Chile: World Leaders in Salmon Farming

Chile is one of the largest marine aquaculture producers in the world. The country farms a variety of species but when it comes to salmon it is second only to Norway. This week we will focus on marine aquaculture in Chile to better understand conservation impacts in large scale salmon farms.

Chile

            “In 2007 salmon, mollusk and seaweed aquaculture production in Chile totaled 904 thousand tones making the nation the leading marine aquaculture producer in the western world (Buschmann et al. 2009).” One would think a large scale aquaculture operation as seen in Chile would be a pioneer for research concerning environmental impacts and regulation. Ironically, experts insist that the operation has been under very little scrutiny with regards to mitigating its impacts in the coastal region. According to Buschmann et al. 2009, evidence of limited regulation are clear through their licensing and monitoring procedures: farming sites have grown by over 50% since licensing and monitoring procedures were introduced in the 1990’s. As for scientific research, relevant information regarding farms in Chile, are lacking. In fact less than 4% of relevant papers published between 1988 and 2008 were related to Chile (Buschmann et al. 2009).

Do the shortcomings of scientific research and properly imposed regulations provide reason for concern? Of course they do! It is the quantity and diversity of the negative impacts posed by salmon farming which fuels this concern. Specific to Chile is the higher usage of antibiotic than in other countries. Antibiotics lead to a multitude of effects that appear present in multiple trophic levels. At higher levels antibiotics have been found in native fish near net pens and in pens especially, end up possibly modifying the resistance of benthic bacteria waste deposits (Cabello 2006; Miranda et al. 2002 as cited in Buschmann et al. 2009). With regards to chemicals copper precipitation has been found in sediments due to the usage of anti-fouling paints and un-eaten fish waste, leading to loss of benthic biodiversity (Buschmann and Fortt 2005 as cited in Buschmann et al. 2009). As we described in previous blog posts, diseases and parasites and reduction of wild stocks due to escapees (farm salmon) are factors which farms in Chile face and must regulate. (Refer to Figure 1)

Figure 1: The complex interaction between inorganic and organic wastes in the pelagic and benthic system surrounding aquaculture farms. (Source: Buschmann et al. 2009)

            Action must be taken to mitigate or at least decrease the effects of the inorganic and organic wastes that pose so many problems for the natural ecosystem. Many Integrated Multi-Trophic Aquaculture (IMTA) techniques have been incorporated around the world which Chile may benefit from. From this technique Atlantic Canada has discovered that growing seaweed and mussels in collaboration with Atlantic Salmon resulted in: enhanced growth of seaweed and mussels and decrease in organic and inorganic wastes due to absorption. (Chopin et al. 2004; Lander et al. 2004 as cited in Buschmann et al. 2009) Bacteria have been used as well to decrease wastes in some cases and various filter feeders. Such ideas exist and especially coastal studies could be applicable to that of the Chilean salmon farming. Nevertheless, Chilean companies have begun to invest in facilities that raise salmon smolts in closed land areas as opposed to lakes (Buschmann et al. 2009). Processes such as these serve to protect the natural populations of lakes by decreasing exposure to human influenced farm species. In Chile as well as globally much work such as ecological engineering (I.e. IMTA) must be performed to ensure all measures are being taken to provide suitable models for existing and potential aquaculture operations.


-Brandon and Mark

References:

Buschmann, A.H., Cabello F., Young, K., Carvajal, J., Varela, D.A., Henriquez L. 2009. Salmon aquaculture and coastal ecosystem health in Chile: Analysis of regulations, environmental impacts and bioremediation systems. Ocean & Coastal Management 52: 243–249

Chopin T, Bastarache S (2004). Mariculture in Canada: finfish, shellfish and seaweed.

World Aquaculture 35:37–41