CLAS: Colby Liberal Arts Symposium

How Ocean Acidification May Impact our Fisheries

Parker-Reed, SSWAC

Of all the effects of anthropogenic CO2 production, the absorption of carbon into our oceans and the resulting acidification has the potential to be the most detrimental impact on the ocean ecosystems. As we release more CO2 into the atmosphere, it is absorbed into the ocean where it reacts with water and carbonate ions (CO3^2-) to form bicarbonate (HCO3^-). This poses a problem, as the available carbonate ions, which are used by calcifying organisms to form their shells and skeletons, become fixed in an unusable bicarbonate form. When there isnt enough carbonate available for calcification, calcifying organisms suffer, and as conditions worsen, shells may begin to dissolve. The degradation of calcifying organisms will lead to widespread collapse of economically important fisheries, both directly and through trophic cascades. Some of the most obvious impacts are on crustacean fisheries, such as Maines American lobster fisheries. In these instances the target species is being immediately compromised by ocean acidification, which disrupts crustaceans immune systems, life history cycles and impairs formation of exoskeletons. Ocean acidification also has negative impacts on non-calcifying species fisheries. For example, salmon fisheries are suffering as a result of the impacts of ocean acidification on pteropods and coccolithophores. These plankton are the base of countless lucrative and threatened temperate fisheries. Known as isolated oases, coral reefs support large amounts of marine life and play an integral role in sustaining tropical marine fisheries. With increased ocean acidification, these ecosystems become increasingly threatened and could result in the loss of biodiversity, and ultimately, tropical fisheries.

https://digitalcommons.colby.edu/clas/2015/program/31