Date: 6/5/18 7:35 pm From: Fran M <franmmmk...> [ILbirds] <ILbirds-noreply...> Subject: IBET 2300 Chimney Swifts in Hyde Park - Saturday 6.2.18
This past Saturday, June 2nd, I spent a few hours in Hyde Park, and had dinner at dusk at The Promontory restaurant, 5311 S. Lake Ave W. The food here is excellent; we sat on the patio, and after a few minutes I noticed Chimney Swifts circling across the street. I observed for close to an hour, and took 14 videos between 7:49 pm and 8:35 pm. I estimated the counts of swifts entering the chimney by slowing down each video and counting the birds per minute, and then extrapolating for the time I was there. The 2300 is a conservative estimate. Below is one of the 14 videos (iPhone); I have another with more birds entering, however, the audio includes the server calling them sparrows, and then bats, and then claiming he's a beginning birder.....anyway, this is a less distracting 25 second video, although not as comical:
On 10/20/2009, I counted 3340 swifts entering a chimney behind the Evanston Police Station. In this instance, I had a scope focused on the chimney entrance and was able to count by 10's the number of swifts entering. If you've never seen this behavior, it's pretty amazing. It seems the birds gather until they have a decent number, then begin swirling, and on some queue, they drop in. Other times they circle, but none of them drop in. Once a group is in, more birds gather and the process begins again. The exception seems to be that the "really late" birds just show up and go right in, almost like they know they're late.