Introduction

Project Content and Study Aims

subtidal hard substrata in temperate waters resemble coral reefs in the tropical marine realm in that they support the highest diversity of marine organisms for these regions - organisms which for the most part require attachment to a hard surface. Algal dominated communities typify the shallower infralittoral zone, typically down to ten or twenty metres, whilst the deeper circalittoral zone is largely animal dominated. It is the latter group of organisms - ‘circalittoral faunal turfs’ (CFTs) - which provides the focus of this particular volume of the UK Marine SAC Project’s activity on reviewing sensitivity for selected biotope complexes.

CFTs were chosen as a target group for Task 1.1 study because they:

- have high biodiversity;

- comprise a major portion of the UK nearshore hard-substratum habitat;

- are vulnerable to some natural and anthropogenic impacts; and

- have been poorly studied until recently, and though recent developments in diving and submersible technology have widened understanding, there is still an urgent need to bring existing information to the forefront of applied science and the marine conservation arena.

The audience for this report is typically marine resource managers working at a site level. Therefore, this report summarises existing knowledge on CFTs with particular emphasis on achieving a greater understanding of the ecological dynamics and sensitivity of this biotope complex, through the following:

a) examining the fundamental environmental, physical, biological and ecological features of CFTs;

b) assessing CFT sensitivity to natural phenomena and anthropogenic impacts; and

c) exploring options for monitoring and information-research gaps that are relevant to the management of CFT communities in marine SAC areas.

Nature and Importance of Circalittoral Faunal turfs (CFTs)

Distribution of CFTs

References