Aim:
To investigate the distribution of two different species of barnacles, the acorn barnacle (Chamaesipho columna) and the brown barnacle (Chamaesipho brunnea) at low, mid and high tide. The data collected is from Siren’s Rock, Island Bay. This will be done by looking at both the abiotic and biotic factors of their environment. Barnacles are under the crustacean family, the same family as crayfish and crabs (Ultimate Visual Dictionary of Science). The pattern found on the rocky shore was a zonation pattern.
Primary Organism:
The adult acorn barnacles are sessile, the cone shaped shell comprises of six calcareous plates. This volcano shape has a basal part, which keeps it cemented to the rock. There are six non-movable plates around the barnacle and two on top that are movable so the barnacle is able to seal itself from the outside environment when it is under threat or in danger. Also for when the tide goes out, these protect the barnacle from desiccation (dehydration) as it holds the moisture inside. These two movable
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There very rough water. Both the acorns have hard shells and are cemented to the rock. Because the brown barnacle is at high tide it is less likely to be affected too much by the tide, but it is still very possible. Therefore both barnacles need to be protected from this. (Smith, 2013)
Sun/Temperature: The acorn and brown barnacle need to be able to survive despite the sun and hot temperatures. The acorn barnacle can hold moisture but not as well as the brown barnacle. Therefore the acorn barnacle’s ideal zone is the low tide and the brown barnacle is the high tide zone. The brown barnacle is almost double the size of the acorn barnacle, which is why it can hold more moisture and survive in the sun for longer. (Smith, 2013)
Description of