Collecting Samples
To catalogue the mutations (if any) in Littorina littorea from the North West Arm, I endeavored to find a sample of the same species in a pristine environment. Through research I discovered that Chester Basin is not only a healthy environment, but also contains the same geological features present at the North West Arm. The point of collection in this area was Graves Island. In this area I found 124 periwinkles along a 30-meter stretch of coastline. It was evident that the ecosystem was intact, as I also noted the presence of dolphins, a large variety of fish, sandpipers, herons, and jellyfish. I also noted that the periwinkles in this environment appeared on rocks far from the waterline and did not react to exposure to light. From this environment I collected five periwinkles, as well as two liters of water and 0.25 kilos of sand.

My first point of collection along the North West Arm was near the main sewage outlet at Point Pleasant Park, on a foggy evening in April. I combed the shores for two hours (at low tide) and found only four periwinkles. However, the abundance of periwinkle shells indicated that the population must have been more pervasive at other times. I returned the following day at high tide and found no presence of periwinkles, and even the broken shells had been washed out to sea. On both occasions I collected water samples in sterile containers, which I later tested for pH level, turbidity, and the level of chlorine present. I returned to this area on a sunny day when the amount of bacteria in the water is known to be lower. I found few traces of periwinkles at either high or low tide.

On a bright May evening one week later, I examined the beach near a secondary sewage outlet along Jubilee Road; this is also the location of a popular recreation area, the Saint Mary's Boat Club. At first, the only traces of periwinkles were scattered shell remains on the beach. After further investigation, however, I found 12 common periwinkles along a 30-meter stretch of beach. Along the same stretch of beach were several pounds of dehydrated black seaweed and an abundance of garbage. The 12 periwinkles were all found suctioned to the bottom of a large igneous rock two meters from the waterline. I collected three of these periwinkles, as well as one stalk of green seaweed, 0.5 kilos of igneous rock, 0.25 kilos of sand, and two liters of North West Arm water. I then arranged the contents in a 20-liter tank.

I returned later in the week, during inclement weather, to collect another sample of water. This was to document the changes in concentrations of fecal bacteria, metals, and PCBs to give a more accurate picture of the Arm's environment.