In our first environmental systems lab we went down to the college docks to examine the ecosystem of its protective rubber skirt. Pearson College is located on the northern shore of Pedder Bay, at the southern end of Vancouver Island. The bay is open to the southeast to Juan de Fuca Strait. It has a rock shoreline and is about 10 meters deep. It has tides of up to 3.3 metres, with the waves of up to 2.5 metres in extreme. The weather conditions around Pedder Bay are not at all severe - with usually wet and mild winters and cold and dry summers, with very low annual temperature amplitudes. Due to their southern exposure, the docks receive a fair amount of direct sunlight.

Purpose of this lab

The purpose of this lab is to model the structure and function of the Pearson College docks' fouling system

Biotic structure

(i) Species list

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animalia: - mussles (about 20-30 encountered), - barnacles (80-90), - limpets (1), - haliclona & halochondria, - isopods, - small fish. plantae: - ulva, - filamentous diatom

(ii) Distribution

a) horizontal:

In the research area, the species are scattered evenly, with a slight concentration of ulva and phylumentus towards the eastern end.

b) vertical:

The topmost layer is formed mainly by mussles, barnacles and the limpet with some of the ulva. The central layer contains the majority of the ulva as well as the sponges. The predominant specie of the bottom layer are the diatoms.

(iii) Material from external sources

- pine needles, - leaves

Abiotic Factors

(i) Temperature

- water temperature: 12 degrees Celcius,

- air temperature: 14 degrees Celcius.

(iii) Light Intensity and Quality

The experiment was performed on a grey day with poor light and dull light quality. Although, due to its southern exposure, the system receives much direct sunlight over the day.

(iv) Tidal Height

The tidal height at the time of the experiment was approxiamately 1.2 m

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This page was created by: Meredith Shaw, Monica Maria Leonardo Segura, Rocio Gil Martinez de Escobar, Vee Chansa-Ngavej and Kuba Fast, first-year students of Lester B. Pearson College of the Pacific under the supervision of Garry Fletcher, the environmental systems teacher on September 20th 1997.

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