IMPACTS OF OFFSHORE WIND FARMS ON DIVERSITY OF DEMERSAL ASSEMBLAGES ON SANDBANKS OF THE WESTERN IRISH SEA

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1. IMPACTS OF OFFSHORE WIND FARMS ON DIVERSITY OF DEMERSAL ASSEMBLAGES ON SANDBANKS OF THE WESTERN IRISH SEA Javier Atalah; Julien Chopelet; Ilaria Coscia; Jennifer Coughlan; Edward Farrell; Jayne Fitch* MARine Biodiversity, Ecology and Evolution University College Dublin Gemma Byrne Geological Services Ireland MARBEE
2. Background • Europe wide carbon mitigation agreed under Kyoto protocol. • Renewable energy is a growing market. • Arklow Bank presently only offshore wind farm in Ireland, currently 7 turbines with plans to increase to 200.
3. Introduction • Sandbanks are important habitats, proposed Special Area of Conservation candidates. • Due to potential impacts through wind farms there is a need to have a comprehensive understanding of marine biodiversity.
4. Potential Impacts • Bird migration. • Cetaceans. • Artificial reef effect. • Alter of hydrodynamics. • Scouring and sedimentation. • Electromagnetic fields.
5. Aims 1. Characterise and compare community structure and biodiversity of benthic and demersal assemblages in sandbanks of the Western Irish Sea. 2. Assess potential impacts of offshore wind farms and cable route on biodiversity of benthic and demersal assemblages.
7. Study Sites
8. Statistical analyses • Analysis of variance (ANOVA) performed on Species Richness, Total Abundance and Shannon-Weiner Diversity Index. • Community structure was visualized using non-metric Multi Dimensional Scaling. • Community Structure as a whole were compared using Permanova. • PRIMER 6 + PERMANOVA
9. Results Only non-encrusting organisms were included in analysis, of these we identified 14,295 individuals in 98 taxa, in 5 Phyla. 0.74% 18.68% 5.53% 62.90% 12.14% Annelida Crustacea Mollusca Echinodermata Chordata
10. Species Richness Banks : p > 0.05 I vs C: p > 0.05 0 25 50 Kish Arklow Cable Blackwater Species richness +/- 1 SE
11. Total Abundance Banks : p > 0.05 I vs C: p > 0.05 0 6 12 Kish Arklow Cable Blackwater Log (Total abundance) +/- 1 SE
12. Shannon –Weiner Diversity Index Banks : p >0.05 I vs C: p = 0.0108 0 1 2 3 4 Kish Arklow Cable Blackwater Shannon +/- 1 SE
13. Community structure PERMANOVA I vs C: p > 0.05 Banks : p= 0.006
14. Characteristic Taxa Kish Arklow Cable Blackwater
15. Summary • The existing wind turbines and associated cable did not alter the abundance, species richness and structure of the demersal and benthic communities sampled. • There was an increase in Shannon-Weiner diversity at the cable site compared to the control. • At the spatial and temporal scale examined here, offshore wind farms were found to have little impact on fauna in this naturally highly disturbed environment.
16. Discussion • Close monitoring during future construction and operation of the proposed large scale installation is essential to identify any future impacts. • Conservation opportunities may exist to create marine reserves around offshore wind farms by introducing exclusion/no take zones.
17. Acknowledgements • Marine Institute for funding the research • Crew of the RV Celtic Voyager • Tasman Crowe and Stefano Mariani- UCD • Mathieu Cusson- University of Pisa • Cormac Nolan- UCD • Brendan O’Connor- BEC • Chris Frid- University of Liverpool • Jim Wilson- TCD • Brian O’Doherty- Airtricty and Alexis Billet- GE Energy References available upon request.