The veterinary and animal management staffs took extraordinary care of Christopher as his age-related issues mounted. With our older animals, we do everything we can to ensure they enjoy a comfortable life as they continue to age, which is often far longer than the median life expectancy,” said Dr. Eric Baitchman, Zoo New England Director of Veterinary Services. “As Christopher aged, his dedicated zookeepers continued to utilize the well-established training programs. This played an integral role in assisting the animal management and veterinary staffs in closely monitoring his health, and developing and carefully refining treatment plans. Christopher will be greatly missed by so many.”

The median life expectancy for lions in captivity is 16.8 years. Christopher, who turned 21 on July 22, 2014, was among the oldest lions within the North American population.

“He will be deeply missed by staff as well as the many visitors who came to see him throughout the years. He was an incredible ambassador for his species and people were drawn to his impressive roar, which could be heard throughout the zoo. Perhaps the only thing more impressive than his roar was his imposing physical presence. Christopher truly was the king of the Franklin Park Zoo,” said John Linehan, Zoo New England President and CEO.

Christopher had lived at Franklin Park Zoo since 2001 after arriving from Lion Country Safari in Florida where he was born.