I keep it by the coop in a food bucket. I sprinkled some DE on top and 2 days later it looks like they're all dead. Now I need to check the grain bag that it came from!
I don't see spots. They just look black to the naked eye. In the photo though they look like they're speckled. I sprinkled diatomaceous earth in the feed yesterday and seem to have a lot fewer of them this morning. I hope it works.
I found hundreds of these tiny critters in my chicken feed. They're a third the size of a grain of rice. They look like ticks, but are they? In San Diego, 100 degree weather, the scratch is in a sealed bucket.