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PAGE TITLE SECTION SUBTITLE Spacing: leave 40 pt between top of section and first element leave at least 20 pt or multiple of 20 pt or 40 pt between all other elements leave at least 40 pt or multiple of 40 pt between last element and bottom of sections pin anchors to very top of section Button CANADA'S OCEAN ACIDIFICATION COMMUNITY OF PRACTICE Home About Events Blog JOIN US!

Strengthening BC's Coastal Future CLIMATE READY BC SEAFOOD PROGRAM Watch our short documentary on the Climate Ready BC Seafood Program! Ocean acidification and hypoxia threaten British Columbia's coastal food security. In 2023, concurrently with the release of the BC Ocean Acidification and Hypoxia Action Plan , the Province of British Columbia provided a $2M funding envelope to create the Climate Ready BC Seafood (CRBS) Program. This short documentary highlights some of the 11 projects funded by the CRBS Program. Learn more about how these groups are working to further our understand the impacts of ocean acidification and hypoxia in BC to provide knowledge for mitigation and adaptation that supports enhancing the resiliency of BC's seafood. JUMP TO: CRBS Program Information CRBS Project StoryMaps CRBS OAH Toolkit PROGRAM INFORMATION Lead Organizations Tula Foundation, Hakai Institute Province of British Columbia Project Description With support from British Columbia’s Ministry of Agriculture and Food, the Tula Foundation is delivering the Climate Ready B.C. Seafood Program. This program will provide $2 million in funding to support actions identified in the B.C. Ocean Acidification and Hypoxia (OAH) Action Plan . The B.C. OAH Action Plan was developed with support from an advisory committee and input from scientists, community members, aquaculture and fisheries representatives, Indigenous, Local, Provincial, and Federal governments. The Action Plan highlights the impacts of ocean acidification and hypoxia on marine organisms and ecosystems, with resulting effects on aquaculture and wild capture fisheries. Read the B.C. OAH Action Plan: https://www2.gov.bc.ca/assets/gov/environment/climate-change/adaptation/climate-risks/bc-ocean-acidification-hypoxia-action-plan.pdf The B.C. OAH Action Plan is supported by a comprehensive scientific assessment: https://www2.gov.bc.ca/assets/gov/environment/climate-change/adaptation/climate-risks/bc-ocean-acidification-hypoxia-scientific-assessment.pdf The Climate Ready B.C. Seafood program is addressing priorities identified in the Action Plan and aims to fund projects to support coastal communities in understanding, mitigating, and adapting to the impacts of OAH on B.C.'s oceans and coasts. In particular, the program will fund projects that support four key program areas: ● Advancing scientific understanding of ocean acidification and hypoxia (OAH) ● Collaborations, knowledge transfer, awareness and understanding related to OAH ● Mitigation, adaptation and resilience to OAH ● Interactions between Marine Carbon Dioxide Removal approaches and OAH Eleven proposals were selected for funding as they displayed strong alignments with program priorities, meaningful collaborations and high impact on understanding B.C. OAH. Successful proposal applicants include industry associations, research institutions, Indigenous communities and organizations, and non-profit organizations. Many successful proposals displayed strong collaborations and partnerships across stakeholders and rights holders. Projects will run from April 1, 2024 to March 31,2026. Full List of Awards BC OAH Action Forum On March 3, 2026, the BC Ocean Acidification and Hypoxia (OAH) Action Forum, hosted by the Tula Foundation, was held at the Vancouver Island Conference Centre in Nanaimo. The CRBS Program was strongly featured, including a premiere of the CRBS documentary, and lightning talks with panel discussions from the CRBS project recipients. To read the CRBS project abstracts and Forum Executive Summary, and explore other outputs of the Forum, please visit the Forum event page. BC OAH Action Forum event page Relevant Documents: List of Awards and CRBS Information Document RFP Information Document Related Programs Ocean Acidification Research for Sustainability (OARS) Canadian Ocean Acidification Community of Practice Relevant Links BC OAH Action Plan BC OAH Action Forum Contact Emily Paroo, Program Manager, Tula Foundation: emily.paroo@tula.org Credit: Bennet Whitnell, Videographer, Tula Foundation THE CRBS PROJECT STORYMAPS COMING SOON! THE CRBS EDUCATIONAL OAH TOOLKIT As part of the Climate Ready BC Seafood Program, an educational OAH toolkit was created by the CRBS administrative team to help bring together OAH resources relevant to BC and to connect them to the BC OAH Action Plan goals, objectives and actions. The toolkit was compiled during the CRBS Program (mainly 2024 - 2025) and is not an exhaustive list of OAH resources. Goals of the OAH toolkit: Assemble and organize resources related to ocean acidification and hypoxia (OAH) specific to British Columbia. Identify tools, guidance, and information relevant to addressing OAH impacts in BC and connect available resources to the actions identified in the BC OAH Action Plan. Process used: Searched for and compiled existing resources relevant to OAH, with a focus on BC-specific and regional resources where available. Organized resources according to their relevance to specific Action Plan actions to make them easier to identify and use. Included some resources from outside BC where they provided useful information or approaches that could be relevant to OAH work in the province. The toolkit was developed as a practical compilation rather than an exhaustive or systematic review, and resources were selected based on their relevance and usefulness at the time of compilation (2024/2025) To use this toolkit, we recommend viewing it in fullscreen by clicking the "view larger version" button in the bottom right corner of the viewer. The toolkit has a "Resources" tab that lists all of the resources compiled, which is filterable. The second tab lists all of the goals, objectives, and actions from the BC OAH Action Plan. Have a resource you'd like us to add? Last updated 2026-08-20 BACK TO TOP

