White on neck... Mites?

[chickenlife01]

Noticed one of my favorite hen has these white bug looking things on her neck. Are they mites? I have dusted them all with DE as a precaution and she's the only one I notice that has them. Is there any thing else I should do? Thanks!

 

[Judy]

This shows what to look for and tells how to treat.

http://ohioline.osu.edu/vme-fact/0018.html