The effects of climate change and harmful human activity always seems to make their way to the top trending news. Recent studies warn that we are experiencing an accelerated mass extinction that could affect many living creature on this earth.
The waters are as affected by pollution as the air. Millions of fish are dying every year because of that.
Recent research proves that the nutritious pink salmon might be among the species affected by the high levels of acidity and gas in the water.
Two researchers from the zoology department of the University of British Columbia – Colin Brauner and Michelle Ou observed changes in young salmon fish behavior after rising the carbon dioxide level to the point water is estimated to have in the future, due to the effects of climate change.
They placed a small figurine in the tank and noticed that the salmon swam past it, proving it had lost its flight instinct that is so necessary when avoiding predators.
A fish would usually swim as far from the figurine as possible. But the contaminated water made it less active and it had the tendency to ignore what was going on around it.
This is extremely worrying because these fish need their survival instincts to stay alive. However, raised levels of carbon dioxide in the water seem to affect the “growth, metabolism, olfactory responses and anti-predator behavior in the early life stages,” the study said.
The loss of their senses does not only affect their ability to detect threat but also their instinct to return to the place of their birth. Salmon fish are extremely prolific and they tend to imprint on a the place where they were born. They come back to this place after migrating to other parts of the ocean to grow.
After two years of migration, they return to the same place to hatch their eggs.
“One of the ways they find their way back is when they are young they are able to recognize the different amino acid composition of that [home] river. So it’s kind of like the amino acid fingerprint of that stream,” said lead study author Michelle Ou.
She added that salmon use that particular fingerprint to get back home. However, because the contamination of the water affects their olfactory response, they might also become unable to smell the amino acids.
It is not yet certain what this means for the future of the salmon population because more research needs to be carried out in this respect, but it might have negative consequences on the fish populating the oceans. Nevertheless, the researchers said that there is the possibility for the fish to develop and adapt to the new conditions as well.
The results of the study were published in the journal Nature Climate Change and it stands as yet another scientific proof that pollution can have devastating effects on all the environments on the planet.
Image Source: techtimes