Fall migration birding is a quite different beast from spring.
Spring migration brings a glorious burst of song and color as millions of tiny feathered gems pour northward, singing their hearts out, flitting with excitement of getting to breeding grounds. They are much easier to spot and identify in the spring, by song and bright plumage. The challenge of spring birding is finding all the species, but once found, most are easy to identify.
In the fall, birding is much more difficult—and for some, that makes it all the more fun!
Come the fall, birds are driven by survival to get to warmer climes. If they want to eat, they need to go where the insects are—and insects do not thrive in cold temperatures.
So the males molt their bright plumages, needing fresh feathers for the long flight home. Most retain some color, but generally, they are duller and more similar to the females and, in some cases, species look quite like others.
In particular, the silence of fall migration adds several degrees of difficulty. In the fall, birds don’t sing—at the most, you hear an occasional call. These calls are far more subtle than the songs, and most don’t even call. They just emit little chipping sounds. Researchers actually record these chips that birds make in flight and have learned to distinguish among the species, primarily though sonographic analysis. Listen here.
If you’re interested in the challenge of fall birding, keep reading for some tips on when and where to go.
The internet is the obvious place to start—it offers a range of astonishing data that can help birders determine when to rush out to the park and when to get a few more minutes of sleep. Of course, birders know from experience and from other birders where the local hotspots are, but how do you know if the birds are headed that way, and when?
You call the FAA, of course! Well, not quite. But you do check the radar. Sid Gautreaux was a ground-breaker in 1963 when he began to study bird migration using weather radar. The work at world-famous Radar Ornithology Lab at Clemson University continues to this day, but radar-based birding predictions are now available to birders on a variety of websites covering different regions.
Here in the mid-Atlantic, I rely on David LaPuma, a post-doc at New Jersey Audubon, who runs woodcreeper.com. At 5:45am, I fire up the laptop and wait for David to post his summary of the night’s radar images, weather and wind patterns.
But hi-tech devices can only go so far. While radar can confirm where the birds have been in recent hours, which tells the birder the magnitude and direction of the migration over the past night, you need weather predictions to forecast when the big flights will occur.
So, the next step is to hold your finger to the wind. A big cold front will stop birds from moving south. The low pressure associated with a cold front brings southerly winds and storms. Birds wait it out, storing fuel, and when the front clears, and a tail wind comes from the north, a big gush of birds pours south.
Waiting 200-300 miles south are the eager birders, arriving shortly after dawn. On days like these, the skies are dripping with birds. Dozens of pairs of eyes can’t keep up with them; sorting through them to find the few unusual species is a great challenge that takes quite a lot of time and patience. For those of us who have to head off to work, it can be excruciating to hear about the great birds that popped out after we left. (Which is why we buy lottery tickets. Those retired guys—they can go out every day of the week and stay as long as they like. Retiring is also a great birding strategy.)
It’s almost over, by the way. Here in the mid-Atlantic, the warblers will be past Maryland by mid-October. A few species will come through in late October, and a couple even stay year-round.
These spatial and temporal patterns are now recorded not just in the scribbled notebooks and scraps of paper kept in birders’ back pockets. Dedicated birders send this information to eBird at the Cornell Lab of Ornithology, where the thousands of observations can be retrieved by birders and scientists alike.
And as the song goes: “They’ve got the urge for going now, and they’ve got the wings to go.”
Birders are getting ready for semi-hibernation. Yes, there is birding to be done in the winter, and we will.
(Image: Red-eyed vireo. Source: Tim Boucher.)
Tags: Audubon, bird call, bird song, Birding, Clemson University, Cornell Lab of Ornithology, David LaPuma, eBird, fall birding, migration, Radar Ornithology Lab, Sid Gautreaux, songbird, vireo, warbler, winter birding