Farm-Raised Salmon Experience Depression, Science Says
New research is finding what leads to the phenomenon of “drop out” fish on salmon farms, or fish who float on the top of the water, seemingly having given up on life. A study from Royal Society Open Science suggests these fish are severely depressed. Not only do they exhibit behavior similar to what we know are depression symptoms in other animals, but the cortisol levels in these “drop out” salmon are sky high.
Marco Vindas, lead author of the study and biologist at Sweden’s University of Gothenburg, stated:
“I would not go so far as to say they are committing suicide, but physiologically speaking, they are on the edge of what they can tolerate, and since they remain in this environment, they end up dying because of their condition.”
Cortisol is a stress-response hormone regulated by the serotonergic system, which was found to be overactive in fish farms’ “drop out” salmon. We already have evidence pointing to mood problems in animals (including humans) who have disruptions in how the neurotransmitter serotonin is regulated. These findings support the theory that fish experience depression symptoms, which are likely tied to their environment.
Living in a fish farm is nothing like what living in the wild would be like for these creatures. Being confined in a space where aggression and competition for food runs rampant can only create a life filled with discomfort. Where the researchers fall short is taking these findings to their logical conclusion: we should stop farming fish. It’s that simple.
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