Our October updates are here, featuring upcoming BC OAH Action Forum, our OA CoP presentation for OA Week, our community strategic planning "What We Heard" report, and more! View our updates here: https://mailchi.mp/048a51dd189c/oa-cop-october-2025-updates If you'd like to receive these updates, sign up for our membership at https://www.oceanacidification.ca/join-us !

OA Week 2025 was held Oct. 13 - 17 and was a huge success! This year's theme was:  Rising to the challenge of ocean acidification: using science and knowledge to drive action ​ The OA CoP participated in the GOA-ON North American Hub session, where Dr. Kristina Barclay, Coordinator for the OA CoP, will presented on the state of Canada's OA knowledge! OA CoP Co-Lead, Dr. Helen Gurney-Smith, also moderated the session. View the recording here! You can also watch all of the other OA Week sessions here!

In April, 2025, the OA CoP held a strategic planning meeting with many members of our community. The goals of the meeting were to seek expert feedback on the future direction of the OA CoP, develop actionable priorities and recommendations for the OA Community in Canada, and suggest what role the OA CoP should have in the development of these priorities. After the meeting, we circulated an initial draft of the "What We Heard" report to meeting attendees for feedback that was then revised based on the feedback we received and circulated for one final round of comments. Here we present the finalized version of this community-led "What We Heard" report, with eight major recommendations from our community, and some notes on progress made towards these recommendations since April, 2025. Read the report here:

Our September updates are here, including updates for OA Week  2025 (including an OA CoP presentation), new Scientist Spotlight post, and more! View our updates here: https://mailchi.mp/d41d6b690386/oa-cop-september-2025-updates If you'd like to receive these updates, sign up for our membership at https://www.oceanacidification.ca/join-us !

