JNCC Report No. 525 Marine Strategy Framework Directive Indicators for UK Kelp Habitats Part 1: Developing proposals for potential indicators M.T. Burrows, D. Smale, N. O’Connor, H. Van Rein & P. Moore September 2014 © JNCC, Peterborough 2014 ISSN 0963 8901 For further information please contact: Joint Nature Conservation Committee Monkstone House City Road Peterborough PE1 1JY www.jncc.defra.gov.uk This report should be cited as: M.T. Burrows, D. Smale, N. O’Connor, H. Van Rein & P. Moore. 2014. Developing Indicators of Good Environmental Status for UK Kelp Habitats. JNCC Report No. 525, SAMS/MBA/QUB/UAber for JNCC, JNCC Peterborough. Acknowledgements Michael T. Burrows (Scottish Association of Marine Science), Dan Smale (Marine Biological Association), Nessa O’Connor, Henk Van Rein (Queens University Belfast), Pippa Moore (University of Aberystwyth). This report has been produced through funding provided by members of the UK Marine Strategy Framework Directive Biodiversity Indicators Research and Development Funders’ Group. This Group was formed to assist with funding and oversee research required to develop biodiversity related indicators for the Marine Strategy Framework Directive and is supported by the Healthy and Biologically Diverse Seas Evidence Group (HBDSEG). The Funders’ Group consists of representatives from the Department for the Environment Food and Rural Affairs, Welsh Government, Department of the Environment for Northern Ireland, Marine Scotland, Joint Nature Conservation Committee and the Chair of HBDSEG. This project report has been reviewed by a Project Steering Group consisting of experts from the Statutory Nature Conservation Bodies. Marine Strategy Framework Directive Indicators for UK Kelp Habitats Part 1: Developing proposals for potential indicators Summary JNCC commissioned a consortium of the Scottish Association for Marine Science (SAMS), the Marine Biological Association (MBA), Queen’s University Belfast (QUB) and the University of Aberystwyth (UAber) to deliver an indicator that demonstrates the response to the main pressures acting on UK kelp habitats for the Marine Strategy Framework Directive. Section 1 provides a review of the information available to support the development of this indicator of Good Environmental Status, and includes a review of the proposed methods for defining and validating the indicator. Section 2 reports the development of this indicator of Good Environmental Status, and presents evidence underpinning the indicator based on the fitting of species distribution and habitat models for kelp species. Section 3 identifies major knowledge gaps and gives recommendations about survey designs and protocols that would make the kelp Good Environmental Status indicator operational in the UK. Knowledge of temporal variability in UK kelp populations is severely lacking, in direct contrast to kelp in other countries, notably the Californian giant kelp. This information is needed to allow the separation of natural (and anthropogenic) climate change and variability from acute and chronic pressures from human activities. Our proposed system of sentinel sites for annual monitoring of kelp should help alleviate this knowledge gap. Very little is known of the effects of direct human pressures on kelp populations in the UK. We review the evidence available from studies in the north-east of England in the 1970s and conclude that the effects of pollution are hard to disentangle from the effects of turbidity around urban and industrial centres. Inshore mapping data is also lacking, yet would considerably improve (i) the level of knowledge as to where kelp habitats might be expected to occur and their associated condition, (ii) the predictive ability of models by allowing surface characteristics to be factored in, and (iii) the ability to select survey sites for monitoring work. The authors recommend a two-tier approach to surveying and monitoring kelp habitats and kelp populations. This would be comprised of (i) a series of sentinel sites surveyed regularly (ideally annually), and (ii) broadscale surveys to assess the state of kelp populations between the survey sites. Details of the likely techniques and protocols are provided. A straightforward cross-calibration of different techniques for monitoring sublittoral kelp is required, along with an assessment of the efficacy of each technique in order for stronger recommendations to be made. This comparison should address questions of (i) accuracy, (ii) repeatability and (iii) representativeness. Development of Indicators of Good Environmental Status for UK Kelp Habitats Glossary ABP Associated British Ports BGS British Geological Survey DEM Digital Elevation Model GEBCO General Bathymetric Chart of the Oceans GES Good Environmental Status - for reporting for MSFD HSE Health and Safety Executive ISR The Institute of Seaweed Research MAREMAP Marine Environmental Mapping Programme MBA Marine Biological Association of the United Kingdom MNCR Marine Nature Conservation Review MOB Man Over Board MODIS Moderate Resolution Imaging Spectroradiometer MSFD Marine Strategy Framework Directive NAO North Atlantic Oscillation NASA National Aeronautics and Space Administration NBN National Biodiversity Network NCC Nature Conservancy Council NOC National Oceanography Centre QUB Queens University Belfast ROV Remotely Operated Vehicle SAMS Scottish Association for Marine Science SST Sea Surface Temperature Development of Indicators of Good Environmental Status for UK Kelp Habitats Contents 1 Kelp habitats in the UK – review of available information ....................................... 1 1.1 The status of UK kelp research 1 1.1.1 UK kelp research ............................................................................................. 1 1.1.2 UK kelp habitats ............................................................................................... 2 1.1.3 Kelp as a habitat for other species .................................................................. 6 1.1.4 Productivity and food webs .............................................................................. 9 1.2 Threats 10 1.2.1 Climate change .............................................................................................. 10 1.2.2 Top down – Grazers ...................................................................................... 13 1.2.3 Harvesting and cultivation .............................................................................. 13 1.3 Data on UK kelp 14 1.3.1 Historical data – The Institute of Seaweed Research .................................... 15 1.3.2 The Marine Nature Conservation Review ...................................................... 17 1.3.3 British Phycological Society mapping scheme .............................................. 17 1.3.4 Other datasets ............................................................................................... 17 1.4 Environmental drivers and pressures 18 1.4.1 Temperature .................................................................................................. 19 1.4.2 Water quality - Primary production and sediment load .................................. 19 1.4.3 Wave height and wave exposure ................................................................... 20 1.4.4 Other factors: Tidal flow, tidal range, geology ............................................... 22 1.5 Statistical methods 23 2 Developing indicators of Good Environmental Status for the Marine Strategy Framework Directive ................................................................................................. 24 2.1 MSFD Descriptors 24 2.2 The distribution of kelp and associated species along environmental gradients in the UK 24 2.2.1 The Marine Nature Conservation Review dataset ......................................... 25 2.2.2 Wave exposure and depth as the major axes of variation in shallow sublittoral communities ................................................................................................................. 25 2.2.3 Species associated with kelp distributed along wave action and depth gradients ...................................................................................................................... 27 2.3 Characterizing habitats for kelp species 30 2.3.1 Prediction data layers .................................................................................... 30 2.3.2 Wave fetch ..................................................................................................... 30 2.3.3 Temperature .................................................................................................. 32 2.3.4 Satellite chlorophyll a estimates as an indicator of light attenuation .............. 34 2.3.5 Other potential predictors, including depth .................................................... 35 2.3.6 Covariation among environmental predictors ................................................ 35 Development of Indicators of Good Environmental Status for UK Kelp Habitats 2.3.7 Summary: final selection of environmental predictors ................................... 36 2.4 Predictive models for kelp species 37 2.4.1 How can baseline predictions from models provide indicators? .................... 38 2.4.2 Models by species ......................................................................................... 41 2.4.3 Predictive habitat maps by species ............................................................... 46 2.5 Using predicted presence and abundance for assessment of