BUFFALO, N.Y. (WIVB) — Roughly one month before her 30th birthday, the Buffalo Zoo says its oldest North American bison has died.

Wilma was humanely euthanized following the recent decline of her health, the zoo says. Not only was Wilma the oldest American bison at the Buffalo Zoo, but she was also one of the oldest known bison to live in a North American zoo, in general.

She lived much longer than a bison is expected to, which the zoo says averages out at 15 to 20 years.

Born June 2, 1993, Wilma “lived at the Buffalo Zoo her whole life,” the zoo says. A mother, Wilma had two male offspring, in 1998 and 1999.

“Her caretakers will remember Wilma for being gentle and a great animal to work with. She loved apples, rolling around in fresh piles of sand, and giving kisses to her keepers. She had always been the head bison in the herd and did a wonderful job of showing the Zoo’s new young bison the ropes. Wilma will be greatly missed by all of us here at the Buffalo Zoo.”

See photos of Wilma here.