Baseline report for the monitoring of the marine ecology in relation to the building of the gas pipeline and outfall in Broadhaven, Co.Mayo - Pre construction survey (June – July 2005) Prepared for: Shell E & P Ireland. 27 July 2005 By: Ecological Consultancy Services Ltd (EcoServe) B19 KCR Industrial Estate Kimmage Dublin 12 www.ecoserve.ie Marine ecology of the landfall and crossings - pre construction survey (June – July 2005) Print name Signature Prepared by: Chris Emblow Checked by: Roisin Nash Authorised by: Chris Emblow Ecological Consultancy Services Ltd (EcoServe) 1 Marine ecology of the landfall and crossings - pre construction survey (June – July 2005) CONTENTS Contents .....................................................................................................................................2 List of tables...............................................................................................................................3 List of figures.............................................................................................................................3 Introduction................................................................................................................................4 Study area...............................................................................................................................4 Methodology..............................................................................................................................5 Intertidal sediment habitats ....................................................................................................5 Intertidal rock habitats............................................................................................................5 Subtidal sediment habitats......................................................................................................5 Subtidal video.........................................................................................................................6 Landfall ..................................................................................................................................6 Lower crossing point..............................................................................................................6 Upper crossing point ..............................................................................................................6 Results........................................................................................................................................8 Landfall ..................................................................................................................................8 Lower crossing point..............................................................................................................8 Upper crossing point ............................................................................................................10 Discussion................................................................................................................................11 Appendix 1 Maps showing sample station locations...............................................................12 Appendix 2 Locations and codes of sampling stations and transects ......................................14 Appendix 3 Infauna recorded from sediment sampling...........................................................16 Appendix 4 Granulometric results...........................................................................................19 Appendix 5 Fauna and flora recorded from quadrat studies....................................................22 Appendix 6 Plates ....................................................................................................................24 Appendix 7 Dúchas site synopsis ............................................................................................30 Ecological Consultancy Services Ltd (EcoServe) 2 Marine ecology of the landfall and crossings - pre construction survey (June – July 2005) LIST OF TABLES Table 1 Station locations, codes and descriptions ...................................................................14 Table 2 Fauna recorded from landfall transect ........................................................................16 Table 3 Fauna recorded from lower crossing (west) transect..................................................16 Table 4 Fauna recorded from lower crossing sublittoral transect............................................17 Table 5 Fauna recorded from upper crossing (north) transect.................................................17 Table 6 Fauna recorded from upper crossing (south) transect.................................................18 Table 7 Fauna recorded from upper crossing sublittoral .........................................................18 Table 8 Fauna, flora and substratum recorded from quadrats from the north shore transect .22 Table 9 Fauna, flora and substratum recorded from quadrats from the north shore control transect .....................................................................................................................................22 Table 10 Images of landfall and landfall control transect stations ..........................................24 Table 11 Images of lower crossing (west) and lower crossing (west) control transect stations ..................................................................................................................................................25 Table 12 Images of lower crossing (east) quadrat transect stations.........................................26 Table 13 Images of lower crossing (east) control quadrat transect stations ............................27 Table 14 Images of upper crossing (north) and upper crossing (north) control transect stations ..................................................................................................................................................28 Table 15 Images of upper crossing (south) and upper crossing (south) control transect stations ..................................................................................................................................................29 LIST OF FIGURES Figure 1 Site map of upper crossing sampling stations ...........................................................12 Figure 2 Site map of lower crossing sampling stations ...........................................................12 Figure 3 Site map of landfall sampling stations.......................................................................13 Figure 4 Landfall and landfall control transects ......................................................................19 Figure 5 Lower crossing (west) and lower crossing (west) control transects..........................19 Figure 6 Lower crossing sublittoral and lower crossing sublittoral control transects .............20 Figure 7 Upper crossing north and upper crossing north control transects .............................20 Figure 8 Upper crossing south and upper crossing south control transects.............................21 Figure 9 Upper crossing sublittoral and upper crossing sublittoral control transects..............21 Ecological Consultancy Services Ltd (EcoServe) 3 Marine ecology of the landfall and crossings - pre construction survey (June – July 2005) INTRODUCTION Ecological Consultancy Services Ltd (EcoServe) were asked by Shell E & P Ltd. to conduct a baseline environmental quality report on the areas around the proposed landfall and estuary crossing points related to the building of the gas pipeline in Co. Mayo. This report describes the methodology used during the collection of this data, and indicates the location of sample stations. The survey was designed to determine the effects, if any, on the marine ecology of Sruwaddacon Bay as a result of the building of the gas pipeline. Study area There were three main areas of study as follows: The landfall located on the beach just seaward of Sruwaddacon Bay, the lower crossing point in Sruwaddacon Bay just upstream of Rossport, and the upper crossing point towards the upper end of Sruwaddacon Bay. The work at the landfall was all intertidal, the upper and lower crossing points contained both intertidal and subtidal elements. Both sediment and rock habitats were surveyed. Ecological Consultancy Services Ltd (EcoServe) 4 Marine ecology of the landfall and crossings - pre construction survey (June – July 2005) METHODOLOGY The general survey methodology can be divided into intertidal sediment habitats, intertidal rock habitats, subtidal sediment habitats and subtidal video. First the general survey methodology is described, followed by the methodology applied to each section of the survey. Intertidal sediment habitats Quantitative core samples were taken in sediment habitats for the analysis of marine benthic infauna. Four combined replicates were taken per site using a 10.5 cm wide core inserted into the sediment to a depth of 20 cm. Sediment retained in the core was then passed through a 1mm mesh sieve. Any material retained on the sieve was then preserved in 70% Industrial Methylated Spirit (IMS) on site and returned to the laboratory for sorting and identification. A separate sample of the sediment was taken for granulometric and loss on ignition (LOI) analysis. These samples were delivered for analysis to an accredited laboratory unsieved and unpreserved. Where the habitat was unsuitable