hat are the most common here, Fucus spiralis and Pelvetia canaliculata have adaptations to survive in this area.
This region of the shore lies between the MHWN and MLWN marks, and will be submerged for half of every day, even during neap tides. The most common seaweed in this zone Fucus vesiculosus. Mussel beds will form and both limpets and periwinkles will graze the rocks. Sea anemones and crabs are residents of this zone.
This region of the shore lies between the MLWN and ELWS marks, and will be submerged for most of each day, even during neap tides. The most important seaweed in this area is Fucus serratus, which will form large zones wherever suitable. It shows the greatest species diversity of any zone on the seashore.
This part of the shore lies below the ELWS mark, and is therefore never uncovered by the sea.
There are many types of organism found on the rocky shore. The two main photosynthetic organisms are the lichens and the macroalgae or seaweeds.
Lichen are the main organisms found in the splash zone and come in three distinct types; crustose, foliose and fruiticose.
Crustose lichens form a thin crust on the rock surface, and are impossible to remove without damage. Foliose lichens are leafy lichens that are not as firmly attached to the rocks. Fruiticose lichens extent vertically from the rock surface, and can sometimes be confused with mosses and small grasses. The leafy part of a lichen is known as the thallus.
Seaweeds are primarily divided by colour, into brown, red and green groups. Most marine seaweeds are brown seaweeds, with fewer red species, and even fewer green species. The three main parts of a seaweed are:
1. Frond (lamina, thallus, blade) (often broad and flat)
2. Stipe region (often long and cylindrical)
The frond or thallus is the site of most of the photosynthetic activity in the organism, and also contains the reproductive organs.
The stipe region can act either as a struc...