Bringing together Canada's ocean acidification researchers, practitioners, policy-makers, & communities to share OA resources & expertise. Become a member of the Canadian OA Community of Practice today! NEW PAPER OCEAN ACIDIFICATION IN CANADA: THE CURRENT STATE OF KNOWLEDGE AND PATHWAYS FOR ACTION READ IT HERE REGIONS Stay up to date on current ocean acidification research, resources, facilities, and upcoming projects in your area! More Info RESOURCES Looking for more information on the resources and experts in your area? Want to learn more about OA action planning across Canada? More Info EVENTS Join us for online or in person conversations near you! View our upcoming event schedule and past event summaries... More Info OUR BLOG Featuring interviews with scientists, OA experts, and our OA CoP team, the latest in OA news, recaps of recent research, and more! More Info ABOUT US The Ocean Acidification Community of Practice was initiated in 2018 and is sponsored by the Marine Environmental Observation Prediction and Response (MEOPAR) Network. We are a UN Decade-Endorsed Project under the Ocean Acidification Research for Sustainability (OARS) Programme. Our overarching goals are to: Coordinate across all sectors, disciplines, and regions to share OA expertise and data and increase ocean literacy and OA resource development Identify pressing needs for OA research, knowledge, and actions needed in Canada Create a collaborative and supportive environment for groups affected by OA Learn More JOIN OUR COMMUNITY! Add your voice to our Canadian Ocean Acidification Community of Practice! Whether you're a seasoned ocean scientist, aquaculture operator, fisher, community or government representative, student, or concerned individual, everyone is welcome! Stay in the know! Membership is always free and signing up to our mailing list gives you first access to our monthly newsletters, new resources, and other important updates for the OA community in Canada. Our current members consist of individuals from government, aquaculture, fisheries, academia, and Indigenous community leadership, as well as students and members of the public. Join our OA CoP RECENT UPDATES BC OAH Action Forum Executive Summary Report Now Available! OA CoP Jun 8 New Paper: Acidification and CO2-Driven Conditions in the Estuary and Gulf of St. Lawrence During 2024 OA CoP May 27 Storytelling Illustrations from BC OAH Action Forum OA CoP May 11 1 2 3 4 5 CONTACT US coordinator@oceanacidification.ca Submit Thanks for your inquiry! contact

About the Collaboration The DFO/NOAA Ocean Acidification Collaboration is an ongoing effort to build an interagency framework between DFO and NOAA to coordinate research efforts in OA monitoring, modelling, and experimentation, as well as data and information sharing between the two federal agencies. Between November 2022 - May 2023, the Collaboration provided funding for the activities of Canada’s OA CoP, including the creation of outreach materials to jumpstart the DFO/NOAA OA Collaboration's ability to engage with stakeholders and potential members. Below, you will find examples of these activities, such as two-page poster highlights on some of the DFO/NOAA collaborative research projects and scientists who lead these initiatives, as well as a resource library. To learn more about the collaborative framework for joint DFO/NOAA ocean acidification research and monitoring, please visit DFO’s webpage on the collaboration here . Project Highlights Canada/US OA Resources Project Highlights DFO/NOAA OA COLLABORATION PROJECT HIGHLIGHTS Sally E Chris C Thomas H Emily S Halle B For more information about: "Impacts of Ocean Acidification on the Atlantic Sea Scallop" reach out to the lead scientists! Also check out this regional vulnerability assessment that project lead Halle Berger is working on for her PhD "Assessing Vulnerability of the Atlantic Sea Scallop Social-Ecological System in the Northeast Waters of the US" (funded by NOAA OAP) by clicking here! For more information about: "Impacts of coastal acidification and climate change stressors on the Atlantic sea scallop: larval supply, recruitment and adaptive capacity to multiple global change drivers" reach out to the lead scientists! Canada/US OA Resources CANADA/US OA RESOURCES BC OAH Action Plan The BC OAH Action aims to determine the state of knowledge related to ocean acidification and hypoxia in BC’s coastal waters, with long-term goals for addressing knowledge gaps and developing adaptation and mitigation strategies to support the fisheries and aquaculture sectors, traditional harvesters, and other BC seafood interests. Tsleil-Waututh Nation’s Climate Action Initiatives Tsleil-Waututh members have observed the effects of climate change in our territory for decades. OA is a concern to TWN, along with other ocean-related effects of climate change. Burrard Inlet is becoming more acidic, and research is underway to determine whether the cause is disproportionately associated with OA or if the reduction in pH is attributed to urban and industrial inputs. Acidification in Our Oceans This infographic developed by NOAA aims to teach the basics of ocean acidification and to provide information on what the reader can do to help this global problem. Ocean Acidification Building Blocks of the Sea This educational resource from NOAA, OAP and the National Marine Sanctuaries aims to have students understand the impact human activities can have on the chemistry/health of the ocean, and how changes in ocean ecosystems impact ocean and human life. Understanding Ocean and Coastal Acidification: Teacher Resources Through the lessons in this module, designed for grades 9-12, students will explore