Start date

1 September 2008

End date

28 February 2011

Measuring the effects of suspended particulate matter and smothering on the behaviour, growth and survival of key species found in areas associated with aggregate dredging

Reference:
08/P76
Organisation:
Scottish Association for Marine Science (with PDRA)
Amount Funded:
£139,884
Status:
Current

Many benthic aquatic organisms rely on the suspension of particulate matter for food and / or for building materials, yet the water currents and associated sediment dynamics which provide the ideal environment for these animals can be disrupted by anthropogenic processes. Aggregate dredging and associated screening, for example, generate significant amounts of suspended particulate material (SPM) which can result in smothering of habitats and / or an alteration of the SPM composition which supplies those habitats. Using specially designed aquaria SPM conditions typical of dredging activities can be simulated allowing us to measure changes in behaviour, growth and survival of key benthic species commonly found within the sphere of influence of marine dredging sites, specifically: the Ross worm (Sabellaria spinulosa); mussel (Mytilus edulis); scallop (Pecten maximus) and brown crab (Cancer pagurus). Additionally smothering tolerances will be determined for the edible sea urchin (Echinus esculentus), common brittle star (Ophiothrix fragilis), the sea anemone (Sagartiogeton laceratus) and sea squirt (Ciona intestinalis). These data can then be used to inform mitigation measures for the sustainable extraction of aggregates and may also be fed into environmental impact models that allow predictions of cumulative impact of dredging activities.