Thelma, Oregon Zoo's mother otter, is euthanized
Thelma, the Oregon Zoo's aging sea otter, was humanely euthanized Saturday when her health began to decline.
Zoo officials said Monday that Thelma was about 19 years old and had survived into old age with one lung.
Thelma was rescued as a pup in 1998 by the Monterey Bay Aquarium's Sea Otter Research and Conservation program. She came to Portland in 2000 with her companion Eddie, when the zoo opened its Steller Cove marine life habitat.
"We knew she was getting up there in years and wouldn't live forever, but it's still hard to believe she's gone," said Nicole Nicassio-Hiskey, the zoo's senior marine life keeper, who worked with Thelma for more than 15 years. "She beat the odds at every turn. She was incredibly tough, but at the same time she had a really gentle and nurturing spirit."
On Jan. 5, 2001, despite birth-control implants (zoos are prohibited from breeding sea otters) and the fact that she was still young, Thelma gave birth to a pup named Ozzie, the first southern sea otter to be conceived, born and raised by an otter in human care. Ozzie lives at the Georgia Aquarium in Atlanta.
In 2006, zoo veterinarians removed one of Thelma's lungs that had been damaged and could not be repaired. "Remarkably, Thelma not only survived but thrived," Nicassio-Hiskey said.
Thelma was named the zoo's Mother of the Year in 2015 for adopting orphaned otter pup Juno, who'd been rescued along the California coast in 2014.
Sea otters are listed as threatened on the Endangered Species list. Oil spills, fishing nets and diseases have taken their toll on the species, reducing its numbers by about 50 percent during the past 30 years.