| Results and Observations | ||
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The distance of P. Lanosa from the hold fast on the stipe of Ascophyllum was no less than 12cm. Individual clumps of P. lanosa ranged in size from less that 5mm to more than 35mm. There was no clear correlation between the distance of P. lanosa from the hold fast and the size of the P. lanosa individuals. In addition to Polysiphonia lanosa there was another epiphytic algae present, the brown algae Pilayella littoralis. I had not expected to see this epiphyte and therefore did not gather any data on its position or size. I did however examine a clump of it under the microscope and observed high densities of marine mites present in its hair-like mass. Another observation of interest was the diversity of species found within damaged pnuematocysts on the Ascophyllum stipe or lateral branches. As many as six Littorina obtusada juveniles were found within one injured pnuematocyst. Other organisms were found including small Mytilus edulis mussels, colonial polychaetes, a potato sponge, bryozoans, and some other unidentified organisms. Fucus spiralis was found attached to the broken tip of a few Ascophyllum stipes. The broken tips, in these cases also supported a large population of P. lanosa. The number of lateral branches off the main stipe of Ascophyllum ranged from 3 to 33. The number of lateral branches significantly effects the number of P. lanosa clumps present on the stipe (P = 0.003) see fig 1. This result is congruent with observations made during data collecting that many P. lanosa individuals attached to the main stipe at the origin of lateral branches. The number of P. lanosa present on the samples was significantly related to the length of the stipe (P = 0.0013), as well as the tidal height (P = 0.02). The slope of regression lines differed between tidal heights (fig. 3). The relationship between the least mean squares of P. lanosa abundance at different tidal heights indicate that low tidal height samples have significantly different P. lanosa abundance from those found at mid and highest tide (table 1, fig 4). The abundance of epifauna observed through microscopic inspection was compiled into a table combining taxa into general groups to decrease complexity (Table 2). The presence and abundance of epifauna varied across tidal height and differed between taxa. Marine mites were most abundant in the low and mid inter-tidal (fig. 5), while protists were most abundant at high tide (fig. 6). Nematodes were rarely seen in the low inter-tidal and more often observed in the mid, high and highest tidal heights (fig. 7). Crustaceans were fairly evenly distributed throughout the inter-tidal with slightly fewer present in the high tidal height (fig. 8). Mollusks and gastropods were most abundant in the high tide zone with relatively few individuals present in the highest, low and mid tidal zones (fig. 9). Overall, mid and high tidal heights had the highest number of epifauna present (fig. 10).
INTER-TIDAL RESIDENTS
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