Dear San Francisco,

Tide pooling

These gooseneck barnacles (Pollicipes polymerus) remind me of zombie claws.  I imagine there being a colony of imprisoned zombie crustaceans inside the rock, trying desperately to escape through the rocky crevice. If you poke them, they slowly move, which only adds to their zombie-esque aesthetic.  These guys form dense colonies in the crevices.  They anchor themselves to rocks with their ovary-containing stalk, then secrete a series of pale plates that form a shell around it’s feather-like legs that comb the water for food. The stalks are edible. Like, no thanks.

This striped shore crab (Pachygrapsus crassipes) wanted nothing to do with me.  I tried telling him he was awesome and that I really liked his striped carapace, but he kept running away.  I took his picture and off he went looking for some diatoms to snack on.  Aren’t his eyes amazing? These guys have excellent sight which adapts well to both day and night, though they are out mostly during daylight hours. 

There were lots of little perforations in the sand teasing me, so I dug and found the source…a blood worm.  They are deposit feeders, which explains the holes…they move along munching on sediments, digesting the organic material between the sand grains.  The variation in color depends on what they’ve ingested.  The darker the sand grains, the darker the worm appears, and vice-versa.

I love sea anemones.  They are so beautiful. When I first came to the West coast, I used to spend hours poking them in tide pools, feeling their tentacles close around me like I was prey.  That’s pretty mean now that I think about it.

This is a green anemone (Amthopleura xanthogrammica). These are members of the phylum Cindaria, which is the same phylum as jellyfish and corals because they have stinging cells. They get their color from pigments and symbiotic zooxantheliae or zoochlorellae living in their tissues.  But, don’t let their pretty looks deceive you. Even though they look like beautiful flowers, they can totally annihilate small fish, mussels, and crabs.  They use their tentacles that are equipped with specialized cells called nematocysts to paralyze prey so they can eat them. Rawr!

Wouldn’t it be funny if we were the UCSD Chitons, instead of the Tritons?  I think so.  I mean, an armored clad mollusk with 8 interlocking shells…I can’t think of a more intimidating mascot..

I digress.

I think this is a California Spiny Chiton (Nuttallina californica).  They feed on Corallina, a type of red algae, and love living in depressions in the rocks.  The sea gulls seem to love eating them.

Yay intertidal zone!

:)