While doing a recent beach survey, I noticed this Feather Boa Kelp (Egregia menziesii) washed ashore:
It looked quite young — relatively short overall length, with broad blades, and a small holdfast.
When I looked more closely, I was intrigued by the holdfast:
Can you see that the holdfast is attached to a small pieced of wood?
It might be easier to see this from below:
I wondered about the history of this kelp. Did it start growing on a piece of wood that was lodged in rocks somewhere and then part of the wood broke off and washed ashore? Or is it possible the kelp started growing on a small piece of floating driftwood? Have you noticed Feather Boa Kelp growing on wood before?
P.S. I laughed when I read the description of juvenile Feather Boa Kelp on the California Seaweeds eFlora website. It says they look like lasagna noodles. A fun description of those broad, ripply blades!
Not much time tonight, but I think you can see why I couldn't resist sharing this photo. It's one of my favorites of the year!
If you've been following this blog for a while, you might have seen this species before, but it's been several years. This is Manania gwilliami, a beautiful staurozoan. [Staurozoans are now a separate taxonomic class within the cnidarians. Sometimes they're informally called stalked jellyfish.] It was found locally today in the rocky intertidal zone. We didn't measure it, but estimate it was ~12 mm long.
Here's the entire animal:
This individual had beautiful purple highlights. Check out this close-up of two tentacle clusters:
When looking at the tentacles, I noticed some whitish pads at the base of some of the tentacles. Here's one view:
After doing some research, I learned that these are adhesive pads. It is hypothesized that when the staurozoan releases its pedal disc (the base of the stalk) from the substrate, it sometimes holds on with these pads while it reattaches. Since I haven't been able to find many pictures of these interesting structures, here's one more image. Look for the swollen white areas at the bases of the front three tentacles:
I'm sharing these staurozoan photos with you thanks to Hao Hao, one of Eric's summer students at the marine lab. Her curious eyes spotted it attached to a blade of algae in the intertidal zone. Thanks, Hao Hao!