(Fox News) – The Louisville Zoo in Louisville, Kentucky,
announced it made the tough decision to euthanize Helen
on Friday, Oct. 14,  because her quality of life declined for
several months due to natural aging.

The zoo said Helen had been in "remarkably good health
for most of her life" despite being diagnosed with "expected
age-related arthritis and some periodontal disease.”

According to the media release, In recent months, Helen
developed instability and tremors that put her at fall risk
and impacted her day-to-day life. 

Female zoo gorillas typically have a median life expectancy
of about 39 years.

Helen’s estimated birth year is 1958, and she was born in the
wilderness of Western Africa, which is now modern-day
Cameroon.