Shores
...rs and stores water for moisture to avoid desiccation. In the middle intertidal zones, mussels, whelks and starfish are common. Various algae, anemones, sea slugs and polychaetes dominate the lower tidal zones. Scavengers are usually found stalking the zones for food, including shore crabs and shrimps. The food web structure of Australia’s rocky shores is quite extensive. Like any food chain, organisms are divided into producers and consumers. Red, green and brown algae that develop on different zones of the rock platform provide food for many grazing animals. Photosynthesis is their form of reproduction. Phytoplankton drifting in the water is another main source for food. The changing tides and waves transfers seawater and debris over the shores which brings food to sessile and scavenger animals. Sessile animals use filtering methods to consume their food. The sessile animals, including mussels and barnacles are filter feeders Rocky shores are habitats where many consumer organisms depend on the producers. Consumers can be found in various locations of the rocky shores, including in rock pools, underneath rocks or on the rock platform itself. Grazers on the rock platforms include blue periwinkles, limpets and chitons. The herbivorous shells add to the food chain as carnivorous shells, including dog whelks, consume them. Dog whelks are capable of drilling holes through other small snails as an attack and ingestion method (Jensen, 2002). The scavenger animals explore between crevices of rocks for decaying animals or other material to feed upon. Various species of crabs and shrimps make up this category. To add even more to the food web, seabirds often feed upon the animals that inhabit the rocky shores. The physical environment of Australia’s rocky shores is extremely stressful, mainly because of the changes in weather and tides. Desiccation is the main problem for organisms that inhibit the rocky shores. Shelter underneath rocks or in crevices of rocks is resorted to for protection. Daily, the different zones are periodically submerged in salt water during high tide and emersed into an open-air environment during low tide (Underwood, 1995). The sun and wind also play major roles in desiccation of organisms that are located at high zones of the shores, unlike the lower zones where organisms have to face problems of competition for space and predation. The lower zones also have to be able to cope with the turbidity of waters and reckless wave action. The zones depend on the slope of the shore. Steeply sloped shores will present visible distribution patters while gentle sloping shores provide less distinc...