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.
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.