2.04 Rocky Shores

What are rocky shores? They are the rocky area where sea meets the land.

How are organisms on a rocky shore distributed? Upper Shore, Middle Shore and Lower Shore.

What three types of bedrock are typically found in a rocky shore ecosystem? Bedrock consists of slate,granite, quartzite.

What are the different zones of the rocky shore?

1. High tide zone. This region is only flooded during high tides. Organisms that are found here areanemones, barnacles, crabs, isopods, mussels, sea stars, snails.

2. Middle tide zone. This is a turbulent zone that is unprotected twice a day. The zone extends fromthe upper level of barnacles to the lower area where large brown algae exists. Animals located hereare snails, sponges, sea stars, barnacles, mussels, sea palms, crabs, etc.

3. Low intertidal zone. This region is covered with water most of the time. It is uncovered when thetide is extremely low. The organisms that live here are not adapted to periods of dryness orextreme temperatures. Life in this are consists of brown seaweed, crabs, mussels, sea cucumbers,sea lettuce, sea urchins, shrimps, snails, tube worms.

The fourth upper zone is the splash zone.

What plants are found in each zone? Be specific on listing them

Splash- Lichens mosses and humus.

Upper- Blue-Green Seaweed, rockweed Selvetia compressa and Hesperophycus harveyanus

Middle- Rockweed – Silvetia compressa

Lower- Kelp, large brown algae including the feather boa (Egregia menziesii) and the sea palm(Eisenia arborea).

What is the name of a plant-like species found in rocky shores? Seaweeds and lichens.

In which zone of the rocky shore would you most likely find only grasses and patches of lichens? Splashzone.

What animals may be found in each zone?—be specific on listing them

Upper- above water anemones, barnacles, crabs, isopods, mussels, sea stars, snails-

Middle- mid-water snails, sponges, sea stars, barnacles, mussels, sea palms, crabs

Lower- deep water floor crabs, hydroids, mussels, sea cucumber, sea lettuce, sea urchins, shrimps,snails, tubeworms

What type of animal uses the rocky shore for their 'feeding' grounds? Birds

What factors shape the rocky shore?

The rise and fall from waves and tides. The waves break over the rocks and plants living there. As thetide falls, plants and animals are exposed by the air and adapt to time between the tides.

What special features of adaptations do each of these organisms living in the rocky shore have whichenable to survive this type of environment?

Seaweed (an algae) attaches to the rocks by hold fasts. Slimy mucus prevents them losing too much waterwhen tide is out and when seaweed is exposed to the sun.

Limpet has a muscular foot it uses to attach to a firm surface. They are also conical in shape to reduce thewave effect.

Barnacles are conical shape to adhere to rocks. They also adhere to surfaces.

Crabs use their legs to anchor on rocks. Hard shells protect them from being bashed against rocks andthey also use their legs to attach to rocks.

Lichens are salt resistant and also adhere to surfaces so they aren’t swept out to sea.

Sea Squirts filters food and oxygen from water using an oral siphon. They also live in groups and canreproduce by cloning or changes in sex.

What kind of 'resources' do organisms on a rocky shore compete for? Think about the physical factorsthat fluctuate for the rocky shore organisms. The organisms must compete for nutrients, space andlight.

Describe these three areas of the rocky shore:

The sealife and plants live between low and high tides in the intertidal zone. They are distributed intoseveral zones called platforms, rock pools, and boulder fields. The platforms are raised areas of rockthat drop to the water. Plants and animals live on the platforms where it is usually dry, but also on theareas in the water. Rock pools are areas where a small pool of water lies in a depression. This areaholds water like a small pond but if a wave comes along the boulder washes the sea life away. Poolshave grit in them and only some plants and animals can live in them. Finally, boulder groups are wherenot many waves occur and the shore is not too steep. However, during storms animals and plants canbe crushed by boulders that slip around.

Different habitats in the rocky shores create challenges for the species living there.