Monday, August 3, 2009

Lovells Island

Sunday turned out to be a beautiful day despite the early clouds. On Lovells Island we talked about many things: beach types, Brazil Nut Phenomena, periwinkles, tidal pools, black back gulls, and sand pippers just to mention a few topics. While we were talking about the periwinkles we came up upon our first question; what animal preys on the periwinkles, digging a hole through its tough shell? My first idea was that the holes were caused by the same birds flying around the island and after further research I discovered that green crabs also prey on periwinkles. Those birds (black back gulls, white birds and sand pippers) were found at the tidal pool along with many green crabs. While we walked on the beach we found a lighter brown colored snail shell, not like the black shell of the periwinkles, this discovery brought us to our second question; how did these shells get here from te inner island? My theory is that the birds that prey on them may have dropped the shells from the sky. On Lovells Island we found all different types of snails and I think that they are all related and I explain the difference in colors as a defence mechanism. For example, the periwinkles found by the rocky portion of the beach have a black shell to blend in with the rocks and the lighter brown snails found on the stems and leaves of the plants in the inner island blend in with their respective sorroundings.
On Saturday our setting was totally different from Sunday's setting. On Saturday we were looking at walls and other man made structures (tidal walls, docks) and how the living organisms like Tunicates adapt to these surroundings and how these species manage to survive. On Sunday we explored flat surfaces and more natural settings like the beach.

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