• picture
  • picture
PRI's Environmental News Magazine

Sea Otters: Swimming for a Comeback

Air Date: Week of November 24, 1995

Now numbering 2,300, the sea otter population is beginning to grow slowly though steadily. Rachel Anne Goodman reports from Santa Cruz, California on whether the sea otter will be delisted from the Endangered Species Act anytime soon.

Transcript

CURWOOD: There are few creatures with more charm than the California sea otter. The furry critters have become popular images on calendars and posters. When they almost went extinct in the 1970s, the Federal Government quickly put them on the Endangered Species List. Now the California sea otter population has bounced back, and some scientists who work closely with the marine mammals say it's time to think about taking them off the Endangered Species List. But delisting is not proving to be so easy. Other marine biologists say pollution may be compromising the immune systems of the sea otters, and they are still vulnerable. Rachel Anne Goodman has our report from Santa Cruz, California.

GOODMAN: Each spring and fall, teams of marine biologists armed with maps and high-powered binoculars count the otters from cliffs along the California coast.

(Man: "Well there's 3 otters sitting up there altogether...")

GOODMAN: California's sea otters were nearly hunted to extinction for their fur a century ago. Their numbers plummeted from an estimated 18,000 to about 50 otters. But with the help of the Endangered Species Act, they've begun to bounce back, showing a steady average growth rate of 5 percent a year over the last 15 years.

(Man: "Try to find those mothers and pups back there, see if they're still...")

GOODMAN: I catch up with a census team at the edge of a Brussel sprout field near Santa Cruz. Gray clouds hang over the swells muting the colors, but making for good otter viewing. The team has spotted 3 mothers and pups in this cove.

(Man: "Oh boy, okay, let's see...")

GOODMAN: Recent counts have identified 2,300 animals. That's led a Federal advisory team to talk about the possibility of delisting the southern sea otter in as soon as 5 years. Jim Estes of the National Biological Service is one of the country's leading experts on sea otters.

ESTES: What we recommended was that once the recovery criterion, I've forgotten again the exact number, but somewhere in the mid to high 20, 26, 2700 -- once that number had been reached it would have to be maintained for 3 years in succession. Then the Fish and Wildlife Service could consider delisting the population.

GOODMAN: The team arrived at the delisting number by using computer modeling to calculate how many otters would survive a major oil spill, the threat considered most lethal to the population. Given current growth rates, Jim Estes feels optimistic about the otter's future.

ESTES: We have a growing population, and you know, on a global sense, that's an unusual situation. So I'm heartened by that. I think we're dealing with a species and a population which is doing a lot better than many others. I'd like to see them growing at 15 to 20% a year.

GOODMAN: But not all the signs are good. California sea otters are growing 15% slower than their Alaskan counterparts, and over 50% of all pups die before weaning. Ellen Furrow Daniels is the head scientist at Friends of the Sea Otter. She says it's far too soon to begin talking about taking the otter off the Endangered Species List.

DANIELS: Our concern is that, you know, people are just going to use a head count only as a basis for delisting. And the Fish and Wildlife Service has said they pretty much don't really care if the population is growing at a slower rate than usual. Last spring count we only had a 1% population growth instead of 5. Or if the population is unhealthy for any reason because as long as they see some population growth, they're satisfied that that's sufficient.

GOODMAN: Some of the losses may be due to sharks and human shellfishing activities at the edges of the otter's range. But there may be other problems, too. Rochelle Stadler of the Monterey Bay Aquarium and her colleagues have just captured a mother otter and her pup. On the deck of their research boat they struggle to weigh and tag the unwilling animals.

(An otter screams)

STADLER: Up here we've found a lot of parasites in animals. We're not sure if it's, you know, a trend that they're starting to get more parasites than they had before. It seems like from animals since the 70s, the parasites in the otters have been increasing a little bit.

GOODMAN: A two-year study by the National Wildlife Laboratory found that 40% of the dead otters they examined had died of infectious diseases. In July, scientists were alarmed when 11 carcasses washed up in Monterrey Harbor. Veterinary pathologists still can't find the cause. Ellen Furrow Daniels of Friends of the Sea Otter worries that chemical pollutants may be threatening the otter's immune systems.

DANIELS: The sea otters carry heavy body burdens of environmental contaminants and trace metals and things like that. And to our knowledge, you know, it doesn't cause outright death of the animal, and so everyone just kind of shrugged their shoulders and said well, they carry heavy burdens of these trace metals and pesticides; so what?

GOODMAN: One study showed PCB levels in California otters was 38% higher than in their Alaskan counterparts. DDT levels were 800 times higher. Very low PCB levels have been shown to cause reproductive failure in minks, a related species. But it's uncertain whether researchers will be able to explore some of these questions. The Federal lab which dissects and analyzes sea otter carcasses had its budget cut by 30% as part of Federal downsizing. And Washington politics may be playing a larger role in the fate of the sea otters. Ellen Furrow Daniels says the move to delist the otters may be part of a PR effort to shore up support for the Endangered Species Act.

DANIELS: At the time that we need to be putting greater effort, probably, into getting to the bottom of some of these emerging issues with sea otters, they're being pushed toward delisting, so they can be a success story. I'm not sure the time is right for them to be a success story.

GOODMAN: Even if in 5 years the southern sea otter is removed from the Endangered Species List, the Federal Marine Mammal Protection Act would still provide some of the same protections until the species grew to some 8,000 to 10,000 animals. Researcher Jim Estes feels that whatever their Federal status, the California sea otter will continue to recover.

ESTES: I've never been able to imagine that there would not be some effort being put into conserving and doing research on the sea otter in California, because they -- it seems to be a species that so many people are concerned about.

(Man: "Oh, there's another, a third one. Oh boy, okay, let's see...")

ESTES: The US Fish and Wildlife Service will take up the issue of delisting early next year. For Living on Earth, I'm Rachel Anne Goodman in Santa Cruz, California.

 

 

Living on Earth wants to hear from you!

P.O. Box 990007
Prudential Station
Boston, MA, USA 02199
Telephone: 1-617-287-4121
E-mail: comments@loe.org

Donate to Living on Earth!
Living on Earth is an independent media program and relies entirely on contributions from listeners and institutions supporting public service. Please donate now to preserve an independent environmental voice.

Newsletter
Living on Earth offers a weekly delivery of the show's rundown to your mailbox. Sign up for our newsletter today!

Major funding for Living on Earth is provided by the National Science Foundation.

Committed to healthy food, healthy people, a healthy planet, and healthy business.

Innovating to make the world a better, more sustainable place to live.

Kendeda Fund, furthering the values that contribute to a healthy planet.

The Grantham Foundation for the Protection of the Environment: Committed to protecting and improving the health of the global environment.

Contribute to Living on Earth and receive, as our gift to you, an archival print of one of Mark Seth Lender's extraordinary hummingbird photographs. Follow the link to see Mark's current collection of photographs.