Open cage fish farms are a common sight on the west coast of British Columbia, Canada. On Vancouver Island, 29 of them are owned by a single company from Norway, where fish farms were first invented. As I mentioned in my post last August, there are a couple of major concerns with open cage fish farming.
The new concern is Infectious Salmon Anemia (ISA). Unlike mammals, the red blood cells of fish have DNA, and can become infected with viruses. The fish develop pale gills, and may swim close to the water surface, gulping for air. However, the disease can also develop without the fish showing any external signs of illness, the fish maintain a normal appetite, and then they suddenly die. The disease can progress slowly throughout an infected farm and, in the worst cases, death rates may approach 100%. This was the case last year in Chile, where virtually all of their farmed salmon had to be culled resulting in the layoff of over 20,000 workers.
Although this disease is believed to only affect Atlantic salmon, it’s affect on other fish species has yet to be determined.
Norway is the largest producer of farmed salmon and owns fish farms around the world, including 90% of the fish farms in British Columbia.
There is a really interesting video series which is shown in four parts. This is the second part. If you want to see the others, go to www.youtube.com/puresalmon.
Related posts:
The new farmed fish disease – ISA | Go Green http://bit.ly/d0cJhI #fish #agriculture #salmon