Microplastic ingestion by baleen whales: How big a threat are the smallest plastics to the largest animals?

Baleen whales may be at extreme risk of exposure to microplastics, but neither the amount nor pathway of microplastic ingestion are well understood. My colleagues and I combined data from the California Current Ecosystem on density of micro plastics at different depths with tag deployments on blue, fin, and humpback whales to measure plastic ingestion rates and routes of exposure. We found that per day, a krill-feeding blue whale may ingest 10 million pieces of microplastic, while a krill-feeding humpback whale likely ingests one million pieces of microplastic.  Register now!