Virginie Chalifoux is a Ph.D. student in Applied Animal Biology in the Faculty of Land and Food Systems at the University of British Columbia. Her work explores the relationships between fish ecology and their responses to climate change stressors. Virginie shares with us her background, ongoing research, and interests in ocean acidification and fish ecology. Virginie Chalifoux (Photo credit: Radio-Canada/Camille Vernet https://ici.radio-canada.ca/recit-numerique/12610/ocean-oeufs-biodiversite-poissons-cb ). What is your background? I am a PhD student at the University of British Columbia who started my third year in Applied Animal Biology. My work focuses on evaluating the effects of anthropogenic disturbances on two economically, culturally and ecologically important fish for British Columbia, which are salmon and herring. In this broad subject, I am interested in how ecology can help shape the climate change response of these fish. Before pursuing my PhD, I completed a M.Sc. in oceanography at the Institute of marine science of the Université du Québec à Rimouski in Québec, where I am from. At that time, I applied my research to fisheries management by evaluating a bioenergetics model for brook charr, a species native to Québec but invasive in British Columbia, under two salinity conditions. My passion for fish research fuelled my whole journey while my curiosity in ocean acidification (OA) sparked when I started the PhD. Another interest of mine is to collaborate and share my research with the concerned communities to help in making decision for the environment. I believe that the people who knows the most pressing concern about resources such as fish are the ones in daily contact with it. As such, I collaborated with the Átl'ḵa7tsem/Howe Sound Marine Stewardship Initiative ( https://howesoundguide.ca/ ), who monitors herring spawn events every year in Squamish, to collect herring embryos for my experiment. Listening to their concerns about herring helped me design my experiment in a way that provides answers relevant to their needs. I then shared my knowledge about herring and the results from my experiment to the community afterwards. Both their work and my research attracted media coverage in French that can be watched using this link:   https://ici.radio-canada.ca/recit-numerique/12610/ocean-oeufs-biodiversite-poissons-cb   Collecting herring embryos on seaweed in Átl'ḵa7tsem/Howe Sound near Squamish with the Marine Stewardship Initiative (Photo credit: Radio-Canada/Camille Vernet https://ici.radio-canada.ca/recit-numerique/12610/ocean-oeufs-biodiversite-poissons-cb ). What is your interest in OA? Before starting my PhD, I didn’t have a background in OA, which shows that your research area can evolve as your interests develop. My research focuses on using ecological approaches to mitigate the effects of ocean acidification on salmon and herring, since CO 2  levels already reach well before end of century predictions in the coastal waters of British Columbia. In different times of year, salmon migrates in these challenging waters and herring spawn in these areas, which makes OA a pressing concern and highlights the need to find solutions which, for me, is by using ecology. Can you tell us about your past or current contributions to OA research? My first contribution to OA research was through a chum study where we found that high sensitivity to ocean acidification in wild out-migrating juvenile Pacific salmon is not impacted by feeding success. If you want to read more about it, it has been summarized here: https://www.oceanacidification.ca/post/new-paper-high-sensitivity-to-ocean-acidification-in-wild-out-migrating-juvenile-pacific-salmon-is . My upcoming paper is focusing on the potential of seaweed to mitigate OA effects in Pacific herring embryos. This forage fish spawns massively in the intertidal from February to May between Vancouver Island and Mainland BC. Through oceanographic processes, such as upwelling and tidal mixing, herring can be affected by ocean acidification. We hypothesized that seaweed, through photosynthesis, can help mitigate the negative effects of OA. I am also investigating whether intertidal air exposure provides a similar protective effect. These are two different ways ecology could be beneficial for herring development. Herring embryos on rockweed for my experiment on how seaweed could have the potential to mitigate ocean acidification effects. (Photo credit: Radio-Canada/Camille Vernet https://ici.radio-canada.ca/recit-numerique/12610/ocean-oeufs-biodiversite-poissons-cb ). What is the one take-home about OA that you wish all Canadians knew? I believe that one take-home message all Canadians need to remember is how pressing the OA issue is. By the end of the century, predictions indicate that a CO 2  increase of 800 µatm 1  will occur. In British Columbia, however, upwelling and tidal mixing already bring CO 2  levels beyond 1000 µatm 2  in some areas, exceeding end-of-century predictions! These levels may be temporary or short-lived right now, but their occurrence during salmon migration or during herring spawning season have the potential to impact the survival of these fish on the long term since some life stages are more sensitive than others.   What excites you most about the current or future of OA research in Canada? I am very excited to explore how ecology can shape these fish’s response to climate change. While some scientists prefer to remove any interactions in an experiment to isolate the direct effect of a variable, I believe that, in the wild, fish interact with the environment and that these influences should be considered, because it could significantly alter how they react to OA. To learn more about Virginie's work, please check out this ICI (CBC) article in French: https://ici.radio-canada.ca/recit-numerique/12610/ocean-oeufs-biodiversite-poissons-cb   References: 1: Feely, R.A., Sabine, C. L., Hernandez-Ayon, J. M., Ianson, D., and Hales, B. (2008). Evidence for upwelling of corrosive “acidified” water onto the continental shelf. Science, 320, 1490–1492. https://doi.org/10.1126/science.1155676 2: Evans, W., Pocock, K., Hare, A., Weekes, C., Hales, B., Jackson, J., Gurney-Smith, H., Mathis, J.T., Mathis, S.R. and Feely, R.A. (2019). Marine CO2 Patterns in the Northern Salish Sea. Frontiers Marine Science, 5, 536. https://doi.org/10.3389/fmars.2018.00536

Our August updates are here , featuring a new paper on OA impacts to juvenile Pacific salmon, dates for OA Week 2025, and more! View our updates here ! If you'd like to receive these updates, sign up for our membership at www.oceanacidification.ca/join-us !

