US zoo euthanizes hippo believed to be about 59

A Nile hippopotamus believed to be the oldest in North America has died at an Ohio zoo.
The Cleveland Metroparks Zoo says the male hippo was euthanized Monday due to "advanced age-related ailments." The zoo says the hippo was named Blackie and was about 59 years old.
A zoo announcement says Blackie sired three male offspring after arriving at the zoo from Africa in 1955. Blackie was born in a game sanctuary in Tanzania.
The zoo says hippos typically live 30 to 40 years in the wild and can live longer in captivity.