Common Grackles with Injured or Infected Legs/Talons/Feet/Claws

I've had a lot of grackles the past month or so and notice a few with things wrong with their legs or talons. One was missing the entire leg nearly. Another had a closed/clinched talon that doesn't open (saw some time ago) and the one recent one I've been noticing is one that has a completely swollen talon on his left foot, about three times the size of the other unaffected talon of his. It looks really bad. He doesn't put any weight on it either. I've tried to google some info on this and it might be Avian Pox. If I could capture him I would and send him to a wildlife rehabber. I'm not sure how curable or treatable Avian Pox is. I've also noticed two more House Finches with House Finch Disease. I sent one finch off with it to a wildlife rehabber last week, but not sure I'll be able to capture any of these birds unless they're within reach and not moving much like what happened with the House Finch I took to the rehabber.