Species Shift

I have noted a change in some of the visitors to our feeders this winter: one of our most common year-round birds, House Finches, have almost completely disappeared. Another common winter visitor, White-crowned Sparrows, have also gone missing. Their places appear to have been taken by large numbers of American Tree Sparrows, who rarely showed up in previous years.
 

Most of our other usual winter birds are here however, like this Junco, waiting with one of the American Tree Sparrows for a turn at the feeder during last Sunday's snow storm.

Here's a dual portrait of our missing friends taken in March 2009.