Species List:
- Barnacles
-Mussels
-Ulva (Green Algae)
-Limpets
-Seaweeds
-Halochondria (Yellow Sponge)
-Red Filamentous Algae
-Obelia (Something Whitish)
-Isopods
-Little Fish
-Gulls
Abiotic Factors:
 -Douglas Fir Needle
-Ocean Spray Leaves
-Boats (wake and oil residue)
-Guano (contains nitrogen and phosphates)
Observations:
During this lab, we observed the interaction of several marine species. In addition to observing organisms feeding on other organisms (ie: barnacles on plankton, harbour seals on herring or anchovies), we also observed organisms involved in symbiotic relationships. For example, we observed barnacles anchored to limpets. The relationship results in mutual benefit as (a) the barnacles are able to anchor themselves, alleviating problems that could result from "swimming free", and (b) the barnacles help to discourage predators that could potentially prey on the limpets. There are several other biotic factors that affect the system, including "guano" produced by seagulls that, as it contains phosphates and nitrogen, helps to maintain the balance of nutrients within the system.
We also observed numerous abiotic factors that could , and in all likelihood do, affect the lives of the living organisms. These include the temperature of the water, a factor that helps to determine which organisms can survive in the system; the amount of sunlight to which the system is exposed, a factor which affects the plankton, algae, and seaweed populations; and the salinity of the seawater. Human activity also plays an important role in the system. The wake from boats, pollutants from human sources, and the number of fish caught by commercial fishing fleets and recreational anglers all affect the processes of the system.
It is unlikely that the processes within the system are constant. Seasonal disparities in sunlight, temperature, and animal and human population in and around the system indubitably affect the many of the qualities of the system. For example, a sudden rise in the seagull population could upset the delicate nutrient balance in the system. This sudden change, coupled with favourable amounts of sunlight and warm temperatures, would precipitate a large algae "bloom". The rise in the seagull population could be a direct result of a drop in the seal population, thus eliminating competition between the two species over their common food source: fish. The decline in the seal population, in turn, could be the result of human economic factors: pollution from seaside industrial projects, or the massacre of seals resulting by fisherman angered by low salmon returns. Thus, abiotic factors that fluctuate throughout the year have a profound impact on the processes of the system and, by extension, on the organisms therein.
Visibility is an indicator of light penetration and is, therefore, an important quantifiable abiotic factor. One uses a Secchi dish to quantify visibility; on September 19, 1997, the Secchi dish was visible to a depth of 3.5 metres. However, in winter, this figure would increase because of the lack of plankton and algae in the frigid water. Human activity on the periphery of the systemwould also have an effect on the visibility; fertilizers carried in runoff from seaside farms could upset the nutrient balance of the system, perhaps creating an algae "bloom" (decreased visibility), while large falls of "acid rain" could adversely affect the pH level within the system, killing off the algae/plankton. The second scenario has occurred in parts of Ontario, creating lakes that are "crystal clear".
The action of waves and tides have an effect on the system and its member organisms. Tides and waves "flush out" the system, thus helping to maintain the nutrient levels necessary for the survival of organisms within the system. Without tide and wave action, the water in the system would become stagnant. Nutrients, such as nitrogen, would accumulate in the stagnant water, fertilizing algae and other marine plants. While tide action is fairly easy to quantify, the quantification of wave action poses a challenge. One could determine the regularity of waves by counting the number of waves the pass a certain point in an hour (day, month, year) and divide by the number of minutes (hours, days, months) to derive an average. It could also be useful to determine the average height of waves passing a point, or the force with which these waves strike a dock. These would all aid in the quantification of wave action.
Forrest, Eri, Kelly
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