Mainstream Neart na Gaoithe Offshore Wind Farm Ornithology Technical Report June 2012 Brathens Business Park, Hill of Brathens, Banchory, Aberdeenshire, AB31 4BY www.natural-research.org C ORK ♦ E COLOGY Long Strand, Castlefreke, Clonakilty, Co. Cork, Ireland www.corkecology.net Contents 1 INTRODUCTION ..................................................................................................................4 1.1 Effects Assessed ................................................................................................................................................ 5 2 GUIDANCE, LEGISLATION AND POLICY CONTEXT ..................................................................6 2.1 Guidance ............................................................................................................................................................. 6 2.2 Legislation .......................................................................................................................................................... 6 2.3 Planning Policy and EIA Context ................................................................................................................ 6 2.4 Designated Sites ............................................................................................................................................... 8 2.5 Data Sources ...................................................................................................................................................... 8 3 METHODS ......................................................................................................................... 10 3.1 Baseline Surveys ............................................................................................................................................ 10 3.2 Data analysis methods ................................................................................................................................. 12 3.3 Impact Assessment Methods ..................................................................................................................... 12 3.3.1 The Approach to Impact Assessment................................................................................................................. 12 3.3.2 Sensitivity ....................................................................................................................................................................... 15 3.3.3 Evaluation of Nature Conservation Importance ........................................................................................... 15 3.3.4 Determining Significance under EIA .................................................................................................................. 16 3.3.5 Overall Significance .................................................................................................................................................... 17 3.4 Assessment calculations ............................................................................................................................. 18 3.4.1 Construction and Decommissioning effects .................................................................................................... 18 3.4.2 Operational Effects ..................................................................................................................................................... 18 3.4.3 Definition of Assessment Periods ........................................................................................................................ 18 3.4.4 Estimation of Potential Collision Mortality ..................................................................................................... 19 3.4.5 Estimation of Potential Displacement ............................................................................................................... 20 3.4.6 Estimation of Potential Barrier Effect ................................................................................................................ 22 3.4.7 Estimation of disturbance from vessels ............................................................................................................ 27 3.4.8 Connectivity to Designated Sites .......................................................................................................................... 29 3.4.9 Estimating Likely Realised Effects ...................................................................................................................... 31 3.1 Cumulative Impact Assessment Approach ........................................................................................... 31 4 BASELINE DESCRIPTION ..................................................................................................... 34 4.1 Survey effort .................................................................................................................................................... 34 4.2 Raw numbers of seabirds in the Neart Na Gaoithe Study Area in Years 1 and 2 .................... 36 4.3 Flight height of birds .................................................................................................................................... 37 4.4 Species Accounts ............................................................................................................................................ 41 4.4.1 Red-throated diver Gavia stellata ....................................................................................................................... 41 4.4.2 Northern Fulmar Fulmarus glacialis................................................................................................................... 43 4.4.3 Sooty shearwater Puffinus griseus ...................................................................................................................... 59 4.4.4 Manx shearwater Puffinus puffinus ..................................................................................................................... 68 4.4.5 Balearic shearwater Puffinus mauretanica ...................................................................................................... 72 4.4.6 European Storm-petrel Hydrobates pelagicus ................................................................................................ 73 4.4.7 Northern Gannet Morus bassanus ........................................................................................................................ 74 4.4.8 Cormorant Phalacrocorax carbo ......................................................................................................................... 95 4.4.9 European Shag Phalacrocorax aristotelis ........................................................................................................ 97 4.4.10 Common Eider Somateria mollissima ......................................................................................................... 99 4.4.11 Common scoter Melanitta nigra ................................................................................................................. 101 4.4.12 Grey phalarope Phalaropus fulicarius ...................................................................................................... 102 4.4.13 Red-necked Phalarope Phalaropus lobatus ............................................................................................ 103 4.4.14 Pomarine skua Stercorarius pomarinus .................................................................................................. 104 4.4.15 Arctic skua Stercorarius parasiticus .......................................................................................................... 105 4.4.16 Great skua Stercorarius skua ....................................................................................................................... 108 4.4.17 Little gull Larus minutus................................................................................................................................. 112 4.4.18 Sabine’s gull Larus sabini ................................................................................................................................ 126 4.4.19 Black-headed gull Larus ridibundus ........................................................................................................... 127 4.4.20 Common gull Larus canus ............................................................................................................................... 129 4.4.21 Lesser black-backed gull Larus fuscus ...................................................................................................... 133 4.4.22 Herring gull Larus argentatus ..................................................................................................................... 147 4.4.23 Great black-backed gull Larus marinus .................................................................................................... 166 4.4.24 Black-legged kittiwake Rissa tridactyla .................................................................................................... 182 4.4.25 Common tern Sterna hirundo ...................................................................................................................... 204 4.4.26 Arctic tern Sterna paradisaea ...................................................................................................................... 208 4.4.27 Common Guillemot Uria aalge ...................................................................................................................