Interactions Between
Finfish Aquaculture and
Lobster Catches Studied
Canadian scientists investigated interactions between open-net pen finfish aquaculture and lobster catches in a sheltered bay in Nova Scotia, Canada. They used fishermen’s participatory research in annual lobster trap surveys over seven years. Fishermen recorded lobster catches during the last two weeks of May from 2007 to 2013. Catches for each trap haul were recorded separately for egg bearing and market-sized lobsters. Catch trends within the bay were compared to regional trends. Results of correlation analyses indicated that egg bearing catch trends were strongly affected by the fish farm’s feeding/fallow periods. There was no significant correlation between trends for bay and LFA lobster landings.
Patterns of lobster catch per unit effort extending over considerable distance in Port Mouton Bay appear to be influenced by proximity to the fish farm regardless of year-to-year variation in water temperatures and weather conditions. The research showed that odors and habitat changes surrounding open-net pen finfish operations are potential factors affecting lobster displacement.
Along with the increase in lobster landings has been the rise of open net pen finfish aquaculture in eastern Canada. These operations are largely, but not exclusively, located in sheltered areas of the coastal zone which provide protection from heavy seas, suitable year-round temperatures and, depending on location, some tidal flushing (Milewski, 2001). The number of fish stocked per farm site can range from 200,000 to 700,000 depending on the farm production plan.
