we live in northern NM. Our dogs have small brown bugs that are attaching themselvs to their skin. Belly, rear and other areas. They are about the size of a flea, but more not as flat and more streamlined. They do not attach in next to each other, they almost spread apart in a pattern. I have even found a couple around our ferrets mouth also. We can pull them off, but they do not react to flea or tick lotion. What are these?