A Feline Disease Threatens California's Kelp Keepers
CK:
Well, we know that the otter population has a lot of disease. It's not
a healthy population and there are a lot of concerns as far as their recovery.
The question is, can we do anything about it? I mean, I don't think you
can ask people to get rid of their cats. We know the parasite in cats
is a major problem in the AIDS population, but people still keep their
cats.
CD: What about throwing away cat litter instead of flushing it down the toilet.
CK: If we knew that was a cause, yes, we'd recommend that. But we don’t know if that's a cause.
CD: One problem also has got to be pressure because there are so many people in this area now. Especially where things like runoff are concerned. You take out the wetlands, you make concrete channels out of creeks, you pave everything, and a lot more nasty stuff ends up in the ocean.
CK: Definitely. Ideally, we'd like to be able to show how the things we put in the water affect otters. We want to look at contaminants like oil, and see if they're linked to changes in the otter immune systems. This might make them more susceptible to disease.
If you think about it, it's pretty easy to understand that if a small colony has been struggling to recover over the last 100 years, then in this new, totally different environment, they're going to have problems. There were so many otters before (editor's note, some estimates go over 300,000 otters before hunting decimated them). If one died because it couldn't’t adapt to changes, then there was another to take it's place. Today, those numbers aren't there.
CD:
It's interesting to see all these surfers out here, and that little group
of otters offshore. The water here is so glassy because of the kelp. But
don't otters have a lot to do with that kelp?
CK: Otters are key because they're the reason that the kelp forests are out there. Without otters, urchins dine on the kelp and it's gone. And the kelp just supports hundreds of species. They call an area that's had its kelp taken out by urchins a barren. An urchin barren.
CD: It must be somewhat disheartening for the people working on this research to find so many sick otters.
CK: Well, we thought for awhile that things were going great and that we would one day be able to take otters off the endangered species list. If this level of disease persists, it's hard to see how the otter population can recover.
External Otter Links:
Friends of the Sea Otter
Monterey Bay Aquarium's Live Otter Cam
A Fascinating Article on the Rediscovery of Otters in 1938
More Otter Info from the Monterey Bay Aquarium
Outdoor Cats Blamed in Otter Deaths -- New York Times
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READER COMMENTS
Tue Jan27, 2009, 9:49 AM
What they are not telling you is that over 20% of people are infected with brain-worms (that's what Toxoplasmosis is called); cat feces dumped into sewage remain infective even in the Ocean for a year; and when a surfer ingests seawater (or an otter eats a clam) containing the oocytes (eggs) the brain-worms hatch, migrate through the walls of the intestine, and infest the brain, muscles and eyes. The immune system usually contains them, so they "encyst" and can remain dormant for the rest of the infested person's life. But they do have effects on behaviour; for example, mice infested with brain-worms tend to lose their fear of cats, making them easier to catch and also re-infesting the cat. Cats are the only species in which the brain-worms are excreted in oocyte form; in the encysted form, you can get it from eating uncooked meat. Since all sewage discharges come back to shore (if you don't believe this, imagine if they put dye in the sewage), every swimmer is at risk.