Tilly, the oldest members of the Oregon Zoo’s North American river otter family, died on Wednesday, April 30, heading to the river in the sky.

From 2009 to 2025, Tilly called the Oregon Zoo her home.

“This is a very sad time, especially for Tilly’s care staff,” Jen Osburn Eliot, who oversees the zoo’s North America area, said in a statement. “Some of our keepers were here the day she first arrived in 2009 as a tiny pup. She overcame adversity just to survive, and she helped other otters do the same.”

Tilly hit her sweet 16, deeming her geriatric for her species, according to the zoo. She was euthanized on Wednesday due to declining health. The median life expectancy for river otters is 12.9 years for those living in AZA-accredited zoos and aquariums, an accreditation given by the Association of Zoos and Aquariums.

Her name was donned in honor of the Tillamook River. She was found near Johnson Creek in 2009 at just a few months old, wounded by an animal attack and severely malnourished.

The Oregon Department of Fish and Wildlife facilitated her transfer to the Oregon Zoo.

Tilly didn’t just float on her back all day, she was a mother, known for her “amazing parenting skills,” winning the zoo’s “Mom of the Year” award in 2013. She raised four of her own pups — Mo, Ziggy, Tucker and Nellie — and was an adoptive mom for rescued orphans like Little Pudding and current zoo residents Flora and Hobson.

“Young river otters are extremely dependent on their mothers, and Tilly not only raised her offspring but three other young pups who had lost their moms and needed a second chance,” Osburn Eliot said in a statement.

She was a star online, going viral in 2012 for her NBC sitcom feature in “30 Rock,” which aired a photo of her, noting a resemblance to comedian Tracy Jordan, played by Tracy Morgan.

Tilly’s first pup, Mo, got his own viral moment 12 years ago in a YouTube video that showed his “rough-and-tumble” swimming lessons.

Once threatened by fur trappers, North American river otters are now relatively abundant in healthy river systems of the Pacific Northwest and the lakes and tributaries that feed them, according to the zoo. They are scarce in heavily settled areas, especially if waterways are compromised.

Find a video on Tilly’s story here.