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BACI monitoring of effects of hydraulic dredging for cockles on intertidal benthic habitats of Dundalk Bay, Ireland

Published online by Cambridge University Press:  16 June 2014

Sarah Clarke*
Affiliation:
Marine Institute, Rinville, Oranmore, County Galway, Ireland
Oliver Tully
Affiliation:
Marine Institute, Rinville, Oranmore, County Galway, Ireland
*
Correspondence should be addressed to: S. Clarke, Marine Institute, Rinville, Oranmore, Co. Galway, Ireland email: sarah.clarke@marine.ie

Abstract

Hydraulic dredging for bivalves, such as cockles (Cerastoderma edule), has the potential to cause significant impacts on marine intertidal benthos. Although this fishing activity is common in northern European Natura 2000 sites such impacts may be incompatible with conservation objectives for designated habitats and species within these sites. In 2009–2010 a spatially nested control-impact study was undertaken before (t0), 8–9 days after (t1) and 4 months (t2) following dredging and extraction of 108 tonnes of cockles from a standing stock of 2158 tonnes in Dundalk Bay. This study failed to detect significant effects on benthic sediments, or the overall community structure. However, a fishing effect on the target species C. edule in one sampling area and a short lived effect on the bivalve Angulus tenuis were identified. Significant spatial and temporal variability in abundance of species and taxonomic groups, unrelated to fishing effects, was observed. Previous studies on the effects of fisheries on marine intertidal benthos have reported variable results, related to study design and objectives and the physical characteristics of the study site. Site specific studies, relative to the intensity and frequency of proposed fishing activity, may be required to adequately inform managers whether such activities are compatible with specific conservation objectives for Natura 2000 sites.

Type
Research Article
Copyright
Copyright © Marine Biological Association of the United Kingdom 2014 