Across Canada, salmon are one of the most valuable and culturally significant fisheries and aquaculture species. However, salmon populations are declining worldwide. Salmon are anadromous, meaning they migrate between fresh and marine waters as juveniles, with the variable and changing coastal conditions they must navigate presenting a challenge for survival. Climate change, ocean acidification, and the resulting changing ocean conditions along salmon migratory routes in areas like British Columbia are therefore a concern for long-term population stability. We interviewed Dr. Andrea Frommel, lead author of a new study that investigated how juvenile Pacific salmon are impacted by ocean acidification and changes in food availability and how these impacts can be identified in wild fish. Dr. Frommel is an Assistant Professor and Chair of Sustainable Aquaculture in the Faculty of Land and Food Systems at the University of British Columbia in Canada. Dr. Frommel has a BSc in Marine Biology, an MSc in Biological Oceanography, and a PhD in Fisheries Biology. She specializes in climate change impacts and environmental stressors in early life stages of commercial fish, as well as sustainable aquaculture. Dr. Andrea Frommel. Photo credit: Media team, UBC   For those of us not familiar with your area of research, could you give us a little bit of background on your research?   "I am looking at how additional stressors, such as ocean acidification and limited food availability, affect [Pacific salmon's] ability to successfully transition to life at sea." "I research how environmental stressors associated with climate change (ocean acidification, warming, hypoxia…) affect the physiology and development of early life stages of fish that are commercially important for fisheries and/or aquaculture. My current focus is on the locally important Pacific salmon and herring, as these species groups have unique life history strategies: Pacific salmon are anadromous and migrate from freshwater to seawater as juveniles, which is a physiologically challenging phase of their life and a bottleneck to survival for these species. I am looking at how additional stressors, such as ocean acidification and limited food availability, affect their ability to successfully transition to life at sea. Pacific herring, on the other hand, are benthic and intertidal spawners. This means that they attach their eggs to substrate, typically rocks or algae, and during low tide embryos are exposed to air for hours at a time. I am looking at how the substrate and air exposure can influence their tolerance to environmental challenges, such as hypoxia and ocean acidification."   What was the motivation or inspiration for this research? "We know that chum populations are currently doing very poorly for reasons not quite understood. Early marine life seems to be a bottleneck for some of the Pacific salmon species, as they have to migrate through an area with challenging ocean conditions, termed the Tidal Mixing Zone, to get to the open sea. These challenges include high carbon dioxide levels and low food supply, but how these conditions may affect juvenile chum was unknown. Previous research has shown carbon dioxide effects to be mitigated by high food supply. We had previously published two papers on ocean acidification effects in pink and chinook salmon, but had not included food as a co-varying factor. Also, chum are one of the Pacific salmon species to migrate out to sea at the smallest size and earliest age, making them potentially more vulnerable to these challenges. We devised an experiment to test the combined effects of ocean acidification and food availability on juvenile chum from this area." Juvenile chum salmon in an experimental tank. Photo credit: Andrea Frommel   What was the main question of this research? "The main question was, how do low feeding success and high carbon dioxide synergistically affect juvenile chum salmon during their natural migration to sea."   