So many pine siskins have been feeding here since late fall and many appear to have succumbed to that lung disease wild birds can contract called aspergillosis which is caused by a fungus found in decaying matter.
I should probably stop putting out niger seed for a while because those feeders are the ones they congregate the most at. But, they should be moving north very soon to breed. In fact, many have probably already left my area and I am now seeing ones which were staying south of me. I have found at least 15 dead siskins in the last few months but most have been found this month.