Cleaning out some coops and my son noticed these bugs in the wet dirt (had a lot of rain lately). They don't get off of the dirt unless knocked off, not even when I held the clump of dirt in my hand of a while (so not seeking heat or anything like I thought a blood sucking mite would). Does anyone know what they are? The whitish colored ones on the clump seem to be youngsters. I knocked a few of the brownish red ones off on to the white paper. Thanks for any help.