Effects of predicted changes in ocean pCO2 and interactions with other stressors on the physiology and behavior of commercially important crabs in Alaska
Why we care Ocean acidification disrupts the internal acid-base balance of crabs and may hinder the creation and maintenance of shells. Previous studies on commercially important crab species in Alaska found that ocean acidification changes physiology, decreases growth and condition, increases mortality, decreases hatching success, and changes exoskeleton (shell) hardness and structure in many Alaska crab species. Ocean temperature is a co-stressor, which may either decrease or increase the effects of ocean acidification on crabs. These individual effects may lead to population level decreases and impact coastal communities that rely on them if these crabs are unable to acclimate or adapt.
What we are doing The Alaska Fisheries Science Center (AFSC) aims to enhance our understanding of species responses to ocean acidification, predict how changes in ocean chemistry will affect marine ecosystems and organisms, assess socioeconomic impacts, and provide ocean acidification education and outreach. This project continues to assess the physiological response to ocean acidification of early life history stages in crabs. Researchers will examine the potential for acclimation of crab species through experimentation. Experimental data will be used to inform modeling efforts to assess the dynamics of the crab populations and coastal community resilience to future environmental changes in the ocean.
Benefits of our work The AFSC team will continue to address individual physiological responses that can be scaled to population level effects. Additionally, we will focus on cellular and molecular responses to better understand the potential for acclimation or adaptation. Results from this project will inform models, including stock assessments for long-term fisheries management through the North Pacific Fisheries Management Council.
Forecast effects of ocean acidification on Alaska crab and groundfish fisheries
Why we care Ocean acidification (OA) is a multi-disciplinary problem that requires a combination of methods from oceanography, fisheries science, and social science to assess socio-economic impacts. While OA impact models developed to date capture some sources of measurement uncertainty, more remains and limits the utility of models in decision making and research planning. A method is needed to quantify uncertainty relating the experimental design of OA experiments to the impacts of ocean pH and temperature on key model outcomes.
What we are doing The bioeconomic model developed under this project will be applied to forecasting long-term effects of OA on Eastern Bering Sea (EBS) crab, northern rock sole and Alaska cod. Also addressed in this project is the quantification of uncertainty for inclusion in the fisheries management process. The overall goal for this project is to forecast long-term effects of OA on abundance yields and fishery income. To this end, we will apply results from experiments and ocean monitoring/modeling to infer population-scale changes in juvenile growth and survival from OA.
Benefits of our work Through development of bioeconomic models for the EBS and Gulf of Alaska, we will be able to forecast the long-term effects of OA on northern rock sole and Alaska cod – a fish providing the vast majority of U.S. cod. These models make it possible to estimate abundance yields, fishery income, and economic impacts of OA on a national scale. The results from the project can assist with the development of experiments that will be most informative for bioeconomic modeling.