Wildlife animals have all kinds of problems, but today we're going to discuss a rather surprising one. Today's Moment of Science is about sea otters.

Unfortunately, like many of today's wildlife creatures, sea otters off the coast of California are dying off, and the problem may be felines. A four-year study at the California Department of Fish and Game was recently concluded by wildlife vet Melissa Miller. In this study, Miller tried to find what is at the root of a sea otter sickness that has been causing the number of sea otters to drop dangerously low. She found that sea otters are being infected by toxoplasma gondii.

Toxoplasma gondii is a protozoan that is fatal to otters if it's ingested. They may be consuming it when they eat shellfish, or when they drink sea water. You're probably wondering how this fatal protozoan finds its way into the seas of California. The most likely explanation is housecats. Cats shed live toxoplasma eggs in their scat, which then washes downstream until it reaches the places where otters live.

Not only is this bad news for otters, it also shows us that pollution of the water is going on in ways we hadn't anticipated. If we don't clean up now, there may be more surprises down the road--such as what effect these protozoans might have on humans, since they are harmful to us as well.