Intertidal Habitats

Intertidal muds (.PDF 35.74Kb) are restricted to the most sheltered coasts and sea loughs. A wide variety of invertebrate species occur within the sediments which are characterised by lugworm, ragworm, oligochaete worms, and molluscs such as Macoma balthica and, on the mud surface, the snail, Hydrobia ulvae. These invertebrates often occur in very high densities and are an important food source for large numbers of wintering waders.
Mudflats are often covered by extensive growths of eelgrass, which are particularly important for wintering wildfowl such as the pale-bellied brent goose. In other places extensive mussel beds occur, e.g. Lough Foyle and Belfast Lough.

Sandy, shingle and gravel shores (.PDF 71.22Kb) occur on more exposed shores and may appear barren. However, a number of species such as the isopod, Eurydice pulchra and a range of specialist burrowing amphipods and polychaete worms are characteristic of more sheltered sandy shores.
Rocky shores occur all around the coast of Northern Ireland. Taken as a whole, they are very diverse habitats with characteristic communities associated with different heights on the same shore.
 

Are often characterised by communities dominated by mussels and barnacles.

Have a mixture of communities dominated by barnacles, mussels, wrack and kelp. These are found on the Ards Peninsula, Lecale and the Mournes Coast. These areas are particularly important for wintering waders such as the turnstone  and the purple sandpiper.

Are often characterised by an abundance of the knotted wrack. Associated seaweeds include serrated wrack and on the lowest parts of the shore the kelp.
Sheltered shores are limited to sea loughs with Strangford Lough being an example that has habitats characteristic of extreme shelter where the free-floating form of knotted wrack has been recorded.