It's a natural part of his plumage, Gail.... won't hurt him a bit!
I think lighting is a problem here, Gail..The dark area behind the eye in this image doesn't show the same colour but it's the same, normal plumage. Basically same spot just different lighting.... sunny side/shaded side... just look at the shadow. He's just fine!!
Google: Dog Tick, Wood Tick and Black-legged Tick so you will recognize them and how they look. It's no only Black-legged Tick that can make you ill, even though Black-legged Tick is the one that carries the possibility of Lyme disease.
Thanks, Joanne. Very helpful as always :)