Saturday, July 31, 2010


Today we walked from Long Wharf to the Barking Crab, stopping to observe the built shoreline along the way. We noticed many things, including various plant life in the and barnacles in the intertidal zone. At the Barking Crab, we found many different organisms. The creatures I describe below all come from the side and bottom of one of the finger docks outside the restaurant (fouling organisms). My group (group 2) took the temperature of the water (twice) and found that it was about 71 degrees 3 feet from the bottom. We also estimated that the water was about 18 feet and 7 inches deep. Among the organisms that we found, there were both plants and animals.


One plant that I found was brownish-greenish with many branches that ended in bulbs that burst. It was very common and covered the sides of the docks as well as the sides of the walls along the shoreline. The bulbs seemed slightly lighter than the rest of the plant. Online, I found that there are three types of brown algae that form the primary intertidal zone of northern New England. Out of the three kinds, only two had “bladders” or bulbs that burst. One sounded much more similar to what I saw today, with more bulbs and a more branchy structure. This was the Bladder wrack (fucus vesculosis). I found the description at this website: 

Another plant that group 2 encountered was a slightly wavy, bright green, thin sheet that wrinkled when dried. I determined from the website above that this plant was sea lettuce (Ulva lactuca) . It is found in northern New England near the low tide mark. It is one cell thick. 


The crab we found was about 1 inch across, and light greenish-brown in color with a clearer underside. There were small dark spots on the top as well. We were also informed by professor Berman that it was female, because it had a triangle shape on its underside. The most distinctive feature of this crab is that it only had three teeth. All the crabs in the field guide that looked similar to this crab has more teeth. However, after looking at the Hitchhiker’s guide I saw that the Asian shore crab  now extends from Maine to North Carolina and likes the intertidal and subtidal zone. Most importantly, it only has three teeth! The crab in the guide looks like a more red-orange color, but it says that it varies in color so I think it is still likely that this is the crab we found. It fits in size too! The guide says they are usually about 1 inch across.

Another animal that we found, along with many other groups, was a stick-like, shrimp-like creature. I drew a picture of it, shown below along with a photo. It was very thin and looked like a stick, with one main joint and a few smaller branches coming off the end. It was pinkish in color. I was about an inch long. Looking at the various types of  shrimp in the field guide, I determined that it is most  likely a long horn skeleton shrimp. Its small for the description, which says its usually 2 inches long, but the coloring is correct, it has a large second appendage.


Another group found the "orange daisy" creature covering a mussel shell. After looking at the photograph, I believe that this growth is a Golden star tunicate: I looked at tunicates in my field guide and found that the orange daisy flowers looked like the golden star tunicate in my book, except that they were white. I read the description and found that they can be a variety of colors, including orange, and they are found on the east coast.

A common finding that we had were mussels. In reality, most mussels we found were actually empty shells, but we did find some that were alive. Many had growth on them, such as the golden star tunicates or barnacles. The ones we saw were about 3 to 5 inches tall and 3 inches wide. However, below that they ranged from light almost purple blue to an almost black color. Looking in the field guide I determined that these were blue mussels, which are about 4 inches high and 2 inches long.

Another interesting thing that my group found was what seemd like squishy balls. They were dark greenish-grayish  in color and jelly-like. We opened one by cutting it and inside found a clear, mucous-y substance surrounding what looked like a light gray spiral with a dark black inside.I also drew this and it is shown above. I would say that they ranged

from .5-2 inches in diameter. It seems likely that it could be a sea grape (molgula manhattensis). They are grayish green in color, live on pilings, and ranges from Maine to Texas, and about 1.5 inches in diameter.



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