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Understanding the effects of ocean acidification on Dungeness crab

Dungeness crab in a crab hold. Credit: Austin Trigg, NMFS
  • Principal Investigator(s): Paul McElhany
  • Fiscal Year Funded: 2021, 2022, 2023

Understanding CO2 effects on Dungeness crab: population variability, temperature interactions, calcification process, and carbonate sensitivity

Why we care​
Dungeness crabs support the most valuable fishery on the U.S. West Coast. Previous research shows lower survival and slower development in Dungeness crab zoea, a young larval stage, when reared in high carbon dioxide conditions. This project helps us understand why, where, and under what conditions these effects occur. Answers to these questions will allow better projections of how Dungeness crab will fare in an acidifying ocean and provide critical data for projections of impacts on related species. 

What we are doing 
To test for local adaptation, this project investigates regional variation in Dungeness crab to acidification. Separate experiments aim to determine which of the carbonate chemistry parameters (pH, saturation state, partial pressure of carbon dioxide, dissolved inorganic carbon, and alkalinity) drive changes in Dungeness crab survival. The results will show which physiological processes are involved in responding to ocean acidification  and those we expect to drive any field observations of biological changes from ocean acidification. Lastly, we use stable calcium isotopes as labels to help understand the calcification process throughout the Dungeness crab molting cycle. We can then assess this as a potential cause of observed mortality and the utility of using exoskeleton condition as a field indicator of acidification. 

Benefits of our work
The research will explicitly evaluate potential mechanisms involved in observed field correlations between Dungeness crab larval exoskeleton morphology and ocean carbonate chemistry. These observations allow an assessment of Dungeness crab as a biological indicator of ocean acidification in the region. The study will elucidate the adaptive potential of Dungeness crab to ocean acidification, supporting better predictive models of crab populations.

Investigators
Paul McElhany, NOAA Northwest Fishery Science Center
Shallin Busch, NOAA Northwest Fishery Science Center

Collaborators
Alex Gagnon, University of Washington School of Oceanography
Chris Pearce, Department of Fisheries and Oceans Canada

ADAPTING TO OCEAN ACIDIFICATION

The NOAA Ocean Acidification Program (OAP) works to prepare society to adapt to the consequences of ocean acidification and conserve marine ecosystems as acidification occurs. Learn more about the human connections and adaptation strategies from these efforts.

Adaptation approaches fostered by the OAP include:

FORECASTING

Using models and research to understand the sensitivity of organisms and ecosystems to ocean acidification to make predictions about the future, allowing communities and industries to prepare

MANAGEMENT

Using these models and predictions as tools to facilitate management strategies that will protect marine resources and communities from future changes

TECHNOLOGY DEVELOPMENT

Developing innovative tools to help monitor ocean acidification and mitigate changing ocean chemistry locally

REDUCING OUR CARBON FOOTPRINT

50 more ways to reduce your carbon footprint >

On the Road

Drive fuel-efficient vehicles or choose public transportation. Choose your bike or walk! Don't sit idle for more than 30 seconds. Keep your tires properly inflated.

With your Food Choices

Eat local- this helps cut down on production and transport! Reduce your meat and dairy. Compost to avoid food waste ending up in the landfill

With your Food Choices

Make energy-efficient choices for your appliances and lighting. Heat and cool efficiently! Change your air filters and program your thermostat, seal and insulate your home, and support clean energy sources

By Reducing Coastal Acidification

Reduce your use of fertilizers, Improve sewage treatment and run off, and Protect and restore coastal habitats

TAKE ACTION WITH YOUR COMMUNITY

You've taken the first step to learn more about ocean acidification - why not spread this knowledge to your community?

Every community has their unique culture, economy and ecology and what’s at stake from ocean acidification may be different depending on where you live.  As a community member, you can take a larger role in educating the public about ocean acidification. Creating awareness is the first step to taking action.  As communities gain traction, neighboring regions that share marine resources can build larger coalitions to address ocean acidification.  Here are some ideas to get started:

  1. Work with informal educators, such as aquarium outreach programs and local non-profits, to teach the public about ocean acidification. Visit our Education & Outreach page to find the newest tools!
  2. Participate in habitat restoration efforts to restore habitats that help mitigate the effects of coastal acidification
  3. Facilitate conversations with local businesses that might be affected by ocean acidification, building a plan for the future.
  4. Partner with local community efforts to mitigate the driver behind ocean acidification  – excess CO2 – such as community supported agriculture, bike & car shares and other public transportation options.
  5. Contact your regional Coastal Acidification Network (CAN) to learn how OA is affecting your region and more ideas about how you can get involved in your community
       More for Taking Community Action