More fun in the intertidal

This past Tuesday and Wednesday afternoon I took my marine biology students to the rocky intertidal at Natural Bridges State Beach. We completely lucked out with the weather; the storm system that brought some of the rain that we desperately need had cleared out, leaving calm, clear seas and little wind. Perfect weather for taking students out in the field, in fact.

First of all, we didn’t see any stars. Not that I was looking for them, particularly, but I was keeping an eye out for them and at this time last year I would have seen many Pisaster ochraceus hanging out in the pools and on the rocks. Here are a couple of pictures I took at Natural Bridges in years past:

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The stars, when present, are prominent residents of the mid-intertidal zone, where they feed on mussels. But now, alas, there don’t seem to be any. They WILL come back, and it will be interesting to monitor their population recovery.

I enjoy taking students in the field because many of them have never been there before, and it’s always fun looking at a familiar scene with fresh eyes. When everything is new, it is very easy to be excited and enthusiastic, which these students are.

We saw, among other things:

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Fish! The fish on the right was about 15 cm long. I think it’s a woolly sculpin (Clinocottus analis), but IDing sculpins in the field is pretty tricky.

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This fish was much smaller, only about 10 cm long. It could be a fluffy sculpin (Oligocottus snyderi), or it could be a smaller woolly.

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This is an encrusting sponge, Haliclona sp. I’ve seen it in shades of rosy pink, too. The large holes are oscula, the sponge’s excurrent openings. And that’s a big gooseneck barnacle (Pollicipes polymerus) hanging down from the top of the picture.

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An assortment of intertidal critters sharing space on a rock. How many chitons can you spot?  How many barnacles?  How many limpets?

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This is one of my favorite intertidal animals, the owl limpet (Lottia gigantea). These large limpets are farmers. They keep an area clear of settlers by grazing at high tide. You can see the marks left by this individual’s radula. The limpets also manage their farms, letting the algal film grow on one section while feeding on another.

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I love macro shots like this! The green tufty stuff is Cladophora columbiana, a filamentous green alga. Isn’t it a vibrant green color? To give you an idea of how fine the Cladophora filaments are, that snail in the background is about the size of a quarter.

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And last, a gratuitous anemone shot. Ahhh, Anthopleura xanthogrammica, what a photogenic creature!

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