California Sea Hare Slugs

California Sea Hare Slug Life

Imagine getting a school assignment to create a creepy and crazy animal. The California sea hare slug would be a great result! It's almost as big as a football, weighing up to five pounds. It's wobbly and sticky when it emerges out of the ocean and gets stuck on land. Ready to spew cloudy red ink when disturbed, in the water it sticks out frilly "fins" to propel itself around. And finally in an animal mix-up, it has two rabbit "ears" on the top of the front of its body, giving it the name sea hare. These are not ears at all, but tentacles that helps the slug to move. The slug also has front tentacles that help it to smell (so imagine a nose on tentacles, another crazy feature.)

Here in California, sea hare slugs are conducting an invasion. Many have been flinging up on beaches, jetties, and rocky shores. Scientists believe warmer water temperatures may be causing them to come ashore. They might prefer to stay in the water, but they can sustain some time on land by losing up to one-third of their body weight.

They become such large mollusks by eating a vegetarian diet of kelp, eelgrass, and algae. They find this garden on the edge, shallow waters where they can get caught by low tides.

California Sea Hare Slug Quest

With warmer ocean temperatures, even people who don't want to see sea slugs have come across them on sandy and rocky shores. We were able to find four gastropods on a jetty in Alameda. Due to their large size and glistening ability to catch the light, they were easy for us to spot during low tide.

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