Natural England Research Report NERR009
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Natural England Research Report NERR009 The application of biological-effects tools to inform the condition of European Marine Sites www.naturalengland.org.uk Natural England Research Report NERR009 The application of biological- effects tools to inform the condition of European Marine Sites Tamara Galloway, William Langston, Josephine Hagger, Malcolm Jones Plymouth Marine Science Partnership Published on 3 July 2008 The views in this report are those of the authors and do not necessarily represent those of Natural England. You may reproduce as many individual copies of this report as you like, provided such copies stipulate that copyright remains with Natural England, 1 East Parade, Sheffield, S1 2ET ISSN 1754-1956 © Copyright Natural England 2008 Project details Natural England Contract No FST20-18-028 A summary of the findings covered by this report, as well as Natural England's views on this research, can be found within Natural England Research Information Note RIN009 – The application of biological-effects tools to inform the condition of European Marine Sites. Project manager Michael Coyle Natural England Northminster House Peterborough PE1 1UA [email protected] Contractor Tamara Galloway, William Langston, Josephine Hagger, Malcolm Jones Plymouth Marine Science Partnership Acknowledgments This project would not have been completed without the sterling technical support from Marie Hannam, Trevor Worsey, Mark Browne and Jim Hill (University of Plymouth), and Gary Burt, Belinda Chesman and Sean O’Hara (Marine Biological Association). Thanks are due to members of the steering group for advice and help during this project, notably, Michael Coyle, Jennifer Best, Mark Taylor, Roger Covey (Natural England) and Richard Owen (Environment Agency of England and Wales). The helpful contributions of others are also gratefully acknowledged, particularly Peter Jonas and Rachel Hudson of the Environment Agency (South West Region) for supplying recent water quality data. Thanks also to the PREDICT team for access to their unpublished findings. It should be noted that the opinions expressed in this report are largely those of the authors and do not necessarily reflect the views of Natural England Tools to inform the condition of European Marine Sites i Summary A number of marine sites have been designated as Special Areas of Conservation (SAC) in England under the EC Habitats Directive. Natural England has a duty to monitor, report on the condition, and advise on risks to the features for which each site has been designated. Currently, methodologies for recording condition are based on ecological community-level census techniques, coupled with contextual information (which includes chemical and biological monitoring assessments), and expert judgement. The aim of this project was to assess the feasibility and value of developing a cost-effective and practical methodology based around biological-effects measurements (biomarkers) to assist in condition assessment of marine SACs, which could be deployed on a 6-year cycle. The Fal & Helford SAC and Plymouth Sound & Estuaries SAC were chosen as test sites for the deployment of such measurements. Within each SAC, sampling sites were chosen to reflect historical chemical contamination identified by a critical assessment of a series of desk-based site characterisation studies of European Marine Sites (EMS) in the south-west region. The sampling stations spanned a wide range of interest features in each of the SACs. The field surveys employed a suite of biomarkers incorporating molecular, biochemical, cellular and physiological endpoints applied to coastal invertebrate animals endemic to each SAC site (Mytilus edulis, Carcinus maenas). It was important that the species selected occurred at each sampling site. At the same time as taking biological endpoints, water was sampled from the collection sites and tested using the Microtox rapid toxicity bioassay. None of these samples was acutely toxic. Biomarker results suggested that there were sites within each SAC that experienced multiple contaminant impacts from PAHs, TBT and metals (and possibly, indirectly, from nutrient enrichment). Individual biomarkers that discriminated impact included metallothionein, TOSC and PAH metabolites. Taking all the individual biomarker evidence in an integrated biomarker assessment (Biomarker Response Index) indicated that, for the Tamar, mussels and crabs were impacted along a general gradient from Neal Point (highest impact) to Torpoint. For the Fal, the health status of crabs in the upper estuary was impacted (possibly due to elevated PAH concentrations) as was the health of mussels from Weir Point (possibly due to historical trace metals). TBT bioaccumulation in mussels from Penryn Creek and the continuing absence of dogwhelks in the Fal also imply that the condition of the site may be compromised in the Falmouth region. Despite relying mostly on historical chemical data, biomarker responses often related significantly to chemical hotspots and sources (eg reflecting Restronguet Creek as a source of metals in the Fal; signifying reduced water quality in the upper Fal, and lower Tamar). Equally important, there was usually consistency in characterising good water quality/reference conditions (Whitsand and Maenporth). This study showed therefore, that some individual biological techniques provide useful diagnostic information on the activity of certain classes of contaminants. In order to facilitate the interpretation of complex biomarker data sets to inform Natural England’s environmental risk and condition assessment procedures, a Biomarker Response Index (BRI) was developed. The BRI makes use of a range of “expected” reference values for the biomarkers, classifies the responses based on extent of deviation from reference, and weights responses according to the level of biological integration. The main benefit of the BRI is to provide a simple visual method of comparing integrated biomarker responses from field locations against normal reference responses. It also provides an alternative way of viewing the full biomarker dataset, providing an essentially similar picture to the integrated ii Natural England Research Report NERR009 assessment based on multivariate analysis, and allows a simple way to prioritise further investigative studies. For the Tamar, mussels from all sites showed major and severe alteration from normal health ranges; and crabs were impacted along a general gradient and in particular showed major alterations in normal baseline responses at Torpoint and Town Quay. For the Fal, the health status of crabs in the upper estuary was severely impacted as was the health of mussels from Weir Point. In addition, both mussels and crabs sampled from near Falmouth docks (Flushing) showed evidence of major alterations to their health. These results highlight the potential value of biomarkers in the overall scheme of site assessment, and several examples have been provided on where such information can strengthen Natural England’s current condition assessments (for the Fal), and thus help focus future action. Practitioners should, however, recognise some limitations in using biomarker tools to inform risk assessment and condition assessment; some of these can be reduced by tailoring methodology, sampling design, or by undertaking additional further work. These include: x The individual tools are not designed to be used on their own, but rather to form part of the weight of evidence in an integrated risk assessment. x Biomarker responses could be subject to subtle biotic and seasonal influences which would have to be factored in to any routine application of biological-effects tools. While the BRI takes such variation into account, by including studies incorporating different biotic and seasonal influences to set the range of BRI values where ever possible, it would seem that if comparison across sites is a management priority, sampling at a fixed time of year will be essential to avoid seasonal variation. x Lack of chemical data and detailed ecology measured at the same time as the biomarkers, requires a reliance on historical contextual data to link contamination and health status of exposed organisms. Acquisition of appropriate contemporary information on chemical and biological status, at common sites, should be seen as a high priority. x As this study has indicated, the environmental relevance of biomarker responses can be increased by using biomarkers from invertebrate species which occupy critical trophic positions, and by applying weight of evidence e.g. BRI techniques to interpret risks. However, additional work is required to understand what these biomarker responses mean for health of an individual, and how this can be extrapolated to the population. Tools to inform the condition of European Marine Sites iii Contents 1 Introduction 1 Background 1 Monitoring the effects of chemicals in the environment and developing biological-effects tools 1 Objectives 2 Application of biomarkers: The ECOMAN approach 3 2 Study sites 9 Selection of SACs 9 Rationale for selection of sampling stations within each SAC 10 Summary of existing contextual information on study sites 10 The Fal & Helford SAC 11 Plymouth Sound & Estuaries SAC 19 3 Methods 27 Species selection 27 Sampling programme 29 Biomarker selection 29 Statistical methods 30 Development of a weighted classification system 30 Weighted grading system (Biomarker Response Index) 33 4 Results 39 Examples of individual biomarkers 39 Metallothionein