In a short walk, I collected a bag of treats for my hermit crabs, with only one sample of each species, I ended up with a full grocery bag. Sea lettuce, of course. Two kinds of rockweed. Turkish washcloth, and a black, leathery, pimpled towel seaweed, four or five kinds of kelp, the invasive sargassum, several tiny blackish curly weeds, Pacific rose algae, red blades, rubbery threads, ... I didn't bother with eelgrass; the aquarium is planted with a fair crop from my last collecting trip.
I collected three pieces of a red algae that was coated with bryozoans. None of the algae were entire; they were stalked, and opened out into red blades, badly torn, rotting along the edges; I couldn't determine their shape or full size. But the bryozoans intrigued me.
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| At home, in a bowl. The stalks are encrusted with these hard blobs. The pink stub at the right seems to be a growing tip of the algae; there were several of these. |
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| One of the blobs. Each little hole was the home of one zooid. If you look really closely (click for full size) you can see tiny pink pores on the body of each case. |
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| Where the stalks met the blades, the structure changed; here they lie flat, one critter deep. Membranipora sp., maybe? |
I don't think any were alive; they'd been lying out on the shore for a while. I looked while they were underwater, but saw no hint of movement.
I've been searching for an ID in my books and on the web, but can't find any that take these two forms on red algae. Blobs on rocks, yes. Single layers encrusting kelp, yes. Both together, no.
Membranipora membranacea is common on bull kelp on our shores; it makes circular, flat colonies on the blades. I could find no photos or record of it making these blobs.
And the crabs, hermit and "true" are happy, busy climbing and feasting.
Always learning, always investigating the life on our shores, always posting your findings. Thanks for sharing your journey, Susannah.
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