How did you go about answering your question? "We conducted the experiment at Hakai’s facility on Quadra Island, which is located right in the Tidal Mixing Zone. We caught wild chum salmon by boat, brought them back to the Marna Lab and exposed them to ocean acidification conditions for 3.5 weeks. A third of the fish were fed to satiation, a third at half that rate and a third were unfed. We expected to see an effect of ocean acidification on the condition and ionoregulatory ability in chum, but that these effects would disappear with ample food supply. Kristi Miller (DFO) had just developed fitchips for assessing transcriptomic responses to hypoxia and salinity challenges in chum and we teamed up with her to assess transcriptomic effects of carbon dioxide and food. These fitchips help determine the recent environmental stress history of a wild-caught fish through non-lethal gill clip sampling." The team dissecting fish for analyses - "truly a team effort!" Photo credit: Rumer Opie   What were the main findings of your work? "Our main findings were that chum salmon were highly sensitive to ocean acidification with 3 times higher mortality compared to the control. The main pathways that were affected were ionoregulatory genes, suggesting ionoregulatory failure in response to carbon dioxide. Feeding rate did not affect this high sensitivity and while mortality was unaffected by food deprivation, it did lower their condition and immune system." Figure 1 from Frommel et al., 2025 showing fish reared under high carbon dioxide (CO2) had 3x higher mortality than control fish.   Did you find anything unexpected? "Given that our previous experiments with pink and chinook salmon did not show high sensitivity to carbon dioxide, the high mortality in chum in response carbon dioxide was unexpected. Furthermore, many studies have suggested that the pathway of carbon dioxide stress is energy limitation – when fish have to expend a lot of energy regulating a respiratory acidosis in high carbon dioxide , this energy is not available for other important processes, such as osmoregulation, growth and development. Therefore, when fish are well-fed, they should be able to fuel those extra energy costs. However, our data suggests ionoregulatory failure, particularly in small individuals, regardless of food availability. Another surprising result was that we were able to detect a starvation signal in the gills, a tissue that is not usually associated with metabolic activity. Thus, fitchips are a useful tool to determine recent exposure to carbon dioxide and food in wild juvenile salmon." "Given that our previous experiments with pink and chinook salmon did not show high sensitivity to carbon dioxide, the high mortality in chum in response carbon dioxide was unexpected."   What is the one take-home of this work that you want everyone to know or remember? "One important take-away is that not all salmon are equal. This is the third species of Pacific salmon we’ve worked with and so far, all have shown unique responses to carbon dioxide . Additionally, juveniles are not just small adults. Their bodies respond to environmental stressors very differently than adult fish. To better manage and conserve Pacific salmon, we need to know species-specific and life stage specific responses to environmental conditions and focus management efforts on the vulnerable stages that are potential bottlenecks to survival." Dr. Frommel holding a juvenile chum salmon. Photo credit: Rumer Opie Read Frommel et al., 2025 here (open access): High sensitivity to ocean acidification in wild out-migrating juvenile Pacific salmon is not impacted by feeding success Citation:  Frommel. A. Y., Akbarzadeh A., Chalifoux, V., Ming, T. J., Collicutt, B., Rolheiser, K., Opie, R., Miller, K. M., Brauner, C. J., Hunt, B. P. V. 2025. High sensitivity to ocean acidification in wild out-migrating juvenile Pacific salmon is not impacted by feeding success. Ecological Applications. 35:e70058. https://doi.org/10.1002/eap.70058 To learn more about Dr. Frommel and her research, please visit: Frommel lab website Google Scholar Acknowledgements: Thanks to Dr. Andrea Frommel for taking the time to answer our questions and provide insight on this important new research.

