Kamaia, a 14-year-old lion at Boston's Franklin Park Zoo, was humanely euthanized on Saturday following a decline in health, Zoo New England announced on Sunday.
According to Zoo New England, Kamaia had battled several health issues, including pneumonia, as well as chronic health issues.
Kamaia underwent successful surgery and blood transfusion from his brother Dinari back in June.
An exam had discovered that Kamaia was severely anemic and had a greatly enlarged spleen. He then underwent a second surgery to remove a hernia at the surgery site.
"Kamaia was an incredible ambassador for his species, and we are deeply saddened to share the news of his passing," John Linehan, president and CEO of Zoo New England said in a written statement.
Kamaia had been at Franklin Park Zoo since 2015.