Local Migration Analysis, New York City: Update, 11-12 September 2015, Tribute in Light Monitoring

Andrew Farnsworth The Cornell Lab Sep 12, 2015

BirdCast predicted a large movement of birds in the greater New York City area on 11-12 September: first, nearly a week has passed of summer-like conditions in the greater New York City metropolitan area, preventing most exodus of migrants that is typical under more favorable conditions; second, a moderate to heavy flight of birds occurred in the periphery of upstate New York and parts of New England last night, indicating a number of birds in the immediate vicinities of the New York City metropolitan area (the image above shows some of these movements, and you can visit our analysis to read more about these flights); and finally, and most important, conditions were favorable for migration this evening, with northerly winds, clear skies, and substantially cooler temperatures than the past week.

And the birds did, indeed, take flight. Migration was heavy in the immediate vicinity in an around New York City. Please return to this page, as we will be adding additional media to describe this epic flight.

The following are checklists of the birds recorded during the monitoring event. Some of these checklists contain rich media, such as photos and audio, others simply have descriptions of the event: Friday, 11 September, 8:00 pm EDTFriday, 11 September, 10:17 pm EDTFriday, 11 September, 11:05 pm EDTSaturday, 12 September, 12:58 am EDT, and Saturday, 12 September, 5:29 am EDT.

The following videos highlight the shear number of birds aloft in the beam reported in some of those checklists, and if you listen closely, you can hear flight calls of this massive attraction of migrants (most of the calls you can hear in the videos, where audible, are American Redstarts).

The following clip is shot looking straight up into the beams from the roof deck from which the lights originate. You can clearly see birds flying in all directions, and at a large range of altitudes above the beam (in fact, up to beyond the limit of optics!).

What’s particularly interesting about the following clip is the proximity of this migrant swarm to a nearby building that is under construction. At times during the event, large numbers of birds (several hundred in one scan), mostly warblers, were landing on the exposed metal and mesh of the portion of the building still under construction. Additionally, and most disturbing about the night, numerous birds crashed into the windows. We never saw any birds fall to the ground after striking windows, but we did see numerous individuals fly off dazed, either descending out of view around the building or landing on the building.

The following clip shows video through a Kowa TSN-884 spotting scope (this is not a petrie dish full of bacteria, these are primarily birds!). Although some insects are visible if you look carefully, most of what you see, and at high altitudes at that, are disoriented migrants flying in the Tribute in Light beams.

Despite the fact the so many migrants interacted with these powerful lights during this year’s memorial, the organizers and operators of the event were extremely helpful and acutely aware of the magnitude of the migration underway. As always, a very special thanks to the Municipal Arts Society for allowing NYC Audubon and the Cornell Lab of Ornithology to monitor at the Tribute in Light. Team BirdCast would like to acknowledge their efforts to turn off the beams to avoid potentially hazardous situations for birds. They shut off the beams EIGHT times during the course of the night, 20-minutes each, and each time after the lights had been extinguished birds stopped flight calling and departed from the area.