Saturday, August 1, 2009

Assignment: What the Hell is That?

Today was the first day of this exciting course and we were able to observe many different species that call the inner Boston Harbor home. Though we made many observations of barnacles, rockweed, kelp, mussels, and seashells, it was when we broke into teams down at the Barking Crab when we found more intricate species. I worked with Sam today and we were both able to spot some interesting organisms on the under-side of the docks. We started out in the shaded region and found some clumps of blackish-brown mussels, some dead some alive. Along with the mussels, there were small pieces of green, leaf-like plants attached; we came to the conclusion that it was sea lettuce. Also in the heap of mussels and sea lettuce, came little sea creatures that looked like a part of the shrimp family. It turned out that they were indeed, and we concluded that they were either water fleas or fish lice as they had around six to eight limbs and a curved vertebrate that resembled a shrimp. The last interesting thing we saw in the shaded area was a "fuzzy mushroom" looking species which turned out to be frilled anemone.

From the shaded region we moved to a more sun-filled area to see if the inhabitants were different. Along the way, one of our classmates spotted a red starfish which was pretty exciting, although we couldn't actually get a hold of it. Once Sam and I leaned over the dock we found it to be quite different. Though the sunny side did have green sea lettuce and a couple of frilled anemone, we found a couple of more interesting things as well. There was definitely more color as we saw some red sea lettuce and a really weird gray-brown piece attached. When we pulled it out we saw an interesting star pattern on it that Sam said looked like an "old woman would wear." We thought it was some sort of tube sponge but after looking at the Hitchhikers Guide, it is certainly a star tunicate. It had the exact pattern and color. We were able to conclude that the although the sunny side and shaded side have similarities, they are also different. As for the orange, "cheeto" looking tubes; after looking into the field guide, it is fair to say that it is a finger sponge. A finger sponge can be red-orange in color, branched in a v-like structure, and pores that are reminiscent of eyes.

As for the differences between the species found under the dock this year versus last, there seem to be some similarities and other things that are missing. As we discussed at the end of class, we have had more rain this year which brings in changes to the water such as: clarity, salt amount, bacteria levels, and current strength. The differences I see from the picture of last year to what I saw today is that there seems to be more of the orange substance called finger sponge, more mussels, and quite a bit more sea lettuce. As a whole, the picture from last year looks like it has more abundance of the species we saw. I think one could say that the rain causes a stronger current which doesn't allow for some of the species to settle so easily and grab to the side of the dock, therefore our rainy season has shown that there is far less abundance on the docks from last year where the rain was not as prevalent.

Chris Connolly.

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