Otters act as surrogate moms

The aquarium had not been very successful with returning pups to the wild.
MONTEREY, Calif. -- Toola the otter had no training for the task that fell into her lap. Or snuggled up against her chest.
But for four years she has been a successful surrogate mother at the Monterey Bay Aquarium, the first one in captivity.
In the past, rescued sea otter pups had to be raised by people. And although the aquarium had tried several approaches, it had not been wildly successful in returning pups to the wild, said Andy Johnson, manager for its Sea Otter Research and Conservation Program.
Either the pups didn't survive, or they tended to feel too comfortable around people, particularly any divers and kayakers that happened by. Besides, as adults, released otters pretty much struck out in the reproduction department.
So the idea that sea otters themselves could mother rescued pups had been floating around for a long time, Johnson said.
Along came Toola -- a pregnant adult infected with toxoplasmosis, a neurological disease caused by parasites that has killed many California sea otters in recent years.
She recovered, but the disease left her with a permanent seizure disorder that makes it impossible for her to survive on her own.
The disease also caused her pup to be stillborn. When that happened, "It made us think, 'Wouldn't it be interesting if a pup came in the door?'" Johnson said.
The next day a 2-week-old male pup did just that. He needed a mother to nurse from. Toola needed a pup to nurse.
"So we introduced them," said Karl Mayer, animal-care coordinator for the seal otter program. "... He latched on and started nursing right away."
Except for the first one in the program, all surrogate-raised pups have been raised by hand until they're 6 to 8 weeks old. But the hands that raise them are always wearing latex gloves. And they belong to people wearing big, black capes and welders' helmets to help prevent the pups from getting too familiar with humans.
The youngest pups are fed nothing but formula, which mimics the protein, fat and carbohydrate content of sea otter milk. But it doesn't even come close to mimicking the taste.
Something else isn't quite right about the formula: Caloriewise, of what goes in, almost all comes out. The problem seems to be that the formula doesn't have enough liquid to enable the pup to assimilate it. The solution is to inject fluids under the pups' skin twice a day, until they are about 4 weeks old and start eating solid food such as squid, clams, shrimp and crabs.
The surrogate-mother program at the aquarium focuses on raising individual pups, but it's intended to help save the species, the ultimate goal of the aquarium's sea otter rescue program.

Don't Miss a Story

Sign up for our newsletter to receive daily news directly in your inbox.