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Biological Response

Corals

Corals provide critical habitat to a diverse range of marine life. Numerous species, from tiny marine organisms to economically valuable fish and crabs, make their home in coral ecosystems in the shallow and deep ocean. Coral reefs also protect our coasts from storms and support tourism and recreation. Understanding the effects of ocean acidification on corals provides insight into future environmental changes that may impact entire food webs and coastal communities.

Both deep sea and shallow reef-building corals have calcium carbonate skeletons built with carbonate ions from seawater. As our oceans become more acidic, carbonate ions become relatively less abundant. Decreases in the availability of these building blocks makes it harder for corals to grow and maintain carbonate structures. The National Ocean Acidification Coral Reef Monitoring Program monitors the condition of U.S. coral reef ecosystems, while NOAA researchers study coral physiology and vulnerability.

Corals and fish in ocean
Shallow Coral
Shallow Water Corals

Shallow water corals typically build reefs with their accumulating calcium carbonate skeletons, which may be made of either aragonite or calcite, two forms of calcium carbonate mineral. Coral reefs occur globally in tropical environments and provide habitat to the greatest diversity of marine organisms in the world. The impacts of ocean acidification on shallow water corals are examined by the National Ocean Acidification Coral Reef Monitoring Program (NCRMP).

Red tree coral
Deep Sea Corals

Deep sea, or cold water, corals occur along the U.S. Pacific coast and are abundant throughout Alaska waters. While they do not form reefs in these regions, deep sea corals provide habitat for a variety of marine species. One of the most ecologically important deep sea corals is the red tree coral (Primnoa pacifica), which is found in the North Pacific Ocean from Washington to the Bering Sea. These corals can be very large (up to 5 meters high and wide) and provide essential habitat for managed fish and crabs. Scientists at the Alaska Fisheries Science Center and partner institutions document the forms of calcium carbonate that make up the skeletons of deep sea corals like the red tree coral, as well as their geographical location and depth. These efforts assist with assessing their vulnerability to ocean acidification.

Coral Reef Value, Research and Innovation

Explore the critical role of coral reefs as natural infrastructure and review NOAA’s latest data on restoration and disease mitigation.

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Bioeconomic modeling to inform Alaska fisheries management

Fishing Dock in Juneau Alaska
Image credit: Allen Shimada, NOAA NMFS

Bioeconomic models are a multidisciplinary tool that use oceanography, fisheries science and social science to assess socioeconomic impacts. Funded by the Ocean Acidification Program, researchers at the Alaska Fisheries Science Center use a bioeconomic model to study the impacts of ocean acidification on Eastern Bering Sea crab, northern rock sole and Alaska cod. The goal is to predict how ocean acidification will affect abundance yields and income generated by the fisheries. This work informs the potential economic impacts of ocean acidification and future decision making and research planning.

More about this work

Effects of ocean acidification and temperature on Alaskan crabs

Red King Crab
Image credit: David Csepp, NMFS AKFSC ABL

Long-term declines of red king crab in Bristol Bay, Alaska may be partially attributed to ocean acidification conditions. These impacts may be partially responsible for the fishery closures during the 2021–2022 and 2022–2023 seasons. Researchers found that ocean acidification negatively impacts Alaskan crabs generally by changing physiological processes, decreasing growth, increasing death rates and reducing shell thickness. Funded by the Ocean Acidification Program, scientists at the Alaska Fisheries Science Center continue to investigate the responses of early life history stages and study the potential of various Alaska crabs to acclimate to changing conditions. Results will inform models that will use the parameters studied to predict the effects of future ocean acidification on the populations of red king crab in Bristol Bay as well as on the fisheries that depend on them. Fishery managers will better be able to anticipate and manage stocks if changing ocean chemistry affects stock productivity and thus the maximum sustainable yield.

More about this work

Forecasts for Alaska Fisheries

Crab pots and fishing nets in Alaska's Dutch Harbor
Image credit: Michael Theberge

Understanding seasonal changes in ocean acidification in Alaskan waters and the potential impacts to the multi-billion-dollar fishery sector is a main priority. Through work funded by NOAA’s Ocean Acidification Program, the Pacific Marine Environmental Laboratory developed a model capable of depicting past ocean chemistry conditions for the Bering Sea and is now testing the ability of this model to forecast future conditions. This model is being used to develop an ocean acidification indicator provided to fisheries managers in the annual NOAA Eastern Bering Sea Ecosystem Status Report.

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

Closeup of oysters cupped in someone's hands

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