How many swallows does it take to create a radar image??
I just found out about a migratory event taking place in SE Yamhill County not far from our place. According to the Yamhill birder’s newsgroup, a scientist in B.C. alerted them to the radar signature of 70,000 to 100,000 swallows leaving their nighttime roost in a cornfield at around 6:10 am.
See below to be amazed! The swallows are the burst of green in backwards L-shaped Yamhill County, next to the I-5 marker. On the two mornings I have looked at it, they disperse slightly differently. Today, they veer SE and back NW before dispersing.
Just take a minute to imagine what this looks like from the ground! I am sorry to not be able to go there right now to witness the departure, or the evening return.
If you want to try this at home, go to the weather radar for this area, click “previous” to back up from the current time until you get to 6 a.m. on the clock (upper left of the map). Then you can click “animate” and watch it happen. Yikes