Influence of an Offshore Mussel Aquaculture Site on the Distribution of Epibenthic Macrofauna in Îles de la Madeleine, Eastern Canada

Mussel farming influences benthic environments by organic loading and the addition of physical structure within aquaculture leases. This study evaluated near-field (distance to mussel structures, line-scale) bay-scale (inside vs. outside a blue mussel, Mytilius edulis , farm) effects an offshore farm in Îles de la Madeleine (Canada) on epibenthic macrofaunal communities. Benthic communities were underwater visual counts using SCUBA June July 2014. The influenced at line- bay-scales. Overall, crabs ( Cancer irroratus Pagarus pubecsens, acadianus ), sea stars Asterias rubens Northern moon snails Polinices heros American lobsters Homarus americanus ) more abundant sites than ocean quahogs Arctica islandica outside. No clear spatial trend was observed for winter flounder Pseudopleuronectes sand dollar Echinarachnius parma but both species differed (flounder) or showed differ (sand dollar) between sampling dates. Spatial distribution macrofauna evident lease as most directly below close lines anchor blocks. There no non-farm sites. Further investigation is needed evaluate if farms serve ecological traps that congregate them. long-term culture fitness remains unknown.