Warning: This topic is not for the faint of heart. If you find yourself scratching your head while reading this post, it won't be for lack of understanding. Having survived a bout of head lice with my children, the mere mention of the word conjures up waves of obsessive itching. I hasten to note that -- according to my research -- poultry lice do not infest humans. Whew! (Pausing to scratch the back of my neck, nonetheless).

If you are a dedicated chicken keeper, you'll understand me when I say that I was inspecting my girls' backsides for evidence of diarrhea when I noticed about 5 strange-looking crusty cone-shaped structures near Babs' vent. Thinking they were new feathers gone awry, I pulled them out and then noticed several very tiny straw-colored bugs scattering across her skin toward her belly. I parted the feathers and was horrified to discover a favela of lice feasting on dead skin cells and feather parts! I promptly released the hen and ran inside to my computer. I discovered that Babs has chicken body lice and here is what I found courtesy of the University of California (source: http://ucanr.org/freepubs/docs/8162.pdf):

• Chicken body lice do not infest humans. They are present on the skin and feathers of the chicken and can be transmitted from one bird to another when roosting or nesting close together. Their eggs (nits) are found in clusters around the base of feathers, usually in the sparsely-feathered area beneath the vent.
  

• Eggs take 4-7 days to hatch and 10-15 days to mature to adult-hood, therefore re-treatment 7-10 days is necessary.
• The chicken body louse spends its entire life-cycle on the bird, therefore it's not necessary to go crazy with disinfecting the entire property.
• My chickens could have contracted the lice from new birds brought into the flock, wild birds, or rodents. Chickens should be inspected regularly (twice/month) for the presence of egg clusters or adult lice, both of which are typically found by parting the feathers on the abdomen below the vent. Lice also hang out in the wing-pits and on the head. They are more of a problem in the cooler months of the year.

I am following a sensible procedure for managing this parasite that is a compilation of advice I received and found on various websites, as follows:

• Clean out the chicken hutches by removing all poop and bedding and spraying down with water. I may also spray the interior with a dilute bleach/water solution. This should be done at least weekly.
• Regularly sprinkle the chicken yard with food grade diatomaceous earth (DE), focusing on the areas where they dust themselves (identified by the presence of bowl-shaped depressions in dry soil). DE is a flour-like product which is fossilized skeletons of microscopic aquatic organisms. It kills lice and mites by damaging the insects' exoskeletons. I will use a mask and goggles for personal protection when sprinkling the DE. If it rains, I will need to re-apply as DE doesn't work if it's wet.
• For each chicken, inspect them for the presence of egg clusters. Remove them, if possible, and seal them in a ziplock bag and dispose.
• Dust each chicken with poultry dust (available at most feed stores) or a Sevin-5 powder, which can be purchased at any hardware or garden store. Repeat dusting in 7-10 days.

A note on dusting . . . some people recommend placing the chicken, up to its head, in a plastic bag containing the dust and then "shake & bake". Can you imagine how difficult it would be to get the chicken in the bag, let alone everything else you'd have to overcome with this procedure? I found it easy to pick up the chicken, hold her legs in one hand and support her back with the other. Gently lay her down on a flat surface on her back and pull the legs upward and toward you just so her knees are straight (helps her stop fighting to right herself). Most chickens will open their wings in this position, which is very helpful. Librally sprinkle the poultry dust or Sevin-5 on the rump, abdomen, and wing-pits. Use your fingers to massage the dust between the feathers so it reaches the skin. Gently fold the chickens wings against her body and roll her over holding her legs and breast in one hand and her folded wings and back with the other. Place her on the ground and she's done. Be sure to wear a dust mask when dusting the chickens.

Happy chicken dusting!

UPDATE: 10 days after dusting, I am pleased to report that the live bugs are all gone. I am going to dust the girls again today as a follow-up to catch any bugs that are just hatching, as the lice eggs (nits) are unaffected by the Sevin-5.