Till the last hope: The ISA virus, the salmon industry and Patagonia

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At least 70 percent of the Chilean salmon industry is found in the Los Lagos region, but due to the contamination its left behind, companies are migrating further south into Patagonia.
By Hector Kol
Editors Note: The following is from Issue 1. 
Salmon exports in Chile began in 1984. The industry experienced steady growth and with it, salmon cages in Chilean waters multiplied fast.  Two decades later, Chile became the second largest producer of salmon in the world.  Nothing seemed capable of slowing this booming industry. 
Today, the industry’s thousands of cages remain afloat in the sea but are now empty.  Over the past three years, salmon have been dying by the tens of thousands leaving severely wounded the industry, its workers and the environment. Who is responsible?  In part, the answer is the ISA (infectious salmon anemia) virus. But the inability of the government to prevent the introduction into our marine ecosystem some salmon eggs infected with a variety of diseases must also take its share of rebuke.
The arrival of the virus
In June 2008, the Magallanes office of the National Fisheries Service (SERNAPESCA) announced it had detected the ISA virus in two samples of reproductive salmon from the Caleta Delano facility of the Norwegian-owned Marine Harvest company, located just north of the town of Puerto Natales. 
This case constituted the first detection of the ISA virus in Magallanes, but it also signaled the failure of bio-security measures taken by SERNAPESCA and the companies to avoid propagation of this deadly disease.  With this detection, in less than a year, the disease had appeared 2,200 kilometers to the south of its apparent origin in the Chauques Islands of the Los Lagos region.
Neither SERNAPESCA nor the salmon industry know exactly when or how the disease entered the country.  When they announced the presence of the ISA virus in Caleta Delano, SERNAPESCA declared that Marine Harvest’s salmon had entered Magallanes contaminated in 2006.  Then, a day later, the regional head of the Aquaculture Unit of SERNAPESCA, Alicia Gallardo, stated that these salmon had actually entered the area infected as far back as 2005.  Meantime, in response to these allegations from the government, Marine Harvest maintained the fish had entered their facility healthy but that somehow became infected on site. 
The origin of the disease remains unknown in Chile. It has been stated by some, principally by SERNAPESCA, that there is no vertical transmission of this virus, from parents to offspring.  But in 2007 scientific evidence arising from outbreaks of the disease in Norway do confirm there is a vertical transmission of the disease. 
Salmon in Chile are an introduced species that are farmed from eggs. In salmon farms, only eggs, and not grown fish, are cultivated. The evidence is thus strikingly clear that it’s the imported eggs which are the origins of the disease: in Chile, there is no other possibility of transmission, neither the presence of the pathogen on the surface of cells or intercellular. 
Recent declarations by Victor Hugo Puchi, owner of Aqua Chile, the largest Chilean-owned salmon company, are totally correct in asserting that “Chile cannot continue to import diseases.” His opinion is backed up by scientist Sandra Bravo of Austral University, who in a recent seminar stated that 70 percent of the salmon eggs that are imported are invalid for the development of smolts, or young fish, as a result of diseases carried from their distinctive origins. 
Photo: Francisco NegroniPhoto: Francisco Negroni
A majority of experts in Chile do agree, however, that the arrival and spread of the virus in Chile was due to lack of sanitary control.  Diseases in farmed fish are transmitted when the fish are stressed and, in particular, when the cages are too close to each other. In such sites, there is often an excessive, overpopulation of fish. In its recent heyday, the Chilean salmon industry produced up to 40 kilograms of salmon per cubic meter of water, which stands in stark contrast to the SERNAPESCA-recommended limit of 15 kilograms (a figure which the majority of the companies declared in their environmental permits). 
Chile is not prepared to regulate intensive salmon farming. For two decades, sites have been occupied for fish farm cages without knowing the capacity of the aquatic environment to absorb, recycle and decompose the thousands of tons of organic material generated by salmon centers every year. This also includes unknown quantities of chemical products that are used without limit or regulation.
Today, the majority of the coastline in salmon farming areas is contaminated chemically and biologically: the studies of load capacity should have been done before installing the cages, not afterwards. 
Migration toward Patagonia?
Now, the problem is going further south. A world-renowned touristic zone such as Puerto Natales, with more than 100,000 visitors annually, at present must have its Ultima Esperanza Bay declared a “vigilance zone” for the virus. Under this designation, the region’s fjords fed by glaciers, where tourists go for pristine landscapes, can currently only be visited, theoretically, after disinfection for products deemed toxic to the marine environment, which is required by SERNAPESCA in order to avoid a new spread of a virus. 
In the Aysen region, fishing and environmental authorities have already approved the installation of 300 salmon farming centers. There are 500 centers authorized in the Magallanes region. Another 3,000 salmon farming centers are on the waiting list in Aysen and Magallanes.  All of this without any requirement for environmental impact studies nor the most minimal sanitary measures to prevent the ISA virus from expanding into a region that is prized by people the world over.   
Fishermen, local business leaders, students and citizen organizations in Puerto Natales have formed “Patagonia Without Salmon Farms,” a citizens group which is pressuring the government to establish a moratorium on salmon farming in Magallanes and a quarantine on salmon centers already in the Ultima Esperanza Bay. 
Tourism is an economic sector with tremendous growth potential for Patagonia, especially ecotourism.  Governments have praised and defended it because it leaves income, creates jobs and benefits all sectors of the population.  Magallanes and Aysen are a faithful reflection of this tendency, eco-tourists from around the globe visit every year to enjoy its scenic beauty. Here, tourism and environmental protection must be priority when considering any salmon farming expansion. 
Hector Kol is a Chilean marine biologist working on salmon farming issues in the country for more than two decades.