By CBSLA Staff

LOS ANGELES (CBSLA) — Two of the Los Angeles Zoo’s lions, Hubert and Kalisa, were euthanized Thursday due to declining health and age-related illnesses, zoo officials said.

(credit: Jamie Pham/Los Angeles Zoo)

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The decision to euthanize the 21-year-old companions was a difficult one, the Los Angeles Zoo said.

“This is a very hard loss for our Zoo community,” the zoo’s curator of Alisa Behar said in a statement.

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Hubert was born Feb. 7, 1999 at the Lincoln Park Zoo in Chicago and fathered 10 cubs over his lifetime. He met his long-time companion, Kalisa, a female African lion born Dec. 26, 1998, at the Woodland Park Zoo. The pair moved from the Woodland Park Zoo to the L.A. Zoo in 2014.

“You cannot think of Hubert without thinking of his companion, Kalisa; they’ve been an inseparable couple for years,” Behar said.

Zoo officials say that even though the pair have been together since 1998, they never produced cubs together.

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The average life expectancy for African lions in the wild is mid-teens, and about 17 years in zoos, according to LA Zoo officials. African lions are native to the savannas, arid woodlands, and semi-desert regions from south of the Sahara Desert to South Africa.