The rise of fish farms has resulted in a rise in fish viruses. The most recent is the marine viral disease, Infectious Salmon Anaemia (ISA).
Salmon that have this disease can be detected as they have pale gils. They often swim towards the surface and gasp for air. However, any fish show no signs of illness other than sudden death.
Outbreaks were first detected in Norway in 1984 and have since spread to British Columbia, Chile and Scotland.
What is concerning to many anglers is that these diseases are spreading to fish outside of fish farms. As such, be careful of where you are fishing and the location of fish farms. And inspect the fish after catching them. If you catch any fish suspected of having a disease, contact your local fish department or ministry.
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