The North American West Coast is home to an underwater ocean highway – the California Current marine ecosystem (CCME), which extends from the southernmost tip of California up through Washington. Seasonal upward currents of cold, nutrient-rich water support a larger food web of krill, squid, fish, seabirds and marine mammals.
Climate change and subsequent changes in ocean pH, temperature and oxygen levels are altering the CCME – and not for the better. In a new study from McGill University, experts warn that over the next 80 years, climate impacts will significantly affect twelve economically and culturally important species that make their home in the CCME.
The region can expect to see substantial losses of kelp, red urchins, Dungeness crab and razor clams. In addition, habitat for anchovy and pink shrimp is expected to decline.
The results demonstrate how complex climate research can be. For example, while some environmental changes will result in benefits such as a higher metabolism and increased growth, other changes are severe, and could decrease survival rates.
Physiological increases in size or consumption are not always beneficial. This is especially the case when resources such as food and oxygenated water are limited.
Of all the climate effects modeled, ocean acidification was associated with the largest decreases in biological rates in some species, and the largest increases in others. This emphasizes how climate modeling is critical to safeguarding coastal ecosystems and the future of fisheries.
These impacts will likely have socio-economic consequences across the West Coast, but they will likely not affect everyone and every place equally. Since the area is highly productive, supporting fisheries and livelihoods for tens of millions of residents will require the ability to predict expected change across a range of species. This could shed light on potential economic impacts and optimal adaptive measures for the future.
“The time to accelerate science-based actions is now,” said study first author Professor Jennifer Sunday..“Integrating scientific information, predictive models and monitoring tools into local and regional decision-making can promote stewardship of marine resources and contribute to human wellbeing as we face inevitable changes in the marine life that sustains us.”
The study is published in the journal Global Change Biology.