relationships between carbon dioxide, ocean pH and aragonite saturation state Coastal Acidification Interactive Story This educational module from NOAA is an interactive way to learn about the impacts of humans changing water chemistry. This module specifically focuses on how changing water chemistry results in coastal acidification Commonwealth Blue Charter: Ocean Acidification Action Group The Commonwealth Blue Charter is an agreement by all 54 Commonwealth countries, adopted at the Commonwealth Heads of Government Meeting in London, April 2018. New Zealand will champion the Ocean Acidification Action Group –improving the capacity of Commonwealth countries to address the impact of ocean acidification. OA CoP Educational Resource: How to make a Homemade pH Indicator in 5 Steps Educational Resource: How to make homemade pH strips in 5 easy steps Watch our new video on our YouTube channel or our tiktok to learn how to run the experiment DFO:What is Ocean Acidification? Ocean acidification is a global threat with potential impacts on marine food webs, ecosystem productivity, commercial fisheries and global food security. This threat has prompted the international scientific community, including Fisheries and Oceans Canada, to investigate the implications of this significant international governance issue. GOA-ON Pier2Peer Program Pier2Peer is a GOA-ON program that matches early career scientists with senior researchers across the globe. This program provides opportunities for knowledge exchange, conferences scholarships post doc positions and more! BC Climate Preparedness and Adaptation Strategy B.C.’s Climate Preparedness and Adaptation Strategy outlines four pathways to help ensure we stay safe and to prepare for a changing climate. The strategy highlights B.C.'s overall direction and actions that the Province is taking to help better understand and adapt to the impacts of climate change, and is supported by more than $500 million in funding. Alaska OA Network- Downloadable Resources The Alaska Ocean Acidification Network has created numerous infographics and downloadable visual resources. Check out these resources on their website! In 2019, the City of Vancouver declared a climate emergency, and in response focused on drastically cutting the city’s greenhouse gas emissions. The City of Vancouver has also registered our ocean acidification Framework, as a Voluntary Commitment to help support the implementation of the UN Sustainable Development Goal 14, Life Below Water. Vancouver Action Plan Baynes Sound Data This project aims to better understand the short- and long-term variability that occurs within these productive waters. With more data, it is hoped that producers will have the information needed to make the best decisions for their harvest. This online resource gives users access to real time ocean monitoring data in Baynes Sound. Understanding OA Learn how our oceans are absorbing increasingly more carbon dioxide from the atmosphere, leading to lower pH and greater acidity with this educational resource from NOAA. Ocean acidification is fundamentally changing the chemistry of the world’s oceans and threatening our marine resources. Whale Jenga: A Food Web Game This educational resource from NOAA and the National Marine Sanctuaries aims to have students understand how organis ms are connected through the marine food web and how small changes to to food webs can have larger scale impacts. DITC CIA Worksheet: How Does Rising CO2 Impact Ocean pH? This "Data in the Classroom" (DITA) worksheet aims to teach the impacts of CO2 on the ocean by studying important graphs and figures, which encourages students to think deeper about ocean chemistry. Crabs in a Changing Ocean This infographic from NOAA and National Marine sanctuaries, outlines how crabs will be impacted by changing water chemistry and what you can do to help! OA Alliance The OA Alliance is an international organization whose goal is to create a network of governments and organizations. They use this network to take action against the growing threat of Ocean Acidification to protect coastal communities all over the world. Create an Ocean Acidification Action Plan! Action Plans can be used by more people than just governments, they can be used by any individual or group that is faced with a problem! We have created an educational resource outlining how to design a Action plan of your own that can be used to address OA in your community and beyond! This resource is targeted for students but could be used by anyone looking to make an action plan! Ocean Acidification Information Exchange Have professional questions about OA, how to conduct research, data set, and more? Connect with the Canadian and global OA communities here! GOA-ON Data Explorer The GOA-ON data portal "provides access and visualization to ocean acidification data and data synthesis products being collected around the world from a wide range of sources, including moorings, research cruises, and fixed time series stations" and represents them as an easy-to-use map. The map contains worldwide (and in some cases also real-time!) data and observation assets which are represented as interactive icons. Climate Change and Ocean Acidification: Olympic Coast- Video In recent years, shellfish growers in Washington state have needed to develop monitoring and treatment practices to avoid spawning failures that have been linked to periodic upwelling of more acidic ocean waters. Read this overview of OA research on the Olympic coast! The Olympic Coast as a Sentinel Video This webinar funded by the NOAA OAP focuses on regional vulnerability assessment and the 4 Olympic Coast Tribes who depend on local marine species that are at risk from ocean acidification. B.C. is focused on implementing CleanBC; the actions and commitments in CleanBC will reduce the causes of ocean acidification and help to build adaptation and resiliency of coastal communities BC OA Case Study Back to Blue