I saw a bird nest once that the bird had lined with shredded bits of plastic bag to reinforce it.

Unfortunately, most people are so completely brainwashed that they feel proud of themselves for putting their plastic in the (open topped) recycling bin where it blows out, goes down the drain and ends up in the sea. They imagine that putting it in normal (closed top) rubbish will cause it to end up in a seagull's stomach, starving it to death while "recycling" allows them to sit back and gloat about how lucky they are to have the opportunity to save the planet.