West of Walney Marine Conservation Zone (MCZ) Monitoring Report 2018: Marine Protected Area (MPA) Monitoring Programme.
Abstract
This report is one of a series of Marine Protected Area (MPA) monitoring reports delivered to Defra by the Marine Protected Areas Group (MPAG). The purpose of the report series is to provide the necessary information to allow Defra to fulfil its obligations in relation to MPA assessment and reporting, in relation to current policy instruments, including the Oslo-Paris (OSPAR) Convention, the UK Marine and Coastal Access Act (2009) and Community Directives (e.g. the Habitats and Birds Directives and the Marine Strategy Framework Directive). The Statutory Nature Conservation Bodies (SNCB) responsible for nature conservation offshore (between 0 nm and 12 nm from the coast) is Natural England (NE). NE utilise evidence gathered by targeted environmental and ecological surveys and site-specific MPA reports in conjunction with other available evidence (e.g. activities, pressures, historical data, survey data collected from other organisations or data collected to meet different obligations). These data are collectively used by SNCBs to make assessments of the condition of designated features within sites, to inform and maintain up to date site-specific conservation advice and produce advice on operations and management measures for anthropogenic activities occurring within the site. This report, as a stand-alone document, does not therefore aim to assess the condition of the designated features or provide advice on management of anthropogenic activities occurring within the site. Anthropogenic pressures and their interaction with the data reported on here are considered by SNCBs at a later stage as part of condition assessment and management advice for this site. This report includes recommendations which inform continual improvement and development of sample acquisition, analysis and data interpretation for future survey and reporting. Site and feature specific indicator metrics are not currently defined for this site. Potential indicators, where identified, will be evaluated and considered for inclusion in recommendations for future reporting. This monitoring report is informed by data acquired during a dedicated survey carried out at West of Walney MCZ in 2018 and by NE and Bangor University in 2016, which will form part of the ongoing time series data and evidence for this MPA. West of Walney MCZ is an inshore site located off the coast of Walney Island, Cumbria within the 'Irish Sea' Charting Progress Area. The MCZ was designated in 2016 to protect the habitat Feature of Conservation Importance (FOCI) 'Sea-Pen and Burrowing Megafauna Communities' and the Broadscale Habitats (BSHs) 'Subtidal sand' and 'Subtidal mud'. This report provides a characterisation of the BSHs present in a northern section of the MCZ in the form of an updated habitat map and assessment of the infauna communities. The report also presents additional evidence on the presence and distribution of the FOCI within that region. For the area surveyed, the site is predominantly 'Subtidal mud' with a gradual coarsening of the sediment to the east, where 'Subtidal sand' is also present. There was some evidence of differences in infauna communities between the two BSHs with measures of diversity and total biomass generally higher in 'Subtidal sand' samples. However, a reliable characterisation of the BSH 'Subtidal sand' was not possible due to the limited number of samples of this class. While the survey was not designed to sample the habitat FOCI 'Sea-Pen and Burrowing Megafauna Communities' by confirming the presence of species which are thought to be indicative of this FOCI, this report provides evidence of the presence of 'Sea-Pen and Burrowing Megafauna Communities'. All samples that were classified as 'Subtidal mud' were observed to have species indicative of this habitat FOCI, suggesting this habitat is widespread across the area of interest. However, monitoring the health and changes in extent of these communities would require additional surveys that specifically target the epifauna of the seabed. A comparison of infauna assemblages collected from different sampling gears indicated that the larger Box core identified a more diverse and abundant assemblage than the Day grab. The Day grab sampled the same dominant taxa but in fewer numbers, while the Box core collected more burrowing species. These findings need to be considered for planning of future monitoring of the MCZ. Further recommendations for monitoring have been outlined within the report.