SOTEAG Rocky Shore Monitoring Programme Annual Report Final
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Aquatic Survey and Monitoring Ltd. Tí Cara, Point Lane, Cosheston, Pembrokeshire, SA72 4UN, UK Tel office +44 (0) 1646 687946 Mobile 07879 497004 E-mail: [email protected] Survey of the rocky shores in the region of Sullom Voe, Shetland, July 2015 A report for SOTEAG Prepared by: Jon Moore & Christine Howson Status: Final st Date of Release: 1 December 2015 Recommended citation: Moore, J.J. and Howson, C.M. (2015). Survey of the rocky shores in the region of Sullom Voe, Shetland, July 2015. A report to SOTEAG from Aquatic Survey & Monitoring Ltd., Cosheston, Pembrokeshire. 33 pp + iii. Survey of the rocky shores in the region of Sullom Voe, Shetland, July 2015 Page i Acknowledgements Surveyors: Jon Moore, ASML, Cosheston, Pembrokeshire Christine Howson, ASML, Ormiston, East Lothian Other assistance and advice: Mr Alex Thomson and colleagues at BP Pollution Response Base, Sella Ness; Mr Simon Skinner, Port Safety Officer, Ports and Harbour Department, Sella Ness Report review: Christine Howson, ASML, Ormiston, East Lothian Dr Mike Burrows and other members of the SOTEAG monitoring committee Data access This report and the data herein are the property of the Sullom Voe Association (SVA) Ltd. and its agent the Shetland Oil Terminal Environmental Advisory Group (SOTEAG) and are not to be cited without the written agreement of SOTEAG. SOTEAG/SVA Ltd. will not be held liable for any losses incurred by any third party arising from their use of these data. © SOTEAG/SVA Ltd. 2015 Aquatic Survey & Monitoring Ltd. December 2015 Survey of the rocky shores in the region of Sullom Voe, Shetland, July 2015 Page ii Summary The potential environmental impacts of operations at the Sullom Voe oil terminal were recognised when construction of the complex began in 1975. A monitoring programme was devised by the Shetland Oil Terminal Environmental Advisory Group (SOTEAG). The rocky shore element of this monitoring programme began in 1976 and, apart from a break of two years (1982-83), the rocky shores in Sullom Voe have been surveyed annually. It is thought to be the longest running continuous programme of rocky shores surveys anywhere in the world. The programme was designed to assess gross changes in the plant and animal populations and the survey sites are centred on the oil terminal. Annual reports to SOTEAG have described the changes from year to year and assessed the effects of the terminal operation. This report summarises the work carried out in July 2015 – the 38th survey since the programme’s inception. The work was carried out using exactly the same methodology as that used since 1993. The surveys were carried out during a period of spring tides. The fifteen original transects in Sullom Voe and the five reference transects outside the Voe were re-surveyed, and the abundance of conspicuous species was recorded at five stations along each transect. A photographic record of each site was made. Comparisons of recorded abundances, field notes and photographs from the 2015 survey with those from the 2014 survey and previous surveys have been carried out. Rocky shore communities at the twenty sites in 2015 were generally very similar to 2014. The most notable features are listed below: Small numbers of the southern barnacle Chthamalus stellatus were recorded from three sites and small populations of the southern limpet Patella ulyssiponensis were recorded from two sites. Records of these species are still fairly new to this monitoring programme. Barnacle abundances remained high and observations suggest that survival of adults from the previous year was particularly high. Small populations of the immigrant barnacle Austrominius modestus still persist at sites within the inner Voe. Abundances of juvenile limpets were particularly high, almost reaching the peak recorded in 1997. The population of dogwhelks between the terminal jetties was still very small. Reduced densities were recorded from a number of sites. As discussed in previous reports, densities of rough periwinkles and flat periwinkles have remained relatively very low since 2000, while abundances of serrated wrack and bladder wrack have notably increased over the course of the monitoring programme. As also discussed in previous reports, the long term recovery of knotted wrack, Ascophyllum nodosum, at four sheltered sites in Sullom Voe, following various impacts in the 1970s, has been described and updated. Most of the changes summarised above are considered to be due to natural fluctuations, with the exception of the knotted wrack recovery. There was one reported oil spill (20 litres of marine diesel) in Sella Ness harbour in the period between the July 2014 and July 2015 surveys, with no observed impacts on the rocky shore communities. A containment bund between Jetties 1 and 2, following a seepage of oily waste from the terminal in 2012, is still in place, but remediation is planned. Analysis of the community data from the nearby rocky shore monitoring site still showed no apparent effects from the seepage or bund. Rocky shore communities around the Voe appeared to be in good condition and there were no detected effects of terminal activities at the transect sites. Aquatic Survey & Monitoring Ltd. December 2015 Survey of the rocky shores in the region of Sullom Voe, Shetland, July 2015 Page iii Contents Acknowledgements .................................................................................................................................. i Data access ............................................................................................................................................... i Summary ................................................................................................................................................. ii Contents ................................................................................................................................................ iii 1 Introduction ............................................................................................................................ 1 2 Methods ................................................................................................................................... 1 2.1 Field survey ............................................................................................................................... 1 2.1.1 Site and station location ............................................................................................................ 1 2.1.2 In situ species recording............................................................................................................ 3 2.1.3 Photography .............................................................................................................................. 3 2.2 Data analysis ............................................................................................................................. 3 3 Results ..................................................................................................................................... 7 3.1 Fluctuations in abundance of species ........................................................................................ 7 3.1.1 Hydroids .................................................................................................................................... 8 3.1.2 Chthamalus stellatus ................................................................................................................. 9 3.1.3 Semibalanus balanoides .......................................................................................................... 10 3.1.4 Austrominius modestus ........................................................................................................... 12 3.1.5 Small limpets & chitons .......................................................................................................... 13 3.1.6 Patella vulgata ......................................................................................................................... 14 3.1.7 Patella ulyssiponensis ............................................................................................................. 15 3.1.8 Littorina littorea ...................................................................................................................... 15 3.1.9 Littorina obtusata & L. mariae ................................................................................................ 17 3.1.10 Littorina saxatilis and Littorina saxatilis (ecotype neglecta) .................................................. 18 3.1.11 Nucella lapillus ....................................................................................................................... 20 3.1.12 Flustrellidra hispida & Alcyonidium spp. ............................................................................... 22 3.1.13 Red algal turf species .............................................................................................................. 22 3.1.14 Laminaria digitata ................................................................................................................... 25 3.1.15 Ascophyllum nodosum ........................................................................................................... 26 3.1.16 Fucus serratus ......................................................................................................................... 27 3.1.17 Fucus vesiculosus ..................................................................................................................