Effects of OA on Alaskan and Arctic fishes: physiological sensitivity in a changing ecosystem

Why we care
There is significant concern about ocean acidification disrupting marine ecosystems, reducing productivity of important fishery resources, and impacting the communities that rely upon those resources. To predict the ecological and socioeconomic impacts of acidification, it is critical to understand the complex interactions between environmental stressors of physiology and ecology of marine fishes. Previous work on Alaskan groundfish focused on direct physiological effects of OA on early life stages. We need to further this work to understand the interaction between OA and co-stressors like elevated temperatures on fish productivity. 

What we are doing 
This AFSC project examines the interactive effects of OA and elevated temperatures on three fish species that are critical to Alaska and Arctic fisheries: Pacific cod, Arctic cod, and yellowfin sole. Laboratory experiments will track the impact of OA exposure on adult Arctic cod reproductive output, egg quality, and larval production. Further experiments will consider the potential for within-generation and trans-generational acclimation and adaptation to environmental changes. Risk assessments for regional fisheries will incorporate the data from this project.

Benefits of our work
Findings from this research will provide the foundation necessary to evaluate the ecological and socioeconomic impacts of ocean acidification in Alaskan and Arctic waters.

Resiliency and sensitivity of marine fish to elevated CO2: osmoregulatory neurosensory behavioral and metabolic responses in salmon and sablefish

Why we care
Elevated levels of marine carbon dioxide can disrupt how many marine fishes detect their environment, impairing their ability to respond appropriately to chemical, auditory, and visual cues. The mechanisms underlying differences in species sensitivity and resilience are poorly understood. This NWFSC project will explore the mechanisms underlying differences in carbon dioxide sensitivity between marine species that occupy habitats with different carbonate chemistries.

What we are doing
We will compare regulatory capabilities and behavioral responses of sablefish and salmon to improve our understanding of how future fish populations may adapt to changing ocean chemistries. Our primary objectives are to build on existing OA infrastructure and previous research at the Northwest Fisheries Science Center to determine: 1) the mechanisms underlying sablefish resilience to low pH waters, and 2) the potential behavioral and physiological impacts of low pH exposure in pink and Chinook salmon. 

Benefits of our work
Pacific salmon and sablefish are key species in the marine ecosystems of the western United States. They are an integral part of the history, culture, and economy of the West Coast and Alaska. This research advances our understanding of impacts of OA on salmon and sablefish behaviors and sensory systems. Findings enable fishery managers and scientific partners to identify species, populations, and geographic areas of concern. Ultimately, project results will inform managers about the resiliency and sensitivity of salmon to OA and assist their efforts for conservation priorities.

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.

Using next-generation sequencing techniques to assess adaptive capacity and illuminate mechanisms underlying the effects of high pCO2 on Alaskan crab and fish species

Why we care
Many economically important crab and fish species are negatively affected by exposure to ocean acidification predicted to occur throughout their ranges in the coming decades. Ocean acidification results in decreased growth, altered development, weaker exoskeletons, increased energy outputs, altered immune systems, altered behavior, and increased mortality in some of these species. Other stressors such as increased temperature can have interactive negative effects when combined with ocean acidification. Traditional laboratory experiments cannot duplicate the gradual changes that will affect species populations over multiple life-history stages and generations, so using next-generation genetic approaches provide insight into effects beyond specific life stages.