88c1ac86-1ce3-41cf-8c16-851cc6043375 eng series The Crown Estate +44 020 7851 5000 16 New Burlington Place London W1S 2HX United Kingdom enquiries@thecrownestate.co.uk http://www.thecrownestate.co.uk pointOfContact 2015-11-02 MEDIN Discovery Profile 2.3.8 EPSG: 4326 2006-2010, SMRU Ltd., SeaGen Strangford Lough, Using Telemetry to Investigate the Effect of SeaGen on Harbour Seal Behaviour and Movement 2010-11-05 publication SL_14 One of the principal environmental concerns about tidal turbines is the potential for injurious collision with marine animals. Until recently there has been little opportunity to collect and analyse data to assess this risk. Three separate deployments of GPS tags on harbour seals in Strangford Lough and Narrows during the development of the SeaGen tidal turbine have provided the first opportunity to measure individual seal behaviour in relation to the presence and operation of a commercial scale tidal turbine. Thirty six seals were tagged over three years, in 2006 (pre-installation), 2008 (during installation) and 2010 (operation). There was no overall difference in the rate at which seals travelled up and down the narrows past the location of the turbine between the three deployments. However these average rates had wide confidence limits as a result of a wide degree of variation in the behaviour of individual seals. This uncertainty limited the use of this data for investigating differences between years. In 2010, when the turbine was operational, there was evidence that the rate at which seals transited the Narrows reduced when the turbine was on, relative to when it was off. The biological importance of this reduction is unknown at present. Over all three years the frequency of transits was higher at slack tide than when the current was running. Although visual inspection of the distribution of locations where seals chose to transit the narrows suggested local avoidance of the turbine site in 2010, high inter-individual variability limited our ability to detect any significant difference. Examining the rate of transits which were close to the turbine (<25m) when it was operating gives an average rate for each seal of 3 transits per year. Scaling up to the total population suggested that 300 such transits may have occurred during the period between April and August. There were 210 emergency shut downs during this same period. The results of this study suggest that the operation of the turbine is affecting the transit behaviour of seals in the narrows and therefore the risk of seals colliding with an operational tidal turbine may be lower than would be estimated by assuming no avoidance and a spatial and temporal uniform density of animals. This series contains the survey report. Marine Current Turbines Limited +44 (0)117 926 9906 St Brandon's House, 27-29 Great George Street, Bristol BS1 5QT http://www.marineturbines.com/ custodian SMRU Ltd 01334 463446 5, Atholl Crescent Edinburgh EH3 8EJ smru@st-andrews.ac.uk http://www.smru.st-andrews.ac.uk/ originator notPlanned .pdf Renewable Energy Lease area The Crown Estate Renewable Energy Development Areas 2012-05-15 revision 1 Pre-Construction monitoring Construction monitoring Post-Construction monitoring The Crown Estate Renewable Energy Development Phases 2012-05-15 revision 1 Seal behaviour SeaDataNet Parameter Discovery Vocabulary 2015-09-09 revision 89 gps Marisaurus Thesaurus 2010-09-22 revision 28 Taggings SeaDataNet Cruise Summary Report data categories 2011-12-09 revision 3 Seal abundance SeaDataNet Parameter Discovery Vocabulary 2016-02-17 revision 91 Marine Mammals Global Change Master Directory Science Keyword variables 2007-04-18 revision 4 Marine Environmental Data and Information Network Marine Environmental Data and Information Network http://marinedataexchange.co.uk/pages/terms-of-use.aspx copyright otherRestrictions copyright otherRestrictions http://marinedataexchange.co.uk/pages/terms-of-use. http://marinedataexchange.co.uk/pages/terms-of-use.aspx eng biota environment oceans -5.613444 -5.493281 54.306874 54.402910 2006 2010 http://www.marinedataexchange.co.uk/search?q=#fq=fq%3DProject%253Amde3dsl8633 download https://www.marinedataexchange.co.uk/details/1927/summary A link to the web service or dataset. https://www.marinedataexchange.co.uk A link to the general host site. series Metadata generated by The Crown Estate for the purpose of publishing on the Marine Data Exchange.