JNCC/Cefas Partnership Report Series Report No. 9 The Development of Monitoring Options for UK MPAs: Fladen Grounds R&D Case Study Murray, J., Jenkins, C., Eggleton, J., Whomersley, P., Robson, L., Flavell, B. & Hinchen, H. March 2016 © JNCC, Cefas 2015 ISSN 2051-6711 The Development of Monitoring Options for UK MPAs: Fladen Grounds R&D Case Study Murray, J., Jenkins, C., Eggleton, J., Whomersley, P., Robson, L., Flavell, B. & Hinchen, H. March 2016 © JNCC, Cefas, 2016 ISSN 2051-6711 For further information please contact: Joint Nature Conservation Committee Monkstone House City Road Peterborough PE1 1JY http://jncc.defra.gov.uk This report should be cited as: Murray, J., Jenkins, C., Eggleton., J., Whomersley, P., Robson, L., Flavell, B. & Hinchen, H. 2016. The development of monitoring options for UK MPAs: Fladen Grounds R&D case study. JNCC/Cefas Partnership Report, No. 9 This report is compliant with the JNCC Evidence Quality Assurance Policy http://jncc.defra.gov.uk/page-6675 and was peer reviewed by two independent experts and the JNCC project team. The Development of Monitoring Options for UK MPAs: Fladen Grounds R&D Case Study Summary In July 2014, 30 Nature Conservation Marine Protected Areas (NCMPAs) were designated in the seas around Scotland, of which 13 are located beyond 12 nautical miles. Introduced under the Marine (Scotland) Act (2010) for inshore waters, and the Marine and Coastal Access Act (2009) for offshore waters, NCMPAs have been introduced to ensure the full range of nationally important features in Scotland’s waters are represented in the MPA network. The Central Fladen NCMPA in the Northern North Sea has been designated for the protection of the burrowed mud feature, including both the seapen and burrowing megafauna in circalittoral fine mud, and tall seapen components, and for the sub-glacial tunnel valley representative of the Fladen Deeps Key Geodiversity Area. Burrowed mud habitats, such as those found within the Fladen grounds, are classified as moderately sensitive to shallow abrasion/penetration of the seabed, typically inflicted by bottom-contact fishing gears (Brooks et al 2013). JNCC and Cefas completed a survey in March 2014 to collect evidence to support development of monitoring options, specifically for the Central Fladen NCMPA and, more generally, for offshore mud habitats. The survey was designed to achieve multiple objectives, which are broadly described below: 1. Acquire data to comprise the ‘Before’ sampling event in a Before, After, Control, Impact (BACI) design (Type 3 monitoring) by surveying similarly sized areas inside (impact) and outside (control) a proposed Management Scenario Area in the Central Fladen NCMPA. 2. Acquire data on the benthic community characteristic of burrowed mud in the Fladen Grounds across a fishing pressure gradient determined using surface abrasion gridded data (Type 2 monitoring). 3. Collect benthic contaminant samples across the survey area to augment the information available regarding the level of organic and heavy metal contaminants in the sediment. 4. Establish the first datapoint in a time-series study across the burrowed mud habitat within the Fladen Grounds (Type 1 monitoring). The study aimed to investigate the effects of abrasive pressure inflicted by demersal fishing on the benthic communities across the greater Fladen Ground area through the testing of a number of biodiversity indices in a Type 2 monitoring approach. The indices found to be most appropriate for detecting meaningful change in habitat range, extent and condition in relation to increasing abrasion pressure would then be used to explore a potential management scenario within and around the Central Fladen MPA. Assemblage metrics and indices were selected with consideration for those being developed as part of Marine Strategy Framework Directive (MSFD) requirements and were tested in the context of Type 2 monitoring: change along an abrasive pressure gradient. Environmental variables such as sediment type and geochemistry, as well as aspects of community ecology such as infaunal and epifaunal species and assemblage metrics, Biological Traits Analysis, bivalve size frequency and Nephrops burrow densities were tested using data collected from the 2014 Fladen Grounds survey. Assemblage metrics were explored in relation to high- and low-abrasion pressure due to fisheries. In the high abrasion pressure boxes, a slightly higher silt/clay fraction was recorded and organic carbon and nitrogen and inorganic phosphate and total phosphate content were significantly higher. Analysis of variance identified a significant difference The development of monitoring options at UK MPAs: Fladen Ground between in infaunal assemblages between pressure blocks for a number of community metrics and when exploring biological trait composition, there were notable differences for several of the trait categories between abrasion pressure boxes suggesting that the communities are functioning differently in response to abrasion. Those within the high -abrasion areas contain higher relative abundances of burrow dwellers and subsurface deposit feeders, whereas surface deposit feeders and tube dwellers tended to be higher within the low pressure areas. However, due to inclement weather during the survey, the number and spatial spread of samples collected was reduced and it was therefore not feasible to draw broad conclusions on how infaunal community univariate metrics were responding to abrasive pressure across the whole Fladen Grounds. More data were available for epifaunal analysis allowing the testing of univariate metric responses of epifaunal assemblages across a gradient of abrasive pressure. Regression analysis showed that epifaunal communities are being modified by abrasive pressure, and generally speaking, with increasing abrasive pressure, the number of epifaunal individuals was reduced although species diversity increased. Seapen abundance and density varied across the identified pressure gradient with Pennatula phosphorea demonstrating a negative relationship with increasing abrasive pressure whilst Virgularia mirabilis showed no discernible relationship. The metrics tested in the Type 2 monitoring approach were used to provide the “Before” stage of a Type 3 BACI experimental approach around a management scenario area within and around the Central Fladen MPA. Sampling, using a random stratified sampling design, was conducted in a ‘Control Area’ (unimpacted by fishing) and an ‘Impact Area’ ( which in the future management scenario would be closed to fishing) which is at present hypothetically being subjected to the same influence of abrasion. As expected, no significant differences were found when comparing univariate metrics on infaunal assemblages collected at Control and Impact stations. However, when comparing the epifaunal assemblages, significant differences in taxon richness, number of individuals and Hill’s diversity were found despite multivariate analysis suggesting that assemblages from two treatments did overlap. Differences in the distribution of seapens across the experimental study area go some way to explain the differences in epifaunal univariate metrics. The present investigation provides baseline empirical data that could be used towards a range of biodiversity indicators in relation to areas of high- and low-abrasion pressure at the Fladen Grounds. Knowledge acquired from this study will be used to inform future monitoring of the area and contribute to monitoring options for offshore mud habitats more generally. Contents 1. Introduction ........................................................................................................................ 4 1.1 Project background ..................................................................................................... 4 1.2 Specific aims and objectives ....................................................................................... 5 1.3 Central Fladen NCMPA ............................................................................................... 5 1.3.1 Rationale for site designation ............................................................................ 5 1.4 Fladen Grounds habitat types at the UK scale ............................................................ 6 1.5 Overview of the Fladen Grounds ................................................................................ 7 1.5.1 Site boundary .................................................................................................... 7 1.5.2 Conservation objectives .................................................................................... 8 1.6 Relevant pressures to site features ............................................................................. 9 2. Type 1 monitoring - Spatial and temporal data ................................................................. 11 2.1 Introduction ............................................................................................................... 11 2.2 Methods .................................................................................................................... 11 2.2.1 Spatial patterns in particle size distribution ..................................................... 11 2.2.2 Spatial patterns in sediment geochemistry ...................................................... 11 2.2.3 Spatial distribution of seapens and burrowing megafauna .............................. 12 2.2.4 Contaminants analysis ...................................................................................