TY - RPRT
TI - Marine Mammals and Tidal Energy: Report to Scottish Government
AU - Hastie, G
AU - Evers, C
AU - Gillespie, D
AU - Irving, P
AU - Onoufriou, J
AU - Sparling, C
AB - The work presented under the Marine Renewable Energy (MRE) theme falls in to three tasks;MRE 1.1 – Fine scale marine mammal behaviour around tidal energy devices.MRE 1.2 – Harbour seal movement modelling.MRE 1.3 – Estimating collision risk using available information.This annual report only considers MRE 1.1 as MRE 1.2 and 1.3 have been completed and are available here: http://www.smru.st-andrews.ac.uk/reports/.MRE 1.1 This task aims to monitor the behaviour of marine mammals in the vicinity of an operational tidal turbine. A monitoring system utilising a combination of Passive Acoustic Monitoring (PAM), Active Acoustic Monitoring (AAM) and video cameras was deployed to identify marine mammal species using the areas around the turbine and to construct 3D tracks of their movements.The environmental monitoring system was successfully installed on the Turbine Support Structure (TSS) at Nigg on 3 October 2016 with deployment of the TSS at the site on 24 October 2016. Following the installation of the Atlantis Turbine in February 2017, initial commissioning of the monitoring system revealed a communications failure with all of the sensors. This was corrected during shore-based maintenance of the turbine in the summer of 2017.The Atlantis turbine was successfully re-deployed in mid-October 2017 and a second period of monitoring system commissioning was conducted. Power to the monitoring system turbine became available on 18 October and initial communications tests established that the PAM system was fully functional. However, no communications could be established with the video camera systems or the Gemini multibeam sonars. Plans to recover the platform with the sonars are currently being developed.Since commissioning, the PAM system has been operating stably for 95.7 % of the time. From the start of data collection up to the end of 31 December 2017 (~ ten weeks) a total of 11 dolphin and 199 porpoise encounters were made. This equates to a mean of 2.8 porpoise encounters and 0.2 dolphin encounters per day.A key output from the PAM data analyses will be the 3D locations of echolocation clicks in relation to the turbine. Echolocation click localisation techniques are currently being refined using the data collected. An important aspect of 3D localisation is to calibrate the array by pinging it with a sound source from a known location; trials to do this are being planned and will be used to improve localisation accuracy.To examine fine scale movement of seals in a wider spatial context, 24 harbour seals were caught and tagged in the Inner Sound during two field efforts between 26 September and 3 October 2016, and between 2 and 13 April 2017. These data aim to provide real time locations of seals to base stations on shore each time a seal surfaces, providing supporting evidence to determine if a collision occurs between a seal and a turbine.In total 115,100 locations were recorded from the tagged seals during the two tagging deployments. Seals spent a total of 16 % of their time in the Inner Sound, with a relatively low number of locations (195) recorded within the MeyGen lease area. Only three seals were recorded at the surface within 100 m of any of the turbines; the closest surface location to any of the turbines was 35.15 m.
DA - 2018/01//
PY - 2018
SP - 21
PB - Sea Mammal Research Unit (SMRU)
LA - English
KW - Marine Energy
KW - Tidal
KW - Collision
KW - Marine Mammals
KW - Pinnipeds
ER -