Initiative: An Ocean Crisis in the Making The Back to Blue Initiative has created an interactive webpage that educates the user on the basics of ocean acidification. These basics are broken down into an introduction, the science, the impacts, and soultions? Ocean Acidification: pH and the Ocean's Balance This educational resource from NOAA, OAP and the National Marine Sanctuaries aims to have students understand the pH is a measurement of ocean acidification, understand the pH scale, and the impacts that small changes to this scale can have. Dungeness Crab Case Study Resources Dungeness crab is a valuable species throughout the National Marine Sanctuaries of the West Coast from Washington state to throughout California. This communication toolkit is designed for educators and communicators to use to teach others about the impact of ocean acidification on Dungeness crab. NOAA: Ocean Acidification This NOAA webpage walks you through the basics of ocean acidification, highlighting the impacts on important organisms, and the current research in the USA. Commonwealth Blue Charter: Ocean Acidification Policymakers Handbook The Commonwealth Blue Charter helped put together an Ocean Acidification policymakers handbook. This contains many of the tools that a policy maker needs to be acquainted with to effectively make decisions about Ocean Acidification. UN Ocean Decade: OARS Ocean Acidification Research for Sustainability (OARS). The programme will address the SDG target 14.3 ‘Minimize and address the impacts of Ocean Acidification (OA), including through enhanced scientific cooperation at all levels’. DFO: Ocean Acidification Video This video from the DFO-Canada outlines how the levels of carbon dioxide in the atmosphere have continued to increase due to human activities, lowering the pH of the ocean and making it more acidic. This process of ocean acidification increasingly affects ecosystems and those communities that directly rely on the ocean. GOA-ON Sampling Standards Global Ocean Acidification Observing Network (GOA-ON) sampling standard gives guidance on the proper way to execute ocean acidification observations, to allow for data to be compared world wide. It also gives advice on what to kinds of data to collect and and how to submit to the SDG 14.3.1 Indicator, for world-wide comparison. OA-ICC Biological Response Portal This easy-to-use data repository and publication catalog focuses on biological response to ocean acidification. This resource allows you to easily search existing datasets through easy-to-use filters under the categories of Spatial information, Experimental information, Biological information, and Bibliographic information (as can be seen in the image below). Ocean Acidification Impact on Oysters and Other Shellfish-Video PMEL Carbon Program Video- The world's oceans are absorbing carbon dioxide at an unprecedented rate and the resulting acidification is transforming marine ecosystems. Hari Sreenivasan, of PBS NewsHour reports on how ocean acidification is already affecting oysters and other shellfish in the U.S. Keepin' it Real: Connecting Ocean Acidification to Watershed Health and Promoting Student Action- Video This webinar funded by the NOAA OAP focuses on using the "Virtual Urchin" education tool which can be used by students and teachers to see real lab data and an action module. NOAA Archived Webinars The National Oceanic and Atmospheric Association has a collection of archived educational webinars targeted at students and teachers available on their website. Click the image to begin exploring these resources.

WHAT IS OEAN ACIDIFICATION? Ocean acidification (OA) is the process where carbon dioxide is absorbed by the oceans, causing a chemical reaction that leads to a reduction in seawater pH. The oceans absorb about one third of these carbon dioxide emissions every year. Since the industrial revolution, the burning of fossil fuels has led to an exponential increase of carbon dioxide in the atmosphere, resulting in an approximately 30% increase in ocean acidity. As carbon dioxide levels in the atmosphere continue to rise, so will the ocean’s acidity. One of the major consequences of ocean acidification is decreases in the amount of shell-building materials available to shelled organisms, such as oysters, mussels, and corals. Ocean acidification is also harmful to the development and bodily functions of many organisms, such as crabs, lobsters, and fish, and can even impact normal animal behaviour. Many of the species most vulnerable to ocean acidification are critical habitat formers and sources of food for their ecosystems, such as oysters, mussels, and many types of plankton. A lot of the species most impacted by ocean acidification are also important economic and food resources for humans, including important shellfish such as oysters, mussels, crabs, and lobsters. How is Canada impacted by OA? Canada has the longest coastline of any country in the world and is surrounded by three ocean basins all with unique dynamic processes. Situated at high latitudes, the waters surrounding Canada are also naturally more vulnerable to OA, as carbonates are more soluble in cold water. Each coastal region in Canada faces its own set of challenges when it comes to OA. In the Pacific , seasonal upwelling brings naturally acidic waters close to the ocean’s surface, negatively impacting important shellfish like oysters. The cold waters of the Arctic are especially vulnerable to OA due to increased absorption of atmospheric carbon dioxide and freshwater input that both increase seawater acidity and decreasing ice cover that further accelerates these processes. Ocean acidification in Atlantic Canada is influenced by both the input of acidic Arctic waters from the Labrador Sea, as well as the St. Lawrence, and threatens many socioeconomically important shellfish such as lobsters and scallops. Learn more about how OA is impacting Canada with this short infographic video from DFO.

