Spring Bird Migration Underway

Posted on: April 26th, 2017 by Leslie_Zucker

Are you won­der­ing when you’ll hear the sweet song of the yel­low war­bler again? Check out the like­ly arrival date of your favorite feath­ered inhab­i­tant of the Ashokan water­shed at Cor­nel­l’s Bird­Cast web­page. (Yel­low war­blers are just begin­ning to return from their win­ter homes to breed in forests of the North­east!) If you real­ly want to keep track of things, you can watch radar.

Accord­ing to Audubon edu­ca­tor Lar­ry Fed­er­man, we can keep track of bird migra­tion by going to the Nation­al Weath­er Ser­vice website’s radar page and use the “Com­pos­ite Loop” fea­ture. If you look on less rainy evenings, you’ll see blue cir­cu­lar “blobs” expand­ing – that’s the radar echoes of migrat­ing birds!


Lar­ry advis­es that the best time for radar obser­va­tions is just after dark – our song­birds migrate at night so folks can see the blue cir­cu­lar forms widen and move to the north as night pro­gress­es. Also, if you are inclined, go out­side and lis­ten for flight calls of the migrat­ing birds!

To view migrat­ing birds “in per­son”, the best time is at first light. The birds will be most active as they for­age for food to replen­ish what they’ve used up dur­ing the evening’s flight. Peo­ple should look for bud­ding trees and flow­ers that attract insects – that’s what the birds will be look­ing for.

In addi­tion to radar, new tech­nolo­gies such as tiny geolo­ca­tors are allow­ing researchers to track bird movements.


On this NEXRAD radar image from May 1, 2016, the bright green and yel­low swirls rep­re­sent pre­cip­i­ta­tion in storms and the blue blobs, clus­tered along the Gulf and Atlantic coasts, are most­ly large num­bers of migra­to­ry birds. Image cour­tesy of the Bird­Cast project, whose work in the Gulf of Mex­i­co region is fund­ed by the South­ern Com­pa­ny and Nation­al Fish and Wildlife Foundation.