After being classified as threatened in 1977, California sea otters—those furry, whiskered aquatic acrobats—began a slow, steady comeback. But now biologists fear their numbers may be falling. Michelle Staedler, Monterey Bay Aquarium’s sea otter research coordinator, is determined to find out what’s bringing the otters down.
Q Right now, how many sea otters are there in California?
A Last spring, 2,692. That’s 1.6 percent fewer than in spring 2005. Averaged over three years, the population is holding—but it should be growing.
Q Is there a target?
A There were perhaps 20,000 before the otters were hunted almost to extinction in the 19th century. It’s reasonable to think there should be 15,000 now.
Q What’s hurting them?
A Food limitation and disease. Detailed necropsies in dead otters began in 1995. Forty percent were dying of disease.
Q Such as?
A Otters are prey to a parasitic worm carried by birds that burrows into their guts. They’re also dying of toxoplasmosis and other diseases that kill brain tissue, causing seizures and disability.
Q What can help?
A Toxoplasmosis is caused by a parasite in cat poop. It’s possible that feral cat and mountain lion scat is washed to the ocean by runoff, but people flushing cat litter are also likely sending parasites into otters’ habitat. Always put cat litter in the trash, where it can break down before it gets into the water.
Q Where can we go to watch otters?
A All along the Monterey Peninsula. Spy them through scopes at the back of the aquarium.
Photography by Sean Arbabi 
This article was first published in March 2007. Some facts may have aged gracelessly. Please call ahead to verify information.