Nile, a male lion who died on Jan. 31, 2020 at age 25 years and 10 months, is seen at the Kyoto City Zoo in Kyoto's Sakyo Ward in December 2019. (Mainichi/Yoko Minami)

KYOTO -- Nile, Japan's oldest lion, died aged 25 years and 10 months at the Kyoto City Zoo in this western Japan city's Sakyo Ward on the morning of Jan. 31.

Nile, a male, was born on March 9, 1994 at the Adventure World theme park in the Wakayama Prefecture town of Shirahama, and moved to Kyoto in July 1997.

Lions' average lifespan is thought to be 10 years in the wild and 20 years when raised in captivity. Nile's nearly 26 years were equivalent to over 100 in human terms.

According to the zoo, Nile began to leave leftover food on Jan. 10 and had not eaten at all since Jan. 27. He stood up and walked on the morning of Jan. 29 but became unable to rise that evening. Zookeepers gave him a painkiller on the morning of Jan. 30, and administered fluid replacement and medicines in the afternoon. Nile was found dead at 8:05 a.m. on Jan. 31.

The previously longest-lived lion in Japan was a male named Leo. His exact date of birth was unknown, but he lived in captivity for 24 years and six months, and passed away in 2013 at the Tokuyama Zoo in the Yamaguchi Prefecture city of Shunan.

A visitor who earlier saw Nile wasting away suggested that the zoo should consider euthanizing the elderly lion. However, zookeepers continued to care for the big cat in the hope that he would pass away with dignity.

(Japanese original by Yoko Minami and Kanae Soejima, Kyoto Bureau)