Carpodacus mexicanus

It's time to clean the seed feeder. In the last couple of days, I have seen a few females with inflamed eyes. It's a strain of the bacteria Mycoplasma gallisepticum, and causes the conjunctive tissue around their eyes to swell. Their eyes can swell enough that they cannot open them at all (rendering them vulnerable to starvation and predators). Normally, they go through the feeder in about two days, and when it gets close to empty, I bring it in and clean it with dilute bleach. I doubt it helps much to prevent the spread of the eye disease, but it has to be better than nothing.
 
In the early spring, I was seeing perhaps 30% of the House Finches affected, although I am sure the statistics are inflated towards infected birds, which tend to congregate around the feeder because it's easy picking. In the late spring and early summer, the problem seemed to disappear, so I was disappointed to see this poor bird affected.