Alaskan Fisheries are being threatened from ocean acidification

Due to increases in the carbon dioxide (CO₂) caused by global human development, Alaskan Fisheries are being threatened from ocean acidification. There are at least two highly productive crab fisheries located in state that could be harmed by the uptake of atmospheric CO₂ into marine waters. A study published in Progress in Oceanography addresses this risk to our fisheries.

Ocean acidification is a term used to describe the decrease in pH and increase in carbonate ions caused by adsorption of CO₂ gas being pumped into the air. This greenhouse gas is produced primarily through the burning of fossil fuels. Many marine organisms depend on the deposition of calcium to build their shells or bodies. These include crab, coral and shellfish. Acidic water interferes with the construction of these shells.

Red King crab and Tanner crab, economically important species in Alaska, are seen as especially vulnerable to effects of ocean acidification. Due to the cold waters of the state, they take longer to develop their shells and are in contact with the acidic water longer. Additionally, this cold water adsorbs more CO₂ than waters found in lower latitudes and arctic currents force more acidic water towards the ocean’s surface.

In a press release, study co-author Steve Colt says, “Ocean acidification is not just an ecological problem — it’s an economic problem. The people of coastal Alaska, who have always looked to the sea for sustenance and prosperity, will be most affected. But all Alaskans need to understand how and where ocean acidification threatens our marine resources so that we can work together to address the challenges and maintain healthy and productive coastal communities.”

Studying the impact ocean acidification has to coastal communities, the researchers have made several recommendations to mitigate those effects. Some include monitoring conditions nearshore regions to verify modeling and identify the causes of acidification and to encourage the diversification of fisheries activities. The investigators highlight the importance of incorporating community stakeholder values in the development of response strategies to the effects of ocean acidification.

The paper, Ocean acidification risk assessment for Alaska’s fishery sector, can viewed at the Progress in Oceanography website.