Tuesday, July 23, 2013

Dock Specimen Observations

Today was our very first hands on experience on the Harbor. From early in the morning, I was continuously learning. Our first stop was on the north end of the Long Wharf right in front of Christopher Columbus Park. This observation occurred on July 14th, which meant that it was summer. It was 9:55 am local time during low tide. It was 90 degrees Fahrenheit with a light variable wind. The water quality was clear with 3-5 ft of visibility. This area consisted of a rocky sea wall with a 'beach' that consisted of pebbles, cobbles, and a sand mixture. There was vegetation that seemed to resemble seaweed. The vegetation colors varied from green to a dark brown or even purple coloring. As a group, we discussed it's possibility of the vegetation being classified as rockweed. We also observed vegetation that resembled bright greed seaweed. On the rocky sea wall, one could observe a mossy-textured vegetation in the intertidal zone that most closely resembled green algae. The nearby area is intensely used by people, which was obvious by just looking at the water. The water showed several bottles and other forms of garbage, as well as a trash can that seems to have been tossed into the water. Within the sub-tidal zone, a different world was shown. The only vegetation visible from our perspective was the purple and green seaweed. Several crab-like creatures and small fish were visible in this area. Below are some pictures that help give a clearer idea to our surroundings.

The picture above shows the rocky sea wall with the intertidal zone, sub-tidal zone and its surroundings that have been described above.
The picture above shows the sub-tidal zone and the Benthic Layer and its surroundings that have been described above.
After observing the aforementioned area, we walked about 15 feet to another location. This location contained ramps and docks for transportation and recreational boats used consistently throughout any given day at the Long Wharf. This given observation was made on July 15th 2013 at about 10:35 am, standard eastern time. At this time, there was a low tide and the temperature was about 90 degrees Fahrenheit. There was a light variable wind and the water clarity was cloudier than the previous observation. The water had about a 6 inch visibility at the time of observation. The observable area consisted of an intertidal zone with several rocks and a rocky sea wall. Again, there was visible vegetation including green algae and varied colors of seaweed and rockweed. Because of the water clarity, the only observable creature in the water seemed to be a crab. Below are some pictures that help illustrate the observed area.

The picture above shows the intertidal zone, sub-tidal zone, and the Benthic Layer and its surroundings that have been described above.
A short walk after observing the above area (about 15 feet), we observed an area that closely resembled a 'beach.' Similar vegetation was in this area, but no other organisms were visible other than the vegetation and birds.

The picture above shows the intertidal zone, sub-tidal zone, and the Benthic Layer and its surroundings that have been described above.
After observing these areas, we walked for about half an hour onto a small dock. In this dock, we would observe organisms more closely. On this dock, it was evident that the tide was still low by observing the pillars that held the boardwalk and its vegetation was similar to the intertidal zones we had seen earlier that day. From the docks, sea stars, mussels, and other organisms were visible. In our last location, we observe organisms from under a dock more in depth. Below are some pictures that were taken on our first dock stop.

After walking and discussing several topics throughout the day, we reached our final destination of the day; the Barking Crab dock. On this dock, we split up into our teams and observed some organisms that were attached to the docks. Our first specimen was sea lettuce. This sea lettuce was very bright but contained other animals with it. From looking in our field guide, we discovered that these creatures might be a Sea Pill Bug. These creatures were on most of the vegetation that we took from the docks and seemed to stop moving after about a minute of being taken out of the water. Below are some pictures of the sea lettuce and sea pill bugs.

After observing and attempting to name the organism above, we pulled out another specimen from the dock. This specimen was apparently a blue mussel with two barnacles attached to it. After close observation, our team decided that we believed the barnacle to be a bay barnacle. Below is a picture of the specimen.
As you can see from the picture above, there seems to be a coating on the other end of the mussel. As a team, we decided to remove the covering to better examine it. After careful examination, we decided that this covering most closely resembled a golden star tunicate. Below are pictures that show this golden star tunicate.
Our next specimen had several parts to it. We removed a grass-like vegetation with several bugs in them. This also contained parts of the 'covering' that was found on the mussel. The grass-like vegetation was a reddish purple-ish color. After its close inspection, we determined that it was brushy red weed. The bugs were similar to the ones found on the green sea lettuce, which were sea pill bugs. The coverings were determined to be the golden star tunicate from the blue mussel and orange sheath. Another vegetation that was found seemed similar to the green sea lettuce, other than its color. It was identical to the green sea lettuce except that it was purple to a red color. However, after a closer look, we found that it was intertwined with green sea lettuce. Because of these factors, we determined that it was in fact red sea lettuce. By the end of our observations, we noticed a small shell on the deck. It was white with some stains on the outer covering. It reminded me of the shells found on the beaches of the Jersey shore. We decided that this shell most closely resembled Morton's egg cockle. While our observations were taking place, we noticed something floating on the water. After removing it from the water we inspected it carefully and found that this vegetation was different from what we had seen throughout our experience on the dock. This green weed-like vegetation seemed to be tangled and had some air-filled pockets on the ends. After looking at our field guide, we decided that it looked more similarly to ascophyllum mackaii. As a form of a disclaimer, I must add that our distinctions between the names of these specimen may be incorrect or a misnomer. As a team, none of us had any professional experience in labeling organisms from simply looking at a field guide. We may have misnamed a species or confused it with an invasive species that was not listed in our book. Other than that, we have tried our very best in observing and labeling the specimen from under the dock. Below are some pictures that we took of the specimen from the dock.
From left to right: green sea lettuce, brushy red weed, orange sheath, golden star tunicate

From left to right: green sea lettuce and orange sheath

Red sea lettuce attached to green sea lettuce

A piece of the ascophyllum mackaii

A larger look at the ascophyllum mackaii with green sea lettuce on the bottom

A look at the inside of Morton's egg cockle

A look at the top part of Morton's egg cockle

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