Visual evidence

A study conducted from 2010 to 2019 shows that whales off the coast of California are consuming microplastics at alarming rates. Microplastics are tiny bits of plastic debris. The study revealed that the whales often consume food at between 50 and 250 meters below the surface, where the amount of microplastics is the highest. And how much plastic they consumed wasn't just affected by depth—it also mattered what kind of food they ate. For example, blue whales feed almost entirely on krill. Krill also consume microplastics from the water, so any whale eating krill will ingest even more plastic. The scientists estimate that a blue whale probably consumes about 10 million microplastics a day. By contrast, whales that eat fish will ingest less plastic, because fish don't tend to consume microplastics.