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In 2010, more than 20 associations representing harvesters from five provinces bordering the range of American lobster (Homarus americanus) in Canada, from the Gulf of Maine to southern Labrador, joined government research scientists at Fisheries and Oceans Canada (and one provincial department) and researchers from Canadian universities (two English- and four French-speaking) to establish the Lobster Node. This partnership was formed to address knowledge gaps on lobster productivity, stock structure, and connectivity through collaborative research under the auspices of the Canadian Fisheries Research Network (CFRN), which was funded by the Natural Sciences and Engineering Research Council of Canada. In so doing, the research partners overcame barriers of geography, language, culture, education, and, in some cases, longstanding disputes around management and conservation measures. This paper reviews why and how the Lobster Node was formed, what it achieved scientifically, what benefits (and challenges) it provided to the partners, and why it succeeded. It concludes by advocating for the creation of a permanent collaborative platform to conduct research in support of lobster fisheries in Canada.

The presence of predators at soft-shell clam (Mya arenaria) culture sites is of great concern in Atlantic Canada. Laboratory studies were undertaken (i) to monitor the surface-exploration activity of the nemertean Cerebratulus lacteus to obtain a general indication of its activities throughout a 24-h period, and (ii) to describe its behaviour while feeding on M. arenaria to obtain a better understanding of the predation mechanisms involved. The first experiment showed that surface exploration varied significantly according to the presence or absence of prey. When clams were present, C. lacteus left its burrow at all times. In their absence, no predators were observed exploring the sediment surface between 21:00 and 03:00. Predator density also had an impact on surface-exploration activity. The second experiment showed that initial encounters between C. lacteus and its prey did not necessarily trigger proboscis eversion. Attacks with the proboscis, before consumption of the prey started, were concentrated in the siphon and foot areas. Cerebratulus lacteus introduced itself into the mantle cavity of M. arenaria through the same siphon and foot areas to feed. Our observations also revealed that C. lacteus may feed in a group on a single prey individual. The observations from this study provide preliminary and fundamental information for use in investigating adequate predator-control measures that may be useful for aquaculture.

We studied the effects of food intake, intraspecific density, and interactions between individuals on the growth of laboratory-raised juveniles of Nereis diversicolor fed different quantities of Tetramin. A daily intake of 3.33 mg of Tetramin per individual resulted in an optimal mean mass gain. At densities above 3000 individuals/m2, not only was the growth rate reduced, but biomass and survival rates were also diminished. Frequent handling and the thermodifferential shock that ensured created a stress that had the same negative effects. Variations in responses to aggregation or isolation were high, as revealed by groups of juveniles captured in winter or in spring reacting differently: growth was not affected by the breeding conditions in the winter-caught worms but was faster in spring-caught individuals kept in isolation.