Fowl ticks prefer to hide in cracks and crevices like Eggcessive mentioned. I recommend that you tear apart areas in your hen house that are dark (corners) and/or moist/or rotting boards/debris, use a flashlight. Check the area where your bitten hen perches for the night.
Bulge below earlobe - Page 2
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We have found NO more ticks in the coop or run, or on any other bird. :)
I contacted our local extension office, and a vet there told me that ticks inject an anticoagulant, and that this was probably a large bruise.
I agree! It makes sense!
She looks so much better now. I'd say, back to what she looks like in the first picture I posted here.