We know plastic can stay around in the environment for hundreds of years, if not longer. When it gets old, it breaks into tiny pieces that some animals end up mistaking for food. What have we seen? Lots of garbage. Just about any time the nets come up there are a few pieces of plastic inside. That is just what we see. Many pieces of plastic are too small to detect with our eyes. We can be certain this has some effect on the environment we are studying.