Marine Habitats
The marine life in the seas surrounding Northern Ireland is extremely rich and varied. It can be subdivided into Intertidal and Sub-tidal habitats and the Open Sea. The plant and animal communities occurring are influenced by a number of physical and chemical factors, the most important of which are: 
- substrate which includes rock (including bedrock, boulders, mixed cobbles and pebbles) and sediments (muds, sands and mixed sediments)
- height above or below low water mark
- exposure to wave action
- tidal currents
- salinity (i.e. salt content)