EVENTS Upcoming Events Past Events Webinars Other Useful Events UPCOMING EVENTS UPCOMING EVENTS Geological Association of Canada - Mineralogical Association of Canada GAC-MAC) Annual Meeting (May 25 - 28, 2026, St. John's NL) Session of Interest: Ocean Acidification and its consequences: past, present and future (ss-20 Environmental Geology) Session description: Ocean Acidification (OA), the broadscale change in ocean pH associated with changes in atmospheric chemistry, is considered the “evil twin” of modern anthropogenic climate change. Recent re-analyses of mass extinction events and other events in the deep-time history of Earth have revealed tight linkages between atmospheric/ocean temperature and chemistry change and biotic consequences, with long-term evolutionary responses in some cases. A deeper understanding of the chronologies and mechanisms of these atmospheric/ocean chemistry changes and their biotic consequences in the past is valuable for understanding OA in the Anthropocene, and modelling OA responses in the 21st century and beyond. This special session seeks submissions investigating all aspects of OA and its ecological, evolutionary, oceanographic and stratigraphic consequences, throughout Earth History. Conference website: https://event.fourwaves.com/stjohns2026/pages or https://gac.ca/events/gac-mac-annual-meeting/ The Ocean in a High-CO2 World Ocean Acidification 6th International Science Symposium (October 13 - 16, 2026, Wellington, New Zealand) About the Symposium (from website): "Ocean acidification remains a central theme of the symposium series. This edition will also expand to consider other ocean climate impacts, such as ocean warming and deoxygenation, particularly in a multiple-driver context. Research on marine carbon dioxide removal interventions, which are suggested to mitigate climate change and ocean acidification, will also be a key part of the conference." Themes: Beyond tipping points - translating science to action Global-driven changes in biodiversity and ecosystem resilience Multiple stressors' effects on marine organisms Ocean-based solutions Technological advances in marine climate change research The modulating role of time - from short-term variability to evolution Working across knowledge systems in a high-CO₂ world Abstracts are due April 1, 2026. Call for abstracts Special Sessions - includes "Ocean acidification multiple stressor effects on North American species" PAST EVENTS PAST EVENTS BC OAH Action Forum March 3, 2026 The BC Ocean Acidification and Hypoxia (OAH) Action Forum, hosted by the Tula Foundation, aimed to chart progress made and next steps for BC's OAH Action Plan. Learn more... Past Webinars Browse and view our past webinars here! PAST EVENT UPDATES BC OAH Action Forum Executive Summary Report Now Available! OA CoP Jun 8 Storytelling Illustrations from BC OAH Action Forum OA CoP May 11 New Short Documentary: the Climate Ready BC Seafood Program OA CoP Apr 14 OA Day of Action 2026 OA CoP Jan 8 October 2025 Updates OA CoP Oct 29, 2025 OA Week 2025 OA CoP Oct 27, 2025 OA CoP Strategic Planning "What We Heard" Report OA CoP Oct 14, 2025 September 2025 Updates OA CoP Sep 29, 2025 August 2025 Updates OA CoP Aug 28, 2025 1 2 3 4 5 OTHER USEFUL EVENTS OTHER USEFUL EVENTS MEOPAR Events GOA-ON Events OA Alliance Events The MEOPAR Ocean Acidification Community of Practice takes no responsibility for the content, publications, products, funders, or services of linked websites, nor any views expressed on external sites. Links to other websites are included for resource sharing, transparency and convenience only.

SPECIES IMPACTS There are many species in Canada that are vulnerable to ocean acidification. Across the country, research is being conducted to understand how species respond to OA (and other co-stressors, such as changing ocean temperature and oxygen levels), but there are still many unknowns . Below are resources summarizing our current understanding of how species are responding to OA in Canada, including our newly published OA in Canada paper with a full list of species responses! Explore Full Responses Explore by Species Industry Impacts Explore by Region OA IN CANADA SPECIES RESPONSES FROM BARCLAY, GURNEY-SMITH ET AL., 2026 Calcification Growth Survival Reproduction Physiology Ecosystem Role Economic Role Pacific Arctic Atlantic References Plankton Sea - ice microbes NE ●● NE ●● Basal food web, mixotrophs ●● (1,2) Phytoplankton ▲ ●○ M ●● M ( ▼ - NE) ●● Basal food web, primary producers ● ●●● ●●● ( 3 – 13) Foraminifera NE ●● Basal food web, mixotrophs Ø Ø ● (9) Arthropods (copepods, amphipods) M ( ▼ - NE) ●● Basal food web, consumers Ø ● ● ( 12,14) Pteropods (shelled) Limacina helicina ▼ ●○ M ( ▼ - NE) ●●● Basal food web, consumers ●● ●● ● ( 9,15 – 18) Pteropods (non - shelled) M (NE - ▲ ) ●● Basal food web, consumers ● Ø Ø ( 16) Pelagic species Salmon, Pacific pink Oncorhynchus gorbuscha M ( ▼ - NE) ●● NE ●● ▼ ●● Predator C, R, F ●● ( 19,20) Salmon, Pacific chum Oncorhynchus keta ▼ ●● ▼ ●● Predator C, R ● ( 21) Herring, Pacific Clupea pallasii NE ●● M ( ▼ - NE) ●○ ▼ ●● Planktivore C, R ● ( 22) Stickleback, Three - spined Gasterosteus aculeatus ▼ ●● Omnivore ● Ø ( 23) Redfish Sebastes fasciatus NE ●● NE ●● M ( ▼ - NE) ●○ Predator C, R ● (24) Benthic species Shrimp, northern Pandalus borealis M ( ▼ - NE) ●●○ M ( ▼ - NE) ●●○ Omnivore C, R Ø Ø ●●● ( 25 – 29) Crab, Dungeness Metacarcinus magister ▼ ●●○ Predator C, R ●● (30,31) Crab, European green Carcinus maenus ▼ ●● Predator I ● Ø (32) Crab, yellow shore Hemigrapsus oregonensis ▼ ●● Omnivore ● (33) Lobster, American Homarus americanus M ( ▼ - NE) ●● M ( ▼ - NE) ●● ▼ ●●● Predator C, R ●●● ( 34 – 38) Amphipods ▼ ●● ▼ ●●● Omnivore I ● ● ( 39,40) Clam, softshelled Mya arenaria M ( ▼ - NE) ●○ ▼ ●● M ( ▼ - NE) ●●○ M ( ▼ - NE) ●●○ Suspension feeder R, F Ø ●●● (40 – 45) Mussel, blue Mytilus edulis ▲ ●● NE ●●○ NE ●● NE ●● Habitat former, suspension feeder R, F Ø ●● ( 46,47) Mussel, Pacific blue Mytilus trossulus M ( ▼ - NE) ●● ▼ ●●● ▼ ●● NE ●● Habitat former, suspension feeder R, F ●●● ( 48 – 51) Mussel, Mediterranean Mytilus galliprovincialis ▼ ●● NE ●● Habitat former, suspension feeder F ● (51) Oyster, Eastern Crassostrea virginica M ( ▼ - NE) ●● ▼ ●● ▲ ●● ▲ ●● NE ●● Habitat former, suspension feeder C, R, F ●●● (52 – 54) Oyster, Pacific Crassostrea gigas ▼ ●●○ ▼ ●●○ * ▲ ●●○ ▼ ●● H abitat former, suspension feeder R, F ●●● ( 55 – 57) Abalone, northern/pinto Haliotis kamtschatkana ▼ ●● ▼ ●● ▼ ●● NE ●● H erbivore E ● ( 58) Snail, northern moon Euspira heros M ( ▼ - NE) ●● Predator R ● ( 59) Snail, common periwinkle Littorina littorea M ( ▼ - NE) ●● Herbivore R ● ( 59) Snail, frilled dogwhelk Nucella lamellosa M ( ▼ - NE) ●● Predator ● (60) Snail, Eastern mud Illyanassa obsoleta M ( ▼ - NE) ●● NE ●● M ( ▼ - NE) ●● Detritivore ● (40) Sponges ▼ ●● ▼ ●● ▼ ●● ▼ ●●○ Habitat former, suspension feeder ●● Ø ● (50,61,62) Sea star, common Asterias rubens ▼ ●● Predator ● ( 46) Sea star, ochre Pisaster ochraceus ▼ ●● ▲ ●● ▲ ●● Predator ● (63) Urchin, red Mesocentrotus franciscanus ▼ ●● M ●● Herbivore C, R ●● ( 48,64) Sea cucumber, northern Cucumaria frondosa ▼ ●● ▼ ●● ▼ ●● ▼ ●● NE ●● Detritivore C, R Ø ● ( 65) Deep sea polychaete Op hryotrocha sp. NE ●● ▼ ●● ▼ ●●● ▼ ●● Detritivore Ø Ø ●● (66) Bryozoan, kelp/lacy Membranipora membranacea ▲ ●●○ NE ●●○ Biofouling, suspension feeder I ●● Ø (49, 50) Tunicate, colonial sea squirt Didemnum sp. NE ●● NE ●● Biofouling, suspension feeder I ● Ø (50) Tunicate, star Botryllus schlosseri ▼ ●● Biofouling, suspension feeder I ● Ø (50) Parasites Trematode parasite Himasthla sp. ▼ ●● Parasite ● Ø Ø ( 67) Mud blister worm Polydora websteri M ( ▼ - NE) ●● Parasite ● (52) Marine vegetation Coralline algae NE ●●○ NE ●●○ NE ●● Primary producer , habitat former ● ● ●● ( 68 – 70) Rockweed Fucus distichus ▼ ●● NE ●● NE ●● Primary producer , habitat former ● Ø Ø (71) Figure 4. (Barclay, Gurney-Smith et al., 2026). Table showing species responses to OA from studies conducted in Canada. Responses are: ▼ – negative, ▲ – positive, NE – no effect, M – mixed (positive, negative, no effect), M (▼ - NE) – mixed (negative - no effect), M (NE - ▲) – mixed (no effect -positive), * - Selectively bred oysters showed increased resilience to OA. Confidence levels follow the style of IPCC WG II (IPCC, 2023) in terms of number of studies and are: ● – low, ●○ – medium low, ●● – medium, ●●○ – medium high, ●●● – high. Economic Role abbreviations: C – commercial fishery, R – recreational fishery, F – farmed/aquaculture, I – invasive species, E – endangered species. Ranges (Pacific, Arctic, Atlantic): ● – present, low evidence (1 study), ●● – present, medium evidence (2 studies), ●●● – present, high evidence (3+ studies), Ø – present, no data. View paper here: https://doi.org/10.3389/fmars.2026.1761703 OA IN CANADA SPECIES SPOTLIGHTS American lobster Download our poster here! Pacific oyster Download our poster here! Pink salmon Download our poster here! Northern shrimp Download our poster here! Dungeness crab Download our poster here! Other Species Download our poster here! VIEW ALL POSTERS More species coming soon! EXPLORE MORE PAST POSTS FROM OUR MEET THE CRITTERS BLOG SERIES New Short Documentary: the Climate Ready BC Seafood Program New Paper: Ocean Acidification in Canada: the current state of knowledge and pathways for action OA in Canada Species Impacts: Dungeness Crab 1 2 3 4 5 FISHERIES AND AQUACULTURE IMPACTS Seafood Industry Download our poster here! $1,764 $889 $312 $119 $109 $68 $45 $31 $14 $500 $365 $196 $54 $29 $0.2 $0 $200 $400 $600 $800 $1,000 $1,200 $1,400 $1,600 $1,800 Lobster