Evaluation of risk mitigation measures for the introduction of invasive alga in order to facilitate requests for mussel and scallop spat transfers

Description

The mussel farming industry in eastern Canada is largely based on the collection of spat in areas suitable for the settlement of larvae and transfer to growing sites until a harvestable size is attained. In eastern Quebec (Gaspé region), this was typically done on a small scale (a few kilometres). In recent years, however, there have been several failures in collecting spat in the Gaspé Peninsula, forcing a number of mussel farmers to apply for transfers to a site on the south shore or Chaleur Bay, near Miscou, NB. However, this area is known to be contaminated by the invasive green alga Codium fragile ssp. As a result, spat transfers cannot be authorized by the Introductions and Transfer Committee because this invasive alga has not yet been listed in the Gaspé Peninsula, which affects shellfish growers' production. This potential loss of production is a major concern for the industry at this time. The project will assess the effectiveness of various treatments at different stages in the Codium life cycle likely to be associated with mussel spat and prioritizing its survival. The results would ensure that decisions are made on transfers and introductions based on scientific facts. The study could also potentially result in new ways of treating other aquatic invasive species (AIS) while prioritizing treatments already known to be effective against other invaders in the Maritimes. It would also be interesting to verify the effectiveness of these procedures on sea scallops (Placopecten magellanicus), a species also targeted by transfers between the Magdalen Islands and the Gaspé Peninsula. Codium was recently found in the Havre-aux-Maisons lagoon on the Magdalen Islands and this limits transfers from this area.

Program Name

Aquaculture Collaborative Research and Development Program (ACRDP)

Year(s)

2010 to 2012

Ecoregion(s)

Atlantic: Gulf of St. Lawrence, St. Lawrence Estuary

Principal Investigator(s)

Chris McKindsey
Email: Chris.Mckindsey@dfo-mpo.gc.ca