PEORIA, Ill. (WMBD) — The Peoria Zoo announced that its 18-year-old male lion, Arthur, died Thursday.

According to Zoo Director Yvonne Strode, Arthur was humanely euthanized after his quality of life decreased after he was diagnosed with lymphoma earlier this year.

“Earlier this year, Arthur was diagnosed with lymphoma and over the course of the last week, his quality of life had significantly decreased,” Strode stated. “To honor him at the end of his life, the animal care team made the difficult decision to humanely euthanize him.”

Arthur moved to Peoria on Nov. 16, 2008. The median life expectancy of their species is about 16.9 years in managed care.

The lion met his mate, Lizzy, when he moved to the zoo in 2008. They had four cubs that were transferred to other zoos as part of the Species Survival Plan.

The zoo is keeping an eye on Lizzy and keeping her comfortable. Strode said it can be dangerous to introduce adult lions to each other, but the zoo plans to reach out if Lizzy shows signs of wanting a friend.

“Right now what they’re leaning toward is if she is doing okay with the love and affection you give her, might be able to just let her be,” Stode said.

Arthur was cared for by Zoo Keeper Regan Slonecker for the last decade and remembered how he used to play with his weighted ball.

“There is a large weighted ball in the night house and Arthur would repeatedly push it and run away,” Slonecker said. “He would come back to do it again once the ball stopped bouncing around.”  

Peoria Park District Executive Director Emily Cahill said they are encouraging residents to share their favorite memories of Arthur on the Peoria Zoo’s Facebook page. They are also encouraging donations to be made to support lion conservation and animal enrichment here.

According to the IUCN Red List, African lions are vulnerable in the wild.