Alright, so I'm newer to chickens. I started with chicks and they still aren't laying yet. We recently cleaned out their tractor and removed the duck, which has helped keep it cleaner (removing the duck I mean). I was letting them out this morning and pet one then noticed a bunch of tiny worm like things crawling on my hand. They were small and dark and definately moving! What are they, are they harmful? How do I get rid of them?