Introduction of species
Salmon farming in Chile is based on species such as coho salmon, Atlantic salmon (shown) and rainbow trout - all introduced from the Northern Hemisphere
Benefits of species introductions
While recent attention has focused on the adverse impacts of introduced species -- also known as alien species and alien genotypes -- species introductions are a valid means to improve production and economic benefit from fisheries and aquaculture.
Introduced species may have environmental as well as social and economic impacts. Aquatic ecosystems may be affected by the introduced species through predation, competition, mixing of exotic genes, habitat modification and the introduction of pathogens. Human communities may also be impacted through change in fishing patterns due to a newly-established fishery or through changes in land use and resource access when high valued species are introduced into an area.
Significant international instruments have recently been established to address the issue of species introductions, such as the Convention on Biological Diversity and the FAO Code of Conduct for Responsible Fisheries. These codes and conventions call for accurate assessments of the risks of using exotic species and are promoting the creation of information sources and an exchange of information on exotic species, their biological and ecological attributes, and potential impacts (both positive and negative). The problem is how to determine the impact of a proposed introduction into complex and dynamic aquatic ecosystems where our information base is often inadequate.