Our July updates are here, including dates for OA Week 2025, Dungeness crab impacts, several recent Canadian studies, and OSM 2026 abstract calls ! View our updates here ! If you'd like to receive these updates, sign up for our membership at www.oceanacidification.ca/join-us !

Our latest poster on OA in Canada Species Impacts is here, featuring Dungeness crab ! Browse or download a high-resolution printable version and feel free to share widely! Poster text is provided below. Download our full-resolution, printable version: More about the OA in Canada Species Impacts Series: To summarize the current knowledge of OA impacts on species in Canada, the OA CoP has produced a poster series on how species are impacted by OA in Canada. The information presented here is based on the most current scientific literature (peer-reviewed, published papers) of studies conducted in Canada. We also highlight current gaps in our knowledge and areas that require additional research across Canada. These infographics are intended not only to highlight concerning OA impacts on important species in Canada, but are also meant to act as catalysts to support filling the gaps in our knowledge of OA impacts to species across Canada. Poster Text: OA in Canada Species Impacts: Dungeness crab Fast Facts: Scientific name: Metacarcinus magister Range: Pacific Canada and US Lifestyle: rocky-sandy seafloor, eats shellfish and other invertebrates BC’s most valuable fishery ($114M in 2023)1 Indigenous communities concerned about long-term commercial crabbing impacts OA Impacts in Canada (table): Overall Calcification Growth Survival/ Abundance Reproduction Physiological Larval ? ? ? ? N/A ? Juvenile ? ? ? ? N/A ? Adult ▼ ? ? ? ? ▼ Only 2 OA studies of Dungeness crabs conducted in Canada2,3 Only adult physiology has been studied in the lab, with negative impacts to acid-base regulation1 and olfactory (sensory) activity2 Several studies from the US report and model negative impacts of OA on Dungeness crabs across life stages4,5 Current Gaps: OA impacts to crab reproduction and survival? OA impacts to crab calcification and growth? Uncertainty in OA impacts to larval stages? Citations: https://www.dfo-mpo.gc.ca/stats/stats-eng.htm Hans et al. 2014. Mar. Biol. 161, 1179–1193. Durant et al. 2023. Glob. Chang. Biol. 29, 4126–4139. Bednaršek et al. 2020. Front. Mar. Sci. 8:651102. Alin et al. 2023. Oceanog. 36, 138 - 147. oceanacidification.ca

Our latest poster on OA in Canada Species Impacts is here, featuring the northern shrimp ! Browse or download a high-resolution printable version and feel free to share widely! Poster text is provided below. Download our full-resolution, printable version: More about the OA in Canada Species Impacts Series: To summarize the current knowledge of OA impacts on species in Canada, the OA CoP has produced a poster series on how species are impacted by OA in Canada. The information presented here is based on the most current scientific literature (peer-reviewed, published papers) of studies conducted in Canada. We also highlight current gaps in our knowledge and areas that require additional research across Canada. These infographics are intended not only to highlight concerning OA impacts on important species in Canada, but are also meant to act as catalysts to support filling the gaps in our knowledge of OA impacts to species across Canada. Poster Text: OA in Canada Species Impacts: northern shrimp Fast Facts: Scientific name: Pandalus borealis Range: Northern Atlantic and Pacific, Arctic Lifestyle: cold-water habitats (2 - 6oC), fast swimming, important zooplankton predator Canada’s 3rd most valuable  seafood species ( $312M  in 2023) after lobster and salmon1 and a closely monitored fishery in Canada OA Impacts in Canada (table): Overall Calcification Growth Survival/ Abundance Reproduction Physiological Larval ? ? ? ? N/A ? Juvenile ? ? ? ? N/A ? Adult ▼ ? ? ▼ ? ▼ Overall, northern shrimp are negatively impacted by OA  in Canada Only 3 OA studies2-4  on northern shrimp conducted in Canada Severity of OA impacts are region/population-dependent4 OA impacts made worse by hypoxia3 No impacts to nutritional value or taste2 Current Gaps: OA impacts to growth in Canada? OA impacts to early life stages in Canada? Regional differences in OA responses? Citations: https://www.dfo-mpo.gc.ca/stats/commercial/land-debarq/sea-maritimes/s2023pv-eng.htm Chemel et al. 2020. Front. Mar. Sci. 7, 1–13. Guscelli et al. 2023a. Jour. Exp. Bio. 226, jeb245400. Guscelli et al. 2023b. Front. Mar. Sci. 10, 1170451. oceanacidification.ca

Our March e-news updates are here, featuring an upcoming webinar from the GOA-ON Biology Working Group, a call for research papers on the environmental impacts of ocean alkalinity enhancement (OAE), and other new research. View our updates here ! If you'd like to receive these updates, sign up for our membership at www.oceanacidification.ca/join-us !

Our April e-news updates are here, featuring TWO(!) new databases for our community: and OA in Canada Experts and Publications database! View our updates here ! If you'd like to receive these updates, sign up for our membership at www.oceanacidification.ca/join-us !