Monday, July 16, 2012

Seaweed, striped bass, crab cakes, oh my!

Long-Horn Skeleton Shrimp: These guys were by far the creepiest and most common thing I encountered under the dock. Their long spindly bodies seemed to find their way onto every piece of seaweed, empty mussel shell, and stationary submerged object. When picked up out of the water, these shrimp would lash out their tail section, revealing their long red tinted form and "grasping appendages." (National Audubon society Field Guide to North American Seashoe Creatures, Meinkoth) I was able to match pictures I took to pictures in my guide book, which also stated that these creatures can be found "on seaweeds, hydroids, and sponges from the low tide to water line" along the Atlantic Coast. (Meinkoth)

Orange Sheath Turnicate: The mysterious orange things! I found this colony of orange clusters at the first dock we visited. The smaller clusters were less than an inch long while some of the bigger ones I spotted appeared to be about 5 inches long. They were attached to the underside of the docks mixed in with the sea lettuce.

(Golden) Star Turnicate: This black and white colony of ovular organisms was found in the brackish water near the dock by the Barking Crab. The defining characteristic that helped me determine this was a Star Tunicate was the white star like pattern at the center of the black jelly-like spheres, which matched up with the finding in my field guide. The description of this animal stated that they are found in brackish water, attached to pilings, seaweed, and other solid surfaces. This animal did not move on its own when removed from the water and after a few minutes began to perish from being out of the water, shrinking from its original form.

Sea Lettuce: The long, translucent, wavy leafy green that appeared similar to real lettuce is called sea lettuce. This plant can be found free floating in the water or attached to rocks and docks. Although I could not find this plant in my field guide, according to the Rhode Island Habitat Rehabilitation, "sea lettuce is often found in areas of exposed rocks and in stagnant tide pools" and "grows in both high and low intertidal zones." This source also explained that a large presence of sea lettuce is an indicator of nutrient saturated water since this plant thrives on sewage runoff and pollutants.

Rockweed: Rockweed was scattered throughout the pier and wharf structures we visited today, attached to rocks and walls that were stationary but not completely submerged under water. This seaweed was brown at the base and had clusters of 5-8 stems that branched off into lighter greenish yellow air pockets. These pockets allowed the plant to float at the surface and adjust its position with the receding tides so that it remained at the surface of the water, closest to the strong rays of the sun.

Blue Mussel: This species of mollusc was more commonly found hollowed out, attached to seaweed or turnicates and crawling with different varieties of tiny baby shrimp. My group and I found a live baby mussel and larger mussel attached to the pier by the Barking Crab. It was shiny blue and ovular in shape. We opened it up with a knife to reveal a pale yellow squishy organism with a muscle like body part running along the seam of the shell.


Last year's photo of the underbelly of the harbor docks appears to be much less green than the sites I observed today. I see many colonies of Star Turnicates scattered throughout the area, which indicates that this site must be in brackish water. In all of the photos I have taken and seen of the harbor today, there was a thin, possibly 2 or 3 inch strip of green algae running along the edge of the docks where they meet the water. Unless the algae simply doesn't show up in this photo, it would appear that more has grown over this spring/summer season. In addition, there are large clumps of brown, black speckled algae like plants connecting everything on the dock, causing this section to jut out farther than the rest. There are also large shells mixed in there which might account for the volume of the section. Overall, this sample of last years growth seems less green but much thicker.

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