Salmon Shrimp Crab (Other) Clams Oyster Mussels* Herring Sea urchin Queen/snow crab Groundfish Scallop Pelagic fish (other) Shellfish (other) Others Value (Millions, CDN) Canada Seafood Industries ($4.5B) - Vulnerability to OA ■ Negative ($2.21B, 49%) ■ Mixed (negative - no effect) ($1.03B, 23%) ■ Mixed ($113M, 3%) ■ Unknown in Canada ($1.14B, 25%) FAST FACTS 25% ($1.14B) of seafood species in Canada require more research on OA impacts , such as: Queen/snow crab (11% or $500M) Scallops (4% or $196M) Fish ( 10% or $419M) 49% ($2.21B) of seafood species are negatively impacted by OA 23% ($1.03B) have reported mixed negative effects (negative - no effect) 3% ($113M) have mixed responses (negative - positive) Values reported here are based on seafisheries landings values and aquaculture production values reported by DFO in 2023: 1. https://www.dfo-mpo.gc.ca/stats/commercial/land-debarq/sea-maritimes/s2023pv-eng.htm 2. https://www.dfo-mpo.gc.ca/stats/aqua/aqua23-eng.html *Mussels include aquaculture only Seafood Industry Impacts by Province FISHERIES AND AQUACULTURE IMPACTS BY PROVINCE BC QC NB PEI NS NL $528 $73 $114 $80 $16 $4 $5 $8 $148 $1 $6 $9 $0 $100 $200 $300 $400 $500 $600 Salmon Shrimp Crab (Other) Clams Oyster Mussels* Herring Sea urchin Groundfish Scallop Pelagic fish (other) Shellfish (other) Value (Millions, CDN) BC Seafood Industries ($992M) - Vulnerability to OA ■ Negative ($195M, 20%) ■ Mixed (negative - no effect) ($613M, 62%) ■ Mixed ($21M, 2%) ■ Unknown in Canada ($164M, 16%) $242 $15 $2 $1 $3 $0.4 $1 $5 $78 $13 $3 $0.4 $0 $50 $100 $150 $200 $250 Lobster Shrimp Crab (Other) Clams Oyster Mussels* Herring Sea urchin Queen/snow crab Groundfish Scallop Pelagic fish (other) Value (Millions, CDN) Quebec Seafood Industries ($360M) - Vulnerability to OA ■ Negative ($264M, 73%) ■ Mixed (negative - no effect) ($2M, 1%) ■ Mixed ($3M, 1%) ■ Unknown in Canada ($94M, 26%) $290 $258 $3 $1 $0.2 $26 $4 $1 $68 $2 $15 $4 $0 $50 $100 $150 $200 $250 $300 Lobster Salmon Shrimp Crab (Other) Clams Oyster Herring Sea urchin Queen/snow crab Groundfish Scallop Pelagic fish (other) Value (Millions, CDN) NB Seafood Industries ($673M) - Vulnerability to OA ■ Negative ($295M, 44%) ■ Mixed (negative - no effect) ($263M, 39%) ■ Mixed ($26M, 4%) ■ Unknown in Canada ($89M, 13%) $290 $2 $1 $19 $29 $2 $24 $1 $0.04 $4 $0 $50 $100 $150 $200 $250 $300 Lobster Crab (Other) Clams Oyster Mussels* Herring Queen/snow crab Groundfish Scallop Pelagic fish (other) Value (Millions, CDN) PEI Seafood Industries ($372M) - Vulnerability to OA ■ Negative ($291M, 78%) ■ Mixed (negative - no effect) ($3M, 1%) ■ Mixed ($48M, 13%) ■ Unknown in Canada ($30M, 8%) $821 $103 $69 $1 $27 $4 $3 $10 $77 $120 $174 $27 $0 $100 $200 $300 $400 $500 $600 $700 $800 $900 Lobster Salmon Shrimp Crab (Other) Clams Oyster Mussels* Herring Queen/snow crab Groundfish Scallop Pelagic fish (other) Value (Millions, CDN) NS Seafood Industries ($1.4B) - Vulnerability to OA ■ Negative ($891M, 62%) ■ Mixed (negative - no effect) ($140M, 10%) ■ Mixed ($7M, 0.5%) ■ Unknown in Canada ($397M, 28%) $121 $153 $8 $9 $1 $253 $82 $3 $13 $20 $0.2 $0 $50 $100 $150 $200 $250 $300 Lobster Shrimp Mussels* Herring Sea urchin Queen/snow crab Groundfish Scallop Pelagic fish (other) Shellfish (other) Others Value (Millions, CDN) NL Seafood Industries ($662M) - Vulnerability to OA ■ Negative ($271M, 41%) ■ Mixed (negative - no effect) ($9M, 1%) ■ Mixed ($8M, 1%) ■ Unknown in Canada ($371M, 56%) EXPLORE SPECIES IMPACTS BY REGION PACIFIC Pacific oyster Download our poster here! 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VIDEO TUTORIAL: MAP OF CANADA'S OA RESOURCES

ATLANTIC Map of Canada's OA Resources Explore OA monitoring assets, experimental infrastructure, and modelling domains in your region! OA in Canada Paper Learn more about OA monitoring, experiments, models, policies, and more in Atlantic Canada in our new paper: OA in Canada: the current state of knowledge and pathways for action From the Blog Explore our updates and blog stories from Atlantic Canada! Species Impacts Learn more about how Atlantic species in Canada are impacted by OA! OARS Committment: Projections and impact of ocean acidification in the Gulf of St. Lawrence, Maurice-Lamontagne Institute. Learn more! StoryMap Coming soon! Find an Expert Looking to connect with an OA expert in your area? Check out or OA in Canada Expert Database! Share your project! Collecting OA data in Atlantic Canada? Have an ongoing (or past) OA project? We want to hear from you! Atlantic Blog Feed FROM THE BLOG New Paper: Acidification and CO2-Driven Conditions in the Estuary and Gulf of St. Lawrence During 2024 OA CoP May 27 New Paper: Ocean Acidification in Canada: the current state of knowledge and pathways for action OA CoP Feb 13 OA Day of Action 2026 OA CoP Jan 8 October 2025 Updates OA CoP Oct 29, 2025 OA Week 2025 OA CoP Oct 27, 2025 OA CoP Strategic Planning "What We Heard" Report OA CoP Oct 14, 2025 1 2 3 4 5

