ocean Ecology of Atlantic Shores ~

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Study Sites:
Sediment samples were collected at two sites in Bermuda, Whalebone Bay and Tobacco Bay. Both Bays are on the northwhalebone bay shore of the island. The beach at both bays was covered in a layer of seaweed.

Sediment samples were also collected at two locations in New England, Nahant MA and Rye NH. Samples from Nahant were taken at Pumphouse beach on the south shore. Sediment at this beach was relativley coarse and difficult to obtain due to the rocky nature of the area.

Samples from Rye were taken at a salt marsh in Odiorne Point State Park. The sediment there was a fine, densely packed mud containing dead vegetation.


Collection:
At Whalebone four samples were collected. Two samples were taken about a meter above the average line where the waves were breaking and two samples were taken a meter below that point. At Tobacco Bay six samples were taken. Two were taken about a meter above the breaking line, two were taken two meters below the breaking line, and two were taken four meters below the breaking line. Sediment was collected in plastic containers and taken back to the lab for examination.

At Nahant and Rye core samples were taken using a clear plastic tube with a one inch diameter. The tube was marked at five and ten cm from the bottom. This way samples could be divided into two categories; 0-5cm deep and 5-10cm deep. Samples were taken at low tide at random locations in the intertidal zone. Samples were transported back to the lab in labeled ziplock bags.

Extraction:
In Bermuda, to extract the organisms the sediment was rinsed with fresh water, mixed, and then that water was poured into a large petri dish. The invertebrates were then observed in the petri dish under a microscope. Organisms were then transferred to a smaller petri dish or slide to be photographed for later identification.  The first ten living organisms found in each sample were recorded. In some cases less than ten organisms were found.

Organisms from Nahant and Rye were extracted using a different method. Sediment samples were mixed with MgCl to relax the animals and make extraction easier. The solution was mixed and poured through a sieve. Organisms were rinsed from the sieve into a pretri dish using filtered sea water. This process of mixing and filtering was repeated three times for each sample. A grid of 0.5cm by 0.5cm squares were drawn on the bottom of each petri dish. Twenty squares were randomly selected and all organisms in those twenty squares were recorded and identified.