SCOTTISH MARINE AND FRESHWATER SCIENCE VOLUME 3 NUMBER 3 Clyde Ecosystem Review F McIntyre, P G Fernandes and W R Turrell Scottish Marine and Freshwater Science Report Volume 3 Number 3 Clyde Ecosystem Review McIntyre, F., Fernandes, P.G. and W. R. Turrell The Scottish Government, Edinburgh 2012 Marine Scotland is the directorate of the Scottish Government responsible for the integrated management of Scotland’s seas. Marine Scotland Science (formerly Fisheries Research Services) provides expert scientific and technical advice on marine and fisheries issues.Scottish Marine and Freshwater Science is a series of reports that publish results of research and monitoring carried out by Marine Scotland Science. These reports are not subject to formal external peer-review. © Crown copyright 2012 You may re-use this information (excluding logos and images) free of charge in any format or medium, under the terms of the Open Government Licence. To view this licence, visit http://www.nationalarchives.gov.uk/doc/open-government-licence/ or e-mail: [email protected]. Where we have identified any third party copyright information you will need to obtain permission from the copyright holders concerned. This document is available from our website at www.scotland.gov.uk. ISBN: 978-1-78045-877-9 (web only) ISSN: 2043-7722 The Scottish Government St Andrew’s House Edinburgh EH1 3DG Produced for the Scottish Government by APS Group Scotland DPPAS13075 (06/12) Published by the Scottish Government, June 2012 CLYDE ECOSYSTEM REVIEW McIntyre, F., Fernandes, P.G. and W. R. Turrell Contents 1. EXECUTIVE0B SUMMARY ............................................................................................... 4 1.1 Introduction ............................................................................................................. 4 1.2 Literature Review - Environment ............................................................................. 5 1.3 Literature Review - Biodiversity ............................................................................... 6 1.4 Literature Review – Non-Fishing Human Impacts ................................................... 8 1.5 Literature Review - Fishing (Pelagic and Shelfish) ................................................. 9 1.6 Heath and Speirs (2011) ....................................................................................... 13 1.7 A Management Data Tool ..................................................................................... 17 1.8 Suggestions for Future Work................................................................................. 19 1.8.1 Clyde Hydrodynamic Model ........................................................................... 19 1.8.2 Clyde Ecosystem Model ................................................................................ 20 1.8.3 Clyde Inshore Benthic Survey ........................................................................ 20 1.8.4 Clyde – an MSFD Development Area? .......................................................... 20 1.8.5 Clyde Pelagic Fish Stock Acoustic Survey ..................................................... 20 1.8.6 Clyde Demersal Fish Survey .......................................................................... 20 1.8.7 Improving the Clyde Management Evaluation Model ..................................... 21 2. INTRODUCTION1B ......................................................................................................... 22 2.1.1 An Ecological Desert - Thurston and Roberts (2010) ..................................... 22 2.1.2 A Changed Ecosystem - Heath and Speirs (2011) ......................................... 22 2.1.3 This Report .................................................................................................... 23 3. THE2B ENVIRONMENT OF THE CLYDE SEA ................................................................ 25 3.1 Definition11B of the Clyde Sea .................................................................................... 25 3.2 Geological History of the Clyde ............................................................................. 25 3.3 Bathymetry and Sedimentology ............................................................................ 26 3.4 Hydrography13B ......................................................................................................... 28 3.4.1 An42B Annual Cycle in the Clyde ......................................................................... 29 3.4.2 Warming43B Sea Temperatures .......................................................................... 32 3.5 Plankton14B ................................................................................................................ 32 3.5.1 Phytoplankton44B ................................................................................................ 33 3.5.2 Zooplankton45B ................................................................................................... 35 3.6 Concluding Remarks ............................................................................................. 35 3.7 Suggestions for Further Work ............................................................................... 35 4. BIODIVERSITY3B ............................................................................................................ 37 4.1 Background15B ........................................................................................................... 37 4.2 Benthic Fauna ....................................................................................................... 38 4.3 Maerl17B beds ............................................................................................................ 39 4.4 Seabirds18B ............................................................................................................... 40 4.5 Megafauna19B ............................................................................................................ 41 4.6 Threats20B to Biodiversity........................................................................................... 42 4.6.1 Invasive46B species ............................................................................................ 42 4.6.2 Climate47B change .............................................................................................. 42 4.7 Protection21B of Biodiversity ....................................................................................... 42 4.8 Suggestion for Further Work ................................................................................. 43 5. HUMAN4B IMPACTS (OTHER THAN FISHING) ............................................................. 46 5.1 Background22B ........................................................................................................... 46 5.2 Assessment23B of Pollution ........................................................................................ 47 5.3 Marine24B Litter .......................................................................................................... 52 5.4 Shipping25B ................................................................................................................ 52 1 5.5 26B Aquaculture .......................................................................................................... 53 5.6 Scotland’s Marine Atlas – Overall Assessment ..................................................... 54 5.6.1 Activities and Pressures ................................................................................. 54 5.6.2 Clean and Safe .............................................................................................. 55 5.6.3 Healthy and Biologically Diverse .................................................................... 55 5.6.4 Response / Forward Look .............................................................................. 55 5.7 Concluding Remark .............................................................................................. 56 6. HUMAN5B IMPACTS - FISHERIES ................................................................................. 57 6.1 Introduction27B ........................................................................................................... 57 6.2 Legislation28B ............................................................................................................. 57 6.3 Stock29B Assessment ................................................................................................ 59 6.4 Pelagic30B Fisheries................................................................................................... 59 6.4.1 Herring48B ........................................................................................................... 59 6.5 Demersal31B Fisheries ............................................................................................... 61 6.5.1 Cod49B ................................................................................................................ 63 6.5.2 Hake50B .............................................................................................................. 64 6.5.3 Saithe51B ............................................................................................................ 65 6.6 Shellfish32B fisheries .................................................................................................. 65 6.6.1 Nephrops52B ......................................................................................................