For the generations that watched Finding Nemo, perhaps not surprisingly, the west coast of North America has its own version of an underwater ocean highway, the California Current Marine Ecosystem (CCME). The CCME stretches from the southernmost tip of California through Washington. Seasonal updrafts of cold, nutrient-rich water are the foundation of a larger food web of krill, squid, fish, seabirds and marine mammals. However, climate change and subsequent changes in ocean pH, temperature, and oxygen levels are changing the CCME—and not for the better.
A new study led by McGill University Biology Professor Jennifer Sunday and Professor Terry Klinger of the University of Washington’s EarthLab Ocean Acidification Center warns that climate impacts will significantly affect twelve economically and culturally important species living in the CCME over the next year. 80 years old. The northern part of this region and areas closer to shore will be the most responsive to changing ocean conditions in this setting. Significant loss of canopy-forming kelp, reduced survival rates of red urchins, Dungeness crab and clams, and loss of aerobic habitat for anchovies and pink shrimp can be expected in the region.
The impact of climate change is complex
Estimating the biological effects of several environmental variables at once shows the complexity of climate sensitivity studies. For example, while some expected changes in the environment will increase metabolism and increase intake and growth, concomitant changes in other variables or even the same variables could potentially decrease survival rates. Notably, physiological increases (eg, in size, intake, or motility) are not always beneficial, especially when resources—such as food and oxygenated water—are limited.
Of all the climate effects modeled, ocean acidification was associated with the largest declines in individual biological performance in some species, but the largest increases in others. This result highlights the need for continued research and monitoring to provide accurate, actionable information.
Modeling is critical to protecting coastal ecosystems and the future of fisheries
Investing in predictive models and implementing adaptation strategies will become increasingly important to protect our ecosystems, coastal cultures and local livelihoods. Similar challenges will be faced by species not addressed in this study, and responses will be complicated by the emergence of invasive species, disease outbreaks, and future changes in nutrient availability.
These sensitive species will likely have socio-economic impacts that will be felt throughout the West Coast, but they will likely not affect everyone and every place equally. Because this area is highly productive, supporting fisheries and livelihoods for tens of millions of West Coast residents, the ability to predict population-level changes for a number of species that may be affected should shed light on potential economic impacts and optimal adaptation of measures for the future.
“The time has come to accelerate science-based action,” says Jennifer Sunday, an assistant professor in McGill’s biology department and first author of the paper. It echoes the messages of the recent UN Ocean Conference 2022 and its associated WOAC parallel event. “Integrating scientific information, predictive models and monitoring tools into local and regional decision-making can help manage marine resources and promote human well-being as we face inevitable changes in the marine life that sustains us.”