Could glowing microbes be enticing ocean fish to snack on bits of plastic trash? That’s the intriguing idea floated here this week at the 2014 Ocean Sciences Meeting by researchers studying the “plastisphere”—the sea’s millions of tons of drifting synthetic detritus. “It’s a whole new ocean habitat created by humans,” says microbiologist Tracy Mincer of the Woods Hole Oceanographic Institution in Massachusetts. Past studies have shown that more than 1000 kinds of seagoing bacteria and other microbes can live on the plastic bits, which are often smaller than a fingernail. “Out there in the middle of the ocean, [microbes] are really looking for surfaces to glom on to,” Mincer says. But some colonizers do better than others, he reported. One big winner, according to a preliminary genetic analysis, are bacteria in the genus Vibrio—many of which are bio-luminescent. Indeed, researchers making night time trawls for plastic trash noted that up to 40% of their catch was glowing. And such shimmering refuse could be especially attractive to fish that hunt by sight, Mincer says. That could be bad for the fish, but good for the microbes, which can thrive in fish guts. “It’s a good gig for the bacteria—they have all the right genes to put a tap in that keg.”
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