Suburban Chicago's Brookfield Zoo says a polar bear that was the species' oldest male at an accredited North American zoo has died at age 32.
Zoo officials say Aussie was euthanized Friday after staff determined that "it was the right time" as his health had failed in recent weeks due to degenerative arthritis in his legs and other age-related diseases.
Aussie was born at Adelaide Zoo in Australia in June 1985 and arrived at Brookfield Zoo in December 1986. He and one of the zoo's female polar bears produced five offspring that have since produced nine offspring of their own.
Polar bears are listed as a vulnerable species. Experts say the bears are seeing population losses due to the decline of sea ice and other environmental factors.