Veterinarians at SeaWorld euthanized a 35-year-old bottlenose dolphin that had an aggressive oral cancer.

Lily was diagnosed in 2010 and was treated by the SeaWorld vet team. They made the decision to end her life after her health declined.

“While this type of cancer cannot be effectively cured, our team explored every option to assist Lily and stayed focused on her quality of life,” said SeaWorld spokeswoman Aimee Jeansomme Becka in an email. “Sadly, her condition recently deteriorated, and the decision was made to humanely euthanize her based on her very poor prognosis and in consideration of her quality of life.”

Lily had lived at SeaWorld since 1992. She was captured on August 13, 1983 and lived at the New York Aquarium until 1991. She spent a year at the National Aquarium in Baltimore before being moved to Orlando.

Bottlenose dolphins live between 30 and 50 years. A study comparing dolphins in captivity to the wild population, showed no difference in survival rates, due in large part to the medical attention and high quality of food they receive, according to the Institute for Marine Mammal Studies.

SeaWorld’s controversial killer whale, Tilikum, died last month from a bacterial lung infection. He was also 35 years old.