Monitoring of Kelp Depth as an Indication of Turbidity in Pen Llyn a'r Saranac Special Area of Conservation (SAC) dataset https://portal.medin.org.uk/portal/start.php?tpc=007_NRW_DS111139 Turbidity provides an indication of water clarity and water quality. The depth to which light can penetrate is reduced with increased turbidity, which may be the result of natural processes in coastal and estuarine waters but can also be caused by anthropogenic causes such as coastal construction and dredge spoil dumping. Curvie (Laminaria hyperborea) is known to be susceptible to the impacts of elevated turbidity levels and therefore changes in L. hyperborea can be an indicator of changes in turbidity. Grazing of L. hyperborea by the common sea urchin Echinus esculentus may also have an impact of numbers of kelp plant and therefore numbers of this species present must also be taken into consideration. The purpose of this data capture was to use depth measurements for the distribution of kelp Laminaria hyperborea as a monitoring indicator for medium/long-term changes in turbidity level. Also to measure the overall 'luxuriousness' (biomass) of the algal turf of the rocky reef. This information will assist with reporting on the favourable conservation status of reef features in Pen Llyn a'r Sarnau. 20091231