OA IN CANADA EXPERT DATABASE In an effort to improve connections between ocean acidification researchers, community members, and OA resources, the OA CoP has created an online public database of OA experts across Canada. Please feel free to explore and let us know what you think! For people who would like to add themselves to our database, we have created a Google form for you to fill out your desired contact information and details on your areas of research/expertise. You have the option to include or exclude your email address. Once you submit this form, we will then add you to our public OA in Canada Expert database (see below). Our eventual goal is to make this database more interactive, including potentially developing a geographic map of experts and/or the areas/facilities where they conduct their research. Feedback and suggestions are always welcome as we develop these resources (email coordinator@oceanacidification.ca ). If you are interested, you can also join Team Canada on the OA Info Exchange . Details are included in the form. Add yourself to our database

CANADA'S OA RESOURCES NEW! MAP OF CANADA'S OA ASSETS Check out our new interactive map of Canada's OA assets, including monitoring cruises, stations, labs with OA experimental infrastructure, and models! From Barclay, Gurney-Smith et al., 2026: https://doi.org/10.3389/fmars.2026.1761703 View Fullscreen Note: this map will be updated regularly, so please contact us if you have assets you'd like to see added! Find out more about the OA resources in your area! Our map of Canada's OA resources is full of information on OA facilities, infrastructure, experts, research groups, past and ongoing projects, and more! Each map pin has an up-to-date link of its available material and a list of searchable keywords. Instructions: Click on pins to view info Each pin has a webpage link that contains all resources for that pin, and a list of searchable keywords (listed under "description") To view layers (e.g., Facilities, People, Projects), expand map menu (top left button) and check/uncheck layers To search map, click "view larger map" icon in top right corner (this opens a new tab with our map where you can search, with results from both our map and Google Maps). Legend: Facilities & Infrastructure People & Groups OA Projects Unsure of how to use the map? Click here for our video tutorial! Map Tutorial We are continuously working to keep this map updated, so please let us know if you have an OA resource you would like us to add! Contact us

Strengthening BC's Coastal Future BC OAH Action Forum March 3, 2026 On March 3, 2026 , the BC Ocean Acidification and Hypoxia (OAH) Action Forum , hosted by the Tula Foundation, was held at the Vancouver Island Conference Centre in Nanaimo. Forum Executive Summary Forum Outputs This gathering united scientists, government representatives, Indigenous groups, community members, and members of the seafood industry to reflect on progress made through BC’s OAH initiatives. Organizers aimed to chart the next phase toward protecting the province’s marine ecosystems and coastal economies from ocean acidification and hypoxia, two major stressors associated with climate change. Ocean acidification and hypoxia pose major risks to BC’s seafood industries, with projected losses in the hundreds of millions by 2050. In response, the Province of BC released the BC OAH Action Plan in 2023 , developed with input from scientists, communities, Indigenous groups, and government representatives. Since its release, the Province has invested $2 million into 11 OAH research and mitigation projects through the Climate Ready BC Seafood Program . The goals of the forum were to: Assess achievements and opportunities within the Climate Ready BC Seafood Program ; Summarize ongoing OAH mitigation efforts across all sectors; Document accomplishments and remaining needs under the BC OAH Action Plan; Bridge knowledge, networks, and efforts to foster long-term collaborations supporting sustainable OAH initiatives. The forum and its outputs will be critical in identifying priority next steps to help safeguard coastal resources against OAH, in alignment with the BC provincial governments Coastal Marine Strategy and Climate Preparedness and Adaptation Strategy. Missed the forum? Watch it here ! FORUM OUTPUTS BC OAH Action Forum Outputs GRAPHICAL SUMMARIES OTHER OUTPUTS Forum Executive Summary Report Forum Agenda Forum Abstract Booklet Full Forum Video Recording Climate Ready BC Seafood Documentary Animated video: OAH in BC BC OAH Action Plan Case Study: UN Decade OARS Programme Stay tuned for more! Relevant Links: BC OAH Action Plan Climate Ready BC Seafood Program