It turns out that fish are also helpless victims of smokers. No joke, as reported by Jeffrey Kluger for TIME:
For smokers, the world has always been one big ashtray, with cigarettes flicked away pretty much anywhere. That’s especially true now, since smokers are increasingly forbidden to light up in restaurants, office buildings and even new no-smoking condos. In the great river of litter human beings create each year, so tiny a thing as a cigarette butt hardly seems to amount to much. But with the world’s smokers burning through a breathtaking 5.6 trillion cigarettes per year — 4.5 trillion of which are simply tossed away outside after they’re smoked — little things add up fast. That, as it turns out, can be especially dangerous for one type of nonhuman critter: fish.
About a third of all of the trash found on U.S. shorelines consists of cigarette butts.