New research from West Coast oceanographers provides insight into the cause of toxic algae blooms that caused shellfish closures and marine mammal deaths near the Oregon-California border.
The study, published in the journal Frontiers in Climate, shows climate change and a 2013-2015 Pacific Ocean heatwave, often called “the blob,” have together increased the growth of toxic algae off the coastline from Cape Mendocino, California to Cape Blanco, Oregon.
“The 2015 warm anomaly populated or seeded this new site, which now is a new source of toxin to contaminate shellfish on our coast,” said Dr. Vera Trainer, a research oceanographer at NOAA’s Northwest Fisheries Science Center and the study’s lead author.
After 2015, there were persistent clam and crab closures on the Northern California and Southern Oregon coast, Trainer said. The research confirmed the warm water temperatures seeded algae that were protected from ocean currents and stored in sediment at this new hotspot off of Trinidad, California.