Star Seasquirt – Botryllus spp
Individual Star Sea Squirts are only very tiny animals measuring 2 mm long and cannot live on their own. Instead they arrange themselves in star shaped colonies, on rocks or seaweed on the shore and in the shallows, in a communal gelatinous casing which can cover an area up to 15 cm across. This casing is called a 'tunic' or 'test' which encrusts the substrate. At the centre of each star is a shared exhalent opening through which water is expelled. The colonies very greatly in colour and may be green, violet, brown or yellow with the individuals having a contrasting colour to the test.
Light Bulb Seasquirt - Clavelina lepadiformis
Light bulb sea squirts are conspicuous translucent animals living in colonies attached to rocky substrate and growing up to 20 mm in height. They are a delicate sublittoral species which are very sensitive to exposure by the tide. The animals brood their eggs and young within the 'body' cavity which can be seen by the naked eye. The animal gets its name from white lines, which are present around the opening of the seasquirt and in the body cavity as long lines extending from the top to bottom which give the seasquirt a light bulb appearance.
Ross Bryozoan - Pentapora foliacea
It is not actually a coral but rather a sea mat. Sea mats are a class of mostly marine animals found around the whole of the British Isles. They consist of many individual animals living in small box-like compartments forming part of the skeleton made from limestone, or sometimes a material similar to your nails. This skeleton forms a large complex structure which can help attract and trap food-carrying water. Each individual animal has a finely formed crown of tentacles for collecting the finely suspended food particles from the water. The Ross coral is a rust-red in colour with large colonies having a shape which resembles a human brain. This shape merely allows more water to be trapped in the complex structure allowing more food to be trapped and consumed. Ross corals are very brittle and easily damaged, especially by activities such as crab potting and divers kicking them with their fins.