The kelp forest ecosystem at Petticoe Wick Bay lat 55 55’N. Long 2 09’W: an ecological study

The sub littoral vegetation at Petticoe Wick Bay Lat 55 55'N. Long 2 09'W. is described using two methods; a classificatory one (of the Zurich-Montpelier School of Phytosociology) and an agglomerative one (the Wisconsin Comparative Ordination Technique). Floristically distinct groups are extracted and discussed. Methods of measuring the net annual production of the dominant kelp Laminaria hyperborea (Gunn)Poslle and its associated epiphytes to assess their performance in relation to depth of submersion are presented and the results discussed. Data on the age structure of the community and infestation levels of Patina pellucida L is presented. The performance of L. hyperborea at three other sites is studied and compared to the results from Petticoe Wick.