I observed a similar phenomenon a few weeks ago. For the span of about an hour, there were lots of grackles moving through my neighborhood. I watched them in my back yard, and my neighbor's back yards as well. At times I would see around 30-50 birds, then they would thin out a bit, and then there would be another bunch moving through. They were moving from south to north in Keywaydin Meadows on the east side of Foothills Parkway in Boulder. I didn't see them feeding on anything, just moving through. I don't know if there were hundreds of birds, or if they were looping around and coming through several different times. Since they all seemed to be moving in the same direction, I suspect it was a large flock moving through in one direction. I almost expected to hear the soundtrack from "The Birds" playing in the background.
A few minutes ago, I looked out the window and saw the neighbor's tree full of grackles again. There were around 50 in this flock, but they quickly moved on and there haven't been any more yet. They were moving from south to north again, at this particular location anyway. Jeff Parks Boulder, CO -- You received this message because you are subscribed to the Google Groups "Colorado Birds" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/cobirds/17befa24-9828-42a6-9917-3d82c07f4ec7%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
