Journal of Marine Biology and Aquaculture

The bivalve aquaculture industry has become an important socio-economic component of many coastal communities throughout the world and marine molluscs presently account for 60% of global marine aquaculture production[1]. Largely cultivated on the east of Canada (over 20,000 tons per year), the mussel industry represents an annual market of around $30 million[2]. Wild seed collection remains a critical activity for the bivalve aquaculture industry. In Eastern Canada, the availability of mussel seeds is not a concern from a quantitative standpoint, however, it has potential limitations from a qualitative stand[3]. Populations of the blue mussel, Mytilus edulis and the bay mussel, M. trossulus coexist in the Gulf of St. Lawrence, Scotian Shelf and Gulf of Maine. Along the Atlantic coast of North America, M. edulis extends from Newfoundland and Labrador (Canada) to North Carolina (USA), while M. trossulus is restricted to sub-polar areas with a southern distribution limit in the Gulf of Maine[4-7]. In these areas, the frequency of hybridization between these two species of the Mytilus complex is low and generally < 10%[4,8-10], suggesting that the process of hybridization seem limited in this region[11]. The mussel aquaculture industry in Atlantic Canada is significantly influenced by genotype-dependent growth variation in areas where seeds collection of both M. trossulus and M. edulis occurs[12]. Thus, the presence of these two species could have a significant impact on the productivity of a mussel farm[13,14]. M. edulis is generally considered to outperform M. trossulus, by their higher growth rate[12,15] and their thicker and stronger shell[16] less susceptible to shell breakage during primary processing[13,17]. 1Institute of Ocean Sciences, University of Quebec at Rimouski, 310 allée des Ursulines, Rimouski, Quebec, Canada 2Department of Fisheries and Oceans, Aquaculture and Coastal Ecosystem Section, Gulf Fisheries Centre, Moncton, NB, Canada