Barn Swallow flock on Doppler radar

The green "burst" just above the word "Woodburn" on the map above was recorded this morning at about 6:25 a.m. The flock of Barn Swallows that is spending every night roosting in cornfields just to the west of the burst (across the Willamette River in Yamhill Co.) apparently begins every day by heading east, but at 7:30 p.m. they can be seen returning to the cornfield from every point of the compass. (Clicking on the image above will make it easier to see that the flock is airborne between Newberg and Woodburn at 6:25.)




This evening I tried again without much success to video the swallows that gather here before they head to South America for the winter. I estimate that there are several hundred thousand swallows here, but the video captures only a very small portion of the near edge of the huge flock.

Barn Swallow flock staging in Oregon

Once again the huge flock of Barn Swallows (which forms every year at this time here in Yamhill County, Oregon) is staging a repeat performance. Current thinking is that this gathering likely represents a significant percentage of the Barn Swallow population of northwestern North America. It's impossible to count so many birds spread over several square miles, but when they come together in a "hurricane" swirl over a large cornfield, and then take an hour to plunge down into it to find a nighttime roost, it becomes obvious that there are several hundred thousand birds involved, and perhaps more than that. The photo shows only a small section of the entire flock, but gives some idea of the spectacle that is repeated here nightly for about a month every fall. (Click on the photo for an enlarged view.)