This morning I had a group of 5 Pine Siskins land in one of my Sycamore trees. It's their first visit to my yard this year. The hot March in 2012 followed by freezing temperatures in April led to an almost complete seed crop failure in my trees last year. The seed balls that are normally the size of a golfball were stunted down to the size of a dime. The outlook is much better this year.
In 2008 and 2009 I also had siskins visit my yard in May and in both of those years the returned for a couple of days in mid to late June.