CEFAS24-135 Contract for a ground truthing survey of The Wash and approaches

The Marine Protected Area (MPA) monitoring programme is funded by the Department for Environment, Food and Rural Affairs (DEFRA) and through this programme, Cefas co-ordinates some of the evidence collection for the monitoring of MPAs in English waters.

The Ross Worm Sabellaria spinulosa is a sedentary, epifaunal polychaete worm which builds tubes by consolidating particles of sediment (Limpenny et al, 2010).

S. spinulosa is abundant in UK waters, largely existing in solitary form or within small, low-lying aggregations (Hayward and Ryland, 1990).

However, under the right environmental conditions they also can establish dense colonies and form biogenic reefs.

These biogenic reefs are protected as an Annex I habitat under the EU Habitats Directive (EEC, 1992), and Special Areas of Conservation (SACs) are designated for their protection.

Important areas of consistently occurring reef have been found across The Wash where extensive areas of subtidal mixed sediments in the tide-swept approaches provide the right conditions for reefs to form, particularly in deeper waters.

These reefs are an important but understudied feature of both The Wash and North Norfolk Coast (WNNC) SAC and Inner Dowsing, Race Bank and North Ridge (IDRBNR) SAC - named as 'The Wash and its approaches' hereafter.

Requirement: With the aim of improving our understanding of the extent, distribution, and nature of S. spinulosa biogenic reef (i.e. reefiness) across The Wash and its approaches, Cefas are commissioning this contract to deliver a ground truthing survey.

The evidence gathered in this acoustic survey will seek to allow for the identification of Annex I S. spinulosa reefs.

This evidence will be used to support conservation advice, condition assessment and management of the WNNC SAC and the IDRBNR SAC, its designated sites and protected features, i.e.

Reefs (including S. spinulosa biogenic reef) habitat.

This information will inform statutory advice on MPAs and assist in the assessment of both SAC sites' condition.