IWDG Comments on Kish Bank Exploration Well

26th Jan 2012 The Kish Bank and adjacent waters are important for cetaceans. Some of the highest densities of harbour porpoises recorded in coastal Irish waters have been recorded in the area in recent years (Berrow et al. 2008).

In addition sightings of bottlenose dolphins have increased dramatically in the area following the presence of a group of three individuals since August 2010. This small group seem to have taken up residency over the last two years, having been recorded every month. This would be only the third such group in Ireland after the Shannon Estuary (resident for many generations) and Cork Harbour (resident since February 2006, Ryan et al. 2010).

Given the importance of the area for these two species on Annex II of the EU Habitats Directive the IWDG would expect a much greater treatment of the potential effects of drilling on these species. We consider the potential effects could be caused by disturbance from increased traffic but more importantly due to noise generated from the drilling process.

Under 4.7.2 of the EIA, states that noise generated by drilling can be well above the ambient levels, but this has little effect on baleen whales. We would like the consultants to quantify or estimate the source levels and frequency bands expected during drilling and an exploration of the likely effects on odontocetes (especially harbour porpoise and bottlenose dolphin).

While there is considerable recent data on the effects of pile-driving and blasting and noise generated by wind turbines there is little published data on the intensity and effects of sound generated by drilling. However the consultants should provide expected sound pressure levels and attenuation curves, relevant to the substrate type.

While we welcome the provision of an MMO in the mitigation measures we feel more attention is required on sound pressure and other effects to inform the extent of permitted buffer zones and other relevant activities.

References

Berrow, S.D., Hickey, R., O'Brien, J. O'Connor, I. and McGrath, D. (2008) Habour Porpoise Survey 2008. Report to the National Parks and Wildlife Service. Irish Whale and Dolphin Group. pp.34.

Ryan, C., Rogan, E. and Cross, T. (2010) The use of Cork Harbour by bottlenose dolphins (Tursiops truncatus (Montagu)). Irish Naturalists' Journal 31(1), 1-9.