Tilly, a river otter, came to the Oregon Zoo in 2009 as an injured and orphaned pup. She birthed four pups while at the zoo.

A zoo euthanized a “beloved” North American river otter after her health declined due to her age, Oregon zookeepers said.

This is a very sad time, especially for Tilly’s care staff,” said Jen Osburn Eliot with the Oregon Zoo, in a statement.

Although they used to be threatened by hunters wanting their fur, river otters are now living in the Pacific Northwest and in lakes where they feed, officials said. “This is a very sad time ...