@jeanwilson - it was so gross. I got a couple pounds of turkey feathers from the farm. Mind you, it's a game farm, so those birds live good lives.
CONTENT WARNING: REALLY GROSS BIRD MITES. Billions of bird mites.
I made two key mistakes: 1. asking for "as many of them as I could get" (specifying that I could only use the first three primary flight feathers from each wing). and 2. asking for them right before Thanksgiving (but in my defense I was buying a free-range heritage turkey from them, and thought it would save a trip all the way out there).
Apparently they gave me ALL the feathers from ALL the turkeys they had processed for ALL their customers in Northern Minnesota. For Thanksgiving. So do you know how many feathers are in "a couple pounds"? It's a lot of feathers. An overwhelming number of feathers. Way too many for me to deal with right away - especially since they were dirty, and especially as it was going to be Thanksgiving, and I had holiday things to do.
They were in a big plastic bag (but not clean, because they had shortly before been on living turkeys running free on a game farm). So I put them down in my basement until I could deal with them after the holidays. You know - one thing lead to another. My in-laws came for a long weekend; my kids were still really little; I was really busy at work.... So the feathers stayed in the bag in the basement, until one of my kids was down there looking for something a few weeks later and asked me if the birds in the bag were okay. I told him they're just feathers, but he said, no, there are birds in there. because it. was. moving.
OMG you could see the feathers shaking in there as billions of microscopic bird mites proliferated and feasted on them. So I did what any self-respecting person would do. I snuck them out to the garage before my spouse could see and hid them behind the lawn mower. And then I took a very hot shower while screaming inwardly.
When I went to pull the lawn mower out in the spring, there weren't any more feathers on the feathers. Just bare shafts and some...dust. So I put them in a bucket in my basement, and tried not to think about them too much, as I tried to work up the nerve to deal with them. Okay, maybe a reasonable person would have thrown them away. But I paid money for them, and I didn't want to believe that they were a total loss.
Later, much later, I discovered that the shafts were clear and hard, because they had been sitting there, drying out and curing. I cut one without tempering it, and it turned out great. We strip off the feathers for writing anyway, so silver lining, I guess.
And that is my bird mite story. Moral of the story: Wash those feathers as soon as you get them.