Staff at California's Monterey Bay Aquarium are mourning the most remarkable sea otter they have ever encountered. Toola, who died at age 15, was the first captive sea otter ever to serve as a surrogate mother to others, raising a total of 13 pups, some of which now lead their own packs in the wild. She was rescued in 2001 and became mother to an orphaned pup weeks afterward, the San Francisco Chronicle reports. She suffered a brain infection that required twice-daily medication and prevented her release back into the wild.
Before Toola raised her first pup, rescued sea otter pups never learned the skills that would let them survive in the wild. "Toola was without question the most important animal in the history of our program,” says the manager of the aquarium's sea otter conservation program. “She showed us that captive otters could successfully raise orphaned pups for return to the wild. She inspired a critical piece of legislation that is helping protect sea otters. And she inspired millions of visitors to care more about sea otters." She seemed to be failing last week, but appeared to bounce back after treatment. She was found dead the following day. "She went out her way on her terms, and I believe died with dignity," said the otter program manager. (Read more sea otter stories.)