Hello! This very well could be lice. Lice are commonly found in sparsely feathered areas, such as below the vent and under the wings. Lice leave scabs on the skin and masses of eggs at the base of small feathers. Since these eggs hatch fast and two lice can easily turn into way more, it is important to efficiently manage this problem. Also, if one chicken has lice, chances are others do too, so make sure to check the rest of your chickens for lice. Make sure to provide proper nutrition to your flock, as well as regularly cleaning their coop. If you find that multiple chickens in your flock have lice, you can try treating the whole flock, but a lot of times the only successful way of eliminating these parasites is treating chickens individually. Start by going to your local
tractor supply store and looking through their poultry anti-parasitic medications and treatments. Good luck, and feel free to PM me with any questions.
-Ameraucanas