Managing the risks of sea lice transmission between salmon aquaculture and wild pink salmon fishery

A common external effect of aquaculture is the transmission of infectious diseases to wild fish stocks. A frequently cited example of this is the infection of wild salmon by sea lice from salmon farms. Management of the disease risk to wild salmon populations requires an understanding both of the disease transmission mechanisms and the control incentives faced by fish farmers. In this paper we develop a bioeconomic model that integrates sea lice population dynamics, fish population dynamics, aquaculture, and wild capture salmon fisheries. Using an optimal control framework, we investigate options for managing the sea lice infection externality. We pay particular attention to the role of sea lice management on the stability of wild stocks, and the sensitivity of sea lice effects on wild fisheries. We find that the stability of wild stocks is related to sea-lice-induced mortality (inversely) and the value of wild fishery.