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References

REFERENCES

ABPmer (2013a) Tools for Appropriate Assessment of Fishing and Aquaculture Activities in Marine and Coastal Natura 2002 Sites. Report II: Intertidal and Subtidal Sands. Report R. 2070. ABP Marine Environmental Research Ltd, Southampton.Google Scholar
ABPmer (2013b) Tools for Appropriate Assessment of Fishing and Aquaculture Activities in Marine and Coastal Natura 2002 Sites. Report III: Intertidal and Subtidal Muddy Sands and Sandy Muds. Report R. 2071. ABP Marine Environmental Research Ltd, Southampton.Google Scholar
ASU (2009) A survey of mudflats and sandflats in Ireland. An intertidal soft sediment survey of Dundalk Bay. A report to the National Parks and Wildlife Service, Dublin, 21 pp.Google Scholar
Bell, C.M. and Walker, P. (2005) Desk study to assess the impact of cockle suction dredging on The Wash and North Norfolk Coast European Marine Site. English Nature Research Reports, No 670.Google Scholar
Clarke, K.R. and Gorley, R.N. (2006) PRIMER v6: user manual/tutorial. Plymouth: PRIMER-E.Google Scholar
Crowe, O. (2005) Ireland's wetlands and their waterbirds: status and distribution. Newcastle, County Wicklow: Birdwatch Ireland.Google Scholar
Ens, B.J., Smaal, A.C. and deVlas, J. (2004) The effects of shellfish fishery on the ecosystems of the Dutch Wadden Sea and Oosterschelde. Final report on the second phase of the scientific evaluation of the Dutch shellfish fishery policy (EVA II). Alterra, The Netherlands.Google Scholar
Fahy, E., Carroll, J. and Murran, J. (2005) The Dundalk cockle (Cerastoderma edule) fishery in 2003–2004. Irish Fisheries Investigations Series B, Marine Institute, Ireland, no. 14, 20 pp.Google Scholar
Ferns, P.N., Rostron, D.M. and Siman, H.Y. (2000) Effects of mechanical cockle harvesting on intertidal communities. Journal of Applied Ecology 37, 464474.CrossRefGoogle Scholar
Goss-Custard, J.D., Stillman, R.A., West, A.D., Caldow, R.W.G., Triplet, P., le V dit Durell, S.E.A. and McGrorty, S. (2004) When enough is not enough: shorebirds and shellfishing. Proceedings of the Royal Society of London, B 271, 233237.CrossRefGoogle ScholarPubMed
Hall, S.J. (1994) Physical disturbance and marine benthic communities: life in unconsolidated sediments. Oceanography and Marine Biology: an Annual Review 32, 179239.Google Scholar
Hall, S.J. and Harding, M.J.C. (1997) Physical disturbance and marine benthic communities: the effects of mechanical harvesting of cockles on non-target benthic fauna. Journal of Applied Ecology 34, 497517.CrossRefGoogle Scholar
Hervas, A., Tully, O., Hickey, J., O'Keeffe, E. and Kelly, E. (2008) Assessment monitoring and management of the Dundalk Bay and Waterford Estuary cockle (Cerastoderma edule) fisheries in 2007. BIM, Fisheries Resource Series, 7/2008, 38 pp.Google Scholar
Hiddink, J.G. (2003) Effects of suction-dredging for cockles on non-target fauna in the Wadden Sea. Journal of Sea Research 50, 315323.CrossRefGoogle Scholar
Hurlbert, S.H. (1984) Pseudoreplication and the design of ecological field experiments. Ecological Monographs 54, 187211.CrossRefGoogle Scholar
Kaiser, M.J., Broad, G. and Hall, S.J. (2001) Disturbance of intertidal soft-sediment benthic communities by cockle hand raking. Journal of Sea Research 45, 119130.CrossRefGoogle Scholar
Kraan, C., Piersma, T., Dekinga, A., Koolhaas, A. and van der Meer, J. (2007) Dredging for edible cockles (Cerastoderma edule) on intertidal flats: short term consequences of fisher patch-choice decisions for target and non-target benthic fauna. International Council for the Exploration of the Sea Journal of Marine Science 64, 17351742.Google Scholar
Marine Institute (2011) Shellfish stocks and fisheries review. The Marine Institute, Rinville, Oranmore, Galway, Ireland and BIM, Crofton Road, DunLaoghaire County Dublin, Ireland, 64 pp.Google Scholar
NPWS (2011a) Conservation objectives for Dundalk Bay SAC 000455 and Dundalk Bay SPA 004026. Dublin: National Parks and Wildlife Service, Version 1.0, 35 pp.Google Scholar
NPWS (2011b) Dundalk Bay SAC. Site code 455. Conservation objectives supporting document—marine habitats. Dublin: National Parks and Wildlife Service, Version 1.0, 11 pp.Google Scholar
Perkins, E.J. (1988) The impact of suction dredging upon the population of cockles in Auchencairn Bay, (1988). Peterborough: Nature Conservancy Council, South West Scotland Region, no. NC232 I.Google Scholar
Peterman, R.M. (1990) Statistical power analysis can improve fisheries research and management. Canadian Journal of Fisheries and Aquatic Sciences 47, 215.CrossRefGoogle Scholar
Piersma, T., Koolhas, A., Dekinga, A., Beukema, J.J., Dekker, R. and Essink, K. (2001) Long-term indirect effects of mechanical cockle-dredging on intertidal bivalve stocks in the Wadden Sea. Journal of Applied Ecology 38, 976990.CrossRefGoogle Scholar
R Development Core Team (2010) R: a language and environment for statistical computing. Vienna: R Foundation for Statistical Computing.Google Scholar
Queirós, A.M., Hiddink, J.G., Kaiser, M.J. and Hinz, H. (2006) Effects of chronic bottom trawling disturbance on benthic biomass, production and size spectra in different habitats. Journal of Experimental Marine Biology and Ecology 335, 91103.CrossRefGoogle Scholar
Stewart-Oaten, A., Murdoch, W.M. and Parker, K.R. (1986) Environmental impact assessment: “Pseudoreplication” in time? Ecology 67, 929940.CrossRefGoogle Scholar
Tebble, N. (1976) British bivalve seashells a handbook for identification. Oxford: Alden Press, 213 pp.Google Scholar
Underwood, A.J. (1994) On beyond BACI: Sampling designs that might reliably detect environmental disturbances. Ecological Applications 4, 415.CrossRefGoogle Scholar
West, A., McGrorty, S., Goss-Custard, J., Sanderson, W. and Gray, C. (2004) Modelling shorebirds and their food on the Dee Estuary, Traeth Lafan and Burry Inlet SPAs to inform target setting and site management—phase 2. In A report to the Countryside Council of Wales from the Centre for Ecology and Hydrology. CCW Marine Monitoring Report No. 19, 151 pp.Google Scholar
Wijnhoven, S., Escaravage, V., Herman, P.M.J., Smaal, A.C. and Hummel, H. (2011) Short and mid-long term effects of cockle-dredging on non-target macrobenthic species: a before-after-control-impact experiment on a tidal mudflat in the Oosterschelde (The Netherlands). Marine Ecology 32 (Supplement 1), 117129.CrossRefGoogle Scholar