Maerl habitat mapping Project 2025-26: Fal and Helford SAC

Natural England seeks contractors for an acoustic and drop-down video (DDV) survey in Autumn 2025 to collect high-quality data on maerl habitat within the Fal and Helford SAC overlapping the Falmouth Bay to St Austell Bay SPA. This data will assess the extent, quantify live vs dead subtidal maerl, verify acoustic survey results, analyse data, produce a report, and import datasets into Marine Recorder Online.

Estimated contract value: £59,998 (including VAT)

Contract period: September 2025 - February 2026

Fieldwork completion: by 30 November 2025

Location: Fal and Helford SAC overlapping area of Falmouth Bay to St Austell Bay SPA and Manacles MCZ, Cornwall

Opportunity Details

The objective is to analyse data on the distribution and extent of subtidal maerl communities to provide evidence for assessing site changes and monitoring future changes. This will also provide baseline information on maerl habitats within the remaining Falmouth Bay to St Austell Bay SPA areas overlapping Fal and Helford SAC.

Suppliers will be expected to:

Conduct sidescan sonar and DDV surveys assessing maerl habitat extent, distribution, and condition in Falmouth Bay and Carrick Roads, following NMBAQC guidelines and building on prior work (2021-24).

Analyse stills and video to assess % cover of live and dead maerl, habitat types, and boundaries in line with MEDIN and NMBAQC standards.

Compare results with existing datasets (e.g., CIFCA, Envision surveys) to inform condition assessments.

Produce GIS-compatible habitat maps and metadata, including confidence assessments and QA (minimum 10% of data).

Supply a technical report, Marine Recorder-ready data, and a sampling plan for Natural England approval before fieldwork.

Supplier Requirements:

Proven expertise in marine habitat mapping, particularly maerl or similar benthic habitats, using acoustic and visual survey methods.

Access to appropriate survey vessels and equipment (sidescan sonar, DDV), either owned or subcontracted, meeting NMBAQC and MEDIN standards.

Capability in image and video analysis following NMBAQC's 'Epibiota Remote Monitoring' protocols, quantifying live and dead maerl per Axelsson (2023) categorisation scheme.

Experience delivering detailed technical reports with GIS maps, confidence assessments, MEDIN-compliant metadata, and QA standards (≥10% image QA).

Strong project management to meet deadlines and deliverables by February 2026.

Procurement Process:

A Request for Quotation (RFQ) with scope, deliverables, and evaluation criteria will be issued. The tender window will remain open for a minimum of three weeks. Questions will be answered via the designated procurement platform.

Contract Award Target Date: 1st September 2025