From the Associated Press
SEATTLE – Seattle’s Woodland Park Zoo has euthanized its oldest animal — a 47-year-old hippo named Gertie — because of normal, age-related physical decline.

The 5,000-pound hippo has lived at the zoo since 1966. She had osteoarthritis and despite medication, zoo officials say she was having trouble getting around and was in pain.

Two female hippos remain at the zoo’s African Savanna: 31-year-old Water Lily and 10-year-old Guadalupe.

Zoo officials say hippos can live up to 49 years in zoos. Their life expectancy is 45 years in the wild.

Hippopotamuses are listed as a vulnerable species, primarily because humans have excessively hunted them for their meat, fat, ivory teeth and hides.