Saturday, July 31, 2010

Excursion 2

(above is my fantastic drawing of a green crab....dont act like you're not impressed....)

On our never-ending quest for knowledge about Boston's harbor, today we observed several sites and even got our hands dirty (figuratively) with specimens living near the Barking Crab. First, we observed the water clarity off the dock near the aquarium, which we ranked, on average, to be roughly a 6 out of 10 (10 being the clearest possible water). This was encouraging! Additionally, we observed the physical characteristics of specimens living within the intertidal zone, such as some brown/ black seaweedish looking characters, as well as green, mossy looking creatures just above it on the seawall. Shortly after, we observed another rock wall only a few hundred yards away. This one, however, was distinctly different because it lacked the mosses present at the previous site. We concluded that the seaweed/mosses were not present at this site because neighboring condominiums blocked out the majority of the sunlight. In the absence of sunlight, such autotrophic specimens cannot live, which explains why they were not there.
Moving on, we ran into a nice fellow from NOAA who explained the significance of his tide-measuring apparatus. He claimed that any more than a 6 millimeter discrepancy would result in him having to re-calibrate the apparatus, to ensure correct readings. But more importantly, to ensure that the ocean water levels are not rising or falling.
Finally, we reached the Barking Crab. Though some students had difficulty navigating their way through the dangerous bridge..... we all made it down to the docks in one piece. There, we scooped, cut, snagged and captured various aquatic life forms living within the Barking Crab dock community. The dock was teaming with various specimens!!! Fish, algae, crabs, name it, the Barking Crab dock has it. After documenting our findings, we released our temporary captives back into the wild and headed out for beer and lobster rolls. I mean, aaahhhem, just lobster rolls.
After searching several online sources for information about the specimens we saw, i stumbled upon the New England Aquarium site.... This was an extremely useful resource, as it explained in great detail what kinds of organisms are typically found within Boston Harbor, how to identify them, and supplemented the info with a picture of each specimen.
the following is a list of specimens we encountered (or at least i think we encountered) while on the dock:
1. Northern Rock Barnacle- these were first observed on the rock walls close to the aquarium, but are very common in Boston harbor. We saw many, many barnacles whose color and shape resemeble that of the ones on the New England Aquarium website
2. Sea Lettuce- this "lettucey" looking organism is aptly named. because it looks like lettuce. we found this under the docks. Well depicted by the website, pretty easy to identify.
3. Green Crab- i believe group 2 found this little guy swimming around the docks. There color and shape helped us to distinguish them from the rock crab.
4. Rock Crab- my group (group 3) found an immature rock crab, or so we think we found...
5. Blue Mussel- very common, i believe everyone had a chance to observe closely this organism.
6. Bubblegum Algae- this i looked up, and is commonly located on blue mussels. now that i'm thinking about it, i believe we saw this also
7. Brown kelp- floating nearby one of the docked boats
8. Right coiled tubeworm- typically located on rockweed (which we also observed) and characteristically curls itself up in a tube-like fashion if it feels threatened
9. Golden Star Tunicate- the cute little flower-looking organisms growing on the mussels. Clearly stated on the NEAQ website that they commonly grow on mussels, and often have an orange or pink color. they did!
10. Atlantic Silverside- although professor Berman did not confirm or deny that the baitfish we caught was in fact an Atlantic Silverside, the physical characteristics we observed were similar to that described on the website
11. Longhorn Skeleton Shrimp- the mostly translucent shrimp we found rumaging through the seaweed.
12. Rockweed- professor Berman divulged early on, accidently, that this was the name of the organism we found on the rockwall early on in the trip. The NEAQ site confirmed the slip-up. The organism was in fact a rockweed. Thanks for the free-bee, professor.

-matt heim

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