Seaweed farming in Chaleurs Bay (Québec): results from 4 years of research and development activities.
There are currently 18 companies involved in seaweed harvesting, processing and sales in Quebec. There is also a growing interest from the mussel industry for diversification and several seaweed cultivation projects have been initiated with mussel producers. In 2006, one kelp harvesting company started a kelp farm in Chaleurs Bay and several experiments on Saccharina longicruris cultivation were carried out in the lab and on the farm. Through manipulation of photoperiod and water temperature, out of season sporogenesis was induced in S. longicruris blades kept in indoor basins. In vitro cultivation and multiplication of gametophytes allowed the seeding of culture ropes that were successfully out-planted on submerged longlines. In the kelp nursery, ropes seeded with spores currently yield 4 mm plantlets within 4 weeks and an experiment was carried out to determine optimal plantlet density. During the first attempts to cultivate kelp at sea, they were invaded by colonies of the non-indigenous bryozoa Membranipora membranacea, which resulted in the loss of most plants in the autumn. Modifying the culture schedule avoided bryozoan settlement on the kelp fronds. Efforts are now oriented towards increasing kelp culture yields and assessing new seaweed species such as Alaria esculenta and Palmaria palmata.