The Bird Call Blog by Greg Harber, September 2015
The past several weeks I have been searching downtown Birmingham for Chimney Swift roosts. You may recall that last year a chimney located at 4th Avenue North and 17th Street North hosted several thousand swifts (5,000 was our highest estimate) at the peak of their migration. However, this year I have yet to see even one swift utilize that chimney. We were able to obtain some drone images of that chimney and it is clear of any obstructions, so why they are not using it remains a mystery to me.
This year I have located a couple of sites that hosts 200-300 swifts at one, and 400-500 swifts at the other. Early this evening I returned to the top of the parking deck at 5th Avenue North and 17th Street North with my binoculars to scan the skyline in hopes of being able to see another swift roost site. Last year’s roost was still a bust, but as I walked the top level of the deck I looked northward toward the BJCC and could see two large swirling masses of birds. One was the tight writhing ball of a murmuration of starlings, the second was a much looser #swiftnado – at last, swifts in large numbers!
I quickly descended to street level and pedaled to the Boutwell Auditorium parking deck, to the immediate west of the facility itself. In the last of the fading light I estimated 2500-3000 swifts swirling above the chimney at the rear (north end)
of the auditorium, immediately adjacent to the I-20/59 lanes of traffic. The interstate lighting illuminated the chimney well enough so that even as darkness fell hard I could see birds entering the chimney. I would estimate that 1500 birds entered while I was watching, with another 1000 circling as darkness enveloped the skies overhead. The good news is that the deck is located immediately adjacent to the auditorium and the chimney is only about 40 yards away – very close!
Peculiarly, as I watched I could see a number of birds flying OUT of the chimney and away into the darkness. Since it was completely dark I could not track where these birds were headed, but it was obvious that the last batch of 1000 or so birds did not enter the chimney. It seemed as though the swirling mass of swifts was late entering the roost, based on past experience at other sites, so I don’t know if that played a role in the birds finding enough room in the chimney shaft once they entered. What happened to those 1000 birds I have no idea. I plan to return to the roost site tomorrow evening and see if the numbers persist, or if the same scenario prevails again tomorrow night. Google Maps indicates that the chimney runs the entire height of the building so room ought not be a problem, I would think.
Next weekend is another Swift Night Out survey period and Birmingham Audubon will once again participate in counting swifts. I plan to do the two sites I had previously located on Friday and Sunday nights, but will likely survey this new Boutwell site for our September 12th Saturday night destination. We will meet at the Fish Market Restaurant on Birmingham’s Southside at 5:30 p.m. for a Dutch Treat dinner and then depart for the Boutwell Parking Deck by 6:30. Consult the Birmingham Audubon web site for details: Swifts Night Out Event.
On a related note, last Thursday while on a group bike ride that went to George Ward Park on Green Springs Highway we observed 40-50 Common Nighthawks flying above the lights of the ball fields there, and on the return route back to the Redemptive Cycles shop we observed another 10-12 birds above the UAB ball field on University Boulevard. Friday night I took a swing past UAB’s Jefferson Tower and there were multiple birds flying there shortly after sunset.
And maybe best of all, the past several nights I have been treated to the silhouette of a Yellow-crowned Night-Heron as it feeds along the edge of the waterfall pool at Railroad Park. It doesn’t need the waterfall lights to see its prey, of course, but the changing light palette does make for a striking scene as the birds stands silent and still amidst the rippling waters.
Take care all, Greg
Learn more about Chimney Swifts at ChimneySwifts.org.