Barn Swallows on radar

Researchers have found a way to use radar for tracking bird movements. I learned just a few days ago that the large flock of Barn Swallows that gathers for roosting in cornfields every fall here in Yamhill County, Oregon, is showing up on NEXRAD images when they take off in the mornings from their nighttime roost. In the image above, the large green cluster shows the flock as it began to spread out this morning at 6:42 a.m. The following images indicated that most of the birds apparently disperse to the east, which would place them mostly in Marion and Clackamas counties, at least for the early part of the day. They return to their chosen cornfield at about 8:00 p.m., but do not seem to show up very well on radar at that time.