
Pink salmon spawning
A recent study suggests that the population of pink salmon around the world is seriously threatened by the devastating impact of climate change and global warming. The researchers who conducted the study found that carbon dioxide is responsible for the acidification of the freshwater systems, which directly affects the fish population.
The new research was conducted by scientists from the University of British Columbia who analyzed pink salmon for about ten weeks. The researchers examined the fish from the egg stage until they migrated into the ocean. The fish were divided into two groups: the first group was kept in water similar to what is found in the wild in the present, while the second group was kept in freshwaters that had a level of carbon dioxide similar to what the scientists assume it would be 100 years from now.
According to the study’s results, the pink salmon group that was raised in waters with a higher level of acidity was not able to sense the surrounding as well as the other group. The ability of smelling the surround is crucial for the fish to find their food and stay away from predators. The journeys taken by the pink salmon, famous for swimming back to their home for mating, could be seriously affected if the pH level of the water continues to drop.
Although there are numerous studies that show the dangers of ocean acidification, not much is known about the impact of acidification on smaller waters, such as rivers, lakes or ponds.
Colin Brauner, a researcher at the University of British Columbia, explained that most of the studies are about the increasing levels of acid in the oceans, yet more than 40% of the world’s fish species live in freshwater. Brauner added that researchers need to learn more about how CO2 is affecting the freshwater fish species. He said the recent study shows how carbon dioxide affects the pink salmon population and how it can impact the fish’s ability to survive and return to their mating homes.
According to Brauner, the study also revealed that a higher level of acidification can affect the pink salmon’s ability to use oxygen while it undergoes physical effort. This can disable them to escape from predators, the researchers fear.
Michelle Ou, the study’s lead author, said that because the water’s levels of CO2 are not that high at the moment, he wasn’t expecting to have such a big impact on the pink salmon’s physiology, growth and general behavior, but the study reveals some alarming facts.
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