Saturday, August 2, 2008

Barking Crab Dock Observations

The area of the dock that we examined was at the very end in a shady section. My picture of a 2 x 2 section of the dock is not very good, and the sealife was definitely not as colorful as my picture seems. However, the orange "stuff" on the dock stuck out and we took a sample of it. Our group found that it was both growing on the dock itself and on mussel shells that were attached to the dock. It had a bright orange color, a jelly like texture, and brainy appearance. The thickness varied throughout the sample as well. I initially thought that it was a type of coral, however someone in class today suggested that it might be a sea squirt. I looked up sea squirts and there was something described in the guide book called Orange Sheath Tunicates. Orange Sheath Tunicates are classified as encrusting animals, and they are typically found growing on rocks or floats.... like a big dock. I don't think that this is exactly what we saw, but it maybe closely related to what we saw. 
We also pulled up a couple of mussel shells, all of which had smaller mussels growing on them. The first mussel was covered in tiny worm-like animals. Im guessing that they were shrimp of some kind, but they were extremely small and I havent found anything in the guide books that accurately describes them. These animals had large head sections with long antennae and what looked like bristly sets of legs. They had 2 thicker legs toward their middle section that seemed to be largely responsible for their movement, and their hind sections were hook-like and curled in when the animal moved. Their markings were very distinct as well; they were a translucent yellow color overall with brown striping down their bodies. Im wondering if it's possible that they were younger shrimp that weren't yet fully developed. My best guess so far is the opossum shrimp. They live among seaweeds (which there was plenty of on the dock) and are translucent with dark brownish spots. They have plenty of bristly like appendages. However, it says in the guide book that their tale-pieces are forked, making a fan. Our samples hind sections did not look this way, but as I said they could have been young shrimp that weren't yet fully developed.
There were many other types of worm-like animals on the mussels, equally as hard to identify. One of the mussels had anemones on it; we identified them as frilled anemones. They were translucent/whitish with lots of very thin white tentacles. There was also a lot of dark brown sea weed that was very grassy, and every now and again there was a piece of bright green sea-weed that looked lettuce like. 

....for some reason my pictures won't load. Ill try again later or ill send them to bruce. 

No comments: