Anchovies are known more as a pickled pizza topping than for their crucial place in the marine food chain.
(From National Geographic / by Laura Parker) — Now scientists have confirmed a disturbing new behavior by these tiny forage fish that could have larger implications for human health: anchovies are eating tiny pieces of ocean plastic, and because they, in turn, are eaten by larger fish, the toxins in those microplastics could be transferred to fish consumed by humans.
Anchovies are mistaking microplastics for food because it smells like food, according to a new study in the science journal Proceedings of the Royal Society B. The findings are among two new studies examining the impact of microplastics on the marine environment published this week. The other study, which appears in the journal Science Advances, explains, in part, how microplastics are transported to the deep ocean by tiny marine invertebrates known as giant larvaceans.
Microplastics are created when larger plastic debris breaks down by sunlight and wave action into rice-sized bits that measure five millimeters or less. They have turned the world’s oceans into what scientists call a “plastic soup,” but their impact on the marine ecosystem is not fully understood. A 2015 study that attempted to measure how much microplastic is in the world’s oceans confirmed the “soup” description, when it estimated the number of particles in 2014 ranged from 15 to 51 trillion pieces, weighing between 93,000 and 236,000 metric tons.
But other questions remain. Among them: How long does it take for plastic to degrade in the ocean and what happens to its toxins as that breakdown occurs? Some 700 species eat plastic, but the impact of that is still under investigation.
The body of research is growing rapidly. When Matthew Savoca, a post-doctoral researcher at the National Oceanic and Atmospheric Administration Southwest Fisheries Science Center in Monterey, California, began his anchovy study, 50 species of fish had been documented eating microplastics. When his research concluded two years later, the count had doubled to 100 species of fish.
“The scientific interest in this problem has absolutely exploded in the last five years,” Savoca says. “In the public eye, there is this idea that all the plastic out there is large pieces that we can identify. Toothbrushes, cigarette lighters, plastic bags. But the vast majority of ocean plastics are these small fragments. More than 90 percent are less than 10 millimeters long. It’s really small stuff.”
Read the full story here: http://news.nationalgeographic.com/2017/08/ocean-life-eats-plastic-larvaceans-anchovy-environment/