BROOKFIELD, Ill. (AP) — A 50-year-old gorilla that was one of the oldest gorillas in a North American zoo has died.

The Chicago Zoological Society says Ramar, a western lowland gorilla living at the Brookfield Zoo, was euthanized on Thursday after a series of chronic, age-related health problems.

Ramar was brought to the U.S. in 1969 after he was orphaned in the wild and raised by a human family until he was about 6 years old. He spent time in zoos in Philadelphia, Miami and North Carolina before arriving at Brookfield Zoo in 1998.

Zoo officials say Ramar was the sixth-oldest western lowland gorilla in a North American accredited zoo population. The median life expectancy for the animals is 32.

Ramar, who was the oldest animal at Brookfield Zoo, sired three offspring.