For the generations that grew up watching Find Nemo, it is perhaps not surprising that the North American West Coast has its own version of the underwater ocean highway – the California Current Marine Ecosystem (CCME). The CCME stretches from the southern tip of California all the way up to Washington. Seasonal upwelling currents of cold, nutrient-rich water form the backbone of a larger food web of krill, squid, fish, seabirds, and marine mammals. However, climate change and the resulting changes in ocean pH, temperature and oxygen levels are altering the CCME — and not in a good way.
New research led by McGill University professor of biology Jennifer Sunday and Professor Terrie Klinger of the Washington Ocean Acidification Center at the University of Washington’s EarthLab warn that the impacts of climate change are affecting 12 economically and culturally important species living in the ocean CCME have their home will be significantly affected in the next 80 years. The northern part of this region and areas closer to the coast will be most sensitive to changing sea conditions within this environment. The region can expect a significant loss of canopy-forming seaweed, declining survival rates of red sea urchins, Dungeness crabs and razor clams, and a loss of aerobic habitat for anchovies and pink shrimp.
The effects of climate change are complex
Assessing the biological impacts of multiple environmental variables simultaneously demonstrates the complexity of climate sensitivity research. For example, while some anticipated environmental changes boost metabolism and increase consumption and growth, concomitant changes in other variables, or even the same, could potentially reduce survival rates. In particular, physiological increases (eg, in size, consumption, or agility) are not always beneficial, especially when resources—such as food and oxygen-rich water—are limited.
Of all climate effects modeled, ocean acidification was associated with the largest decreases in individual biological rates for some species, but the largest increases for others. This finding underscores the need for continued research and monitoring to provide accurate, actionable information.
Modeling critical to protecting coastal ecosystems and the future of fisheries
Investing in predictive models and implementing adaptation strategies is becoming increasingly important to protect our ecosystems, coastal cultures and local livelihoods. Species not addressed in this study will face similar challenges, and responses will be complicated by the arrival of invasive species, disease outbreaks, and future changes in nutrient supplies.
These species sensitivities will likely have socioeconomic consequences that will be felt across the West Coast, but they will likely not affect everyone and every location equally. Because the 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 range of species likely to be affected should shed light on potential economic impacts and optimal adaptation measures for the future.
“Now is the time to accelerate science-based action,” says Jennifer Sunday, an assistant professor in McGill’s biology department and first author of the paper. She reiterates the messages from the recent UN Ocean Conference 2022 and related WOAC side event. “Integrating scientific information, predictive models and monitoring tools into local and regional decision-making can enhance marine resource stewardship and contribute to human well-being as we face inevitable changes in the marine life that feeds us.”