The Fal estuary consists of a range of habitats including the rare and slow growing Maerl beds, Eelgrass beds and subtidal and intertidal rocky and sandy habitats. This gives the area a rich biodiversity, consequently it’s been allocated as a Special Area of Conservation (SAC) by DEFRA [6].
The Maerl beds are of significant importance, the two species found here Phymatolithon calcareum and Lithothamnion corallioides are home to a range of organisms and particularly important to juveniles and larvae, the coralline red algae provides perfect refuge [7]. The eelgrass is also a key nursery habitat. Both of the ecosystems these species help develop are very sensitive to environmental changes and are experiencing national decline. Frequent habitat mapping is crucial in identifying any changes in the area they cover and how we could mitigate any negative impacts upon them. This study looks at habitat mapping of the Maerl and Eelgrass beds around St Mawes using Dual Frequency Sonar and video analysis of the seabed.
