The West Coast is home to a huge population of Juvenile pink salmon. However, according to a new study released by UBC these humble fish are now struggling to survive, battling at two fronts: greenhouse gas emissions and increasing acidification of rivers.
An international study in 2013 said acidification of the oceans has been happening at the fastest pace for 55 million years, because of rising human greenhouse gas emissions.
The fish form the most abundant type in the Pacific, but they rely on their sense of smell to detect danger and increasing acid levels have not only slowed down their early growth, but also made them more susceptible to attack by larger predators.
The study claims that Chinook salmon could be wiped out by 2100.
When experiments were conducted in Canada, pink salmon grew on average to only about 32 mm after 10 weeks, when raised in waters with roughly double current carbon dioxide concentrations, as expected in 100 years.
That was shorter than the 34 mm in waters with current levels. The young fish also weighed less and had a poor sense of smell.
Furthermore, damage done by acidification “in fresh water in pink salmon could occur in all other salmonids”, Colin Brauner, a co-author at the University of British Columbia, told Reuters.
Brauner said it was too early to say if the disruptions would last into adulthood and mean smaller commercial catches.
Carbon dioxide, is the central greenhouse gas responsible. It readily reacts with water to produce a weak carbonic acid – this is particularly harmful to creatures ranging from oysters to lobsters which find it harder to build protective shells.
In the past, the impacts of rising carbon dioxide levels have been studied in the seas more than in fresh water, yet 40 per cent of all fish are freshwater, said Brauner.
It remains to be seen how salmon, and other marine life adapt to increasing carbon dioxide levels around them.