Impacts of Salmon Aquaculture on the Coastal Environment: A Review

• Main Author: Inka Milewski
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Atlantic salmon
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.180.6495; http://www.agobservatory.org/library.cfm?refID=70188

By the end of this decade, world-wide production of farmed salmon is estimated to reach 2,000,000 mt and almost all farmed salmon production takes place in sheltered areas of the coastal zone. This paper reviews the main activities associated with the marine phase of salmon aquaculture production, the pathways to the environment of the various activities and the potential effects on the coastal environment. The review is based on a extensive survey of the last ten years of published scientific research. It concludes there are large gaps in our knowledge of the impacts salmon aquaculture has on the marine environment. At the same time, the review reveals that salmon aquaculture: 1) contributes to coastal nutrient pollution, exacerbating existing problems from agricultural runoff, sewage discharges and atmospheric deposition; 2) releases toxic compounds, exacerbating existing pollution of coastal ecosystems; and 3) interferes with the performance of existing wild salmonid stocks, exacerbating the continuing decline in wild Atlantic salmon stocks. Given the large gaps in our knowledge and the universally acknowledged poor state of health of estuaries and coastal waters, it is recommended that regulatory agencies and policy-makers apply the precautionary principle to decisions concerning expansion of salmon, as well as other finfish, aquaculture in coastal waters and to maximizing mitigative measures (e.g., closed containment systems, restrictions on the use of pesticide and acoustic deterrent devices, moratoriums, and comprehensive environmental assessments) on existing operations.