Daytime and nighttime temperatures are inching downward now, and that means fall migration is picking up. The sagging cold front from earlier this week no doubt has ushered in some neotropical migrants. They have been trickling through for a few weeks now but in generally undetectable numbers. I expect this weekend it will become easier to find these tiny travelers as numbers build.
Birders know to find chickadee and titmouse flocks when looking for fall migrants. Warblers, flycatchers and vireos in particular seek these flocks out. The chickadees and titmice are very vocal, quick to give alarm calls when a threat is determined. It’s the safety-in-numbers thing. Right now, there may only one or two individuals mixed in but in a few weeks the migrants will outnumber the hosts.
When I am in the field I immediately listen for and head right to a chickadee call once I determine where it is coming from. If the flock is moving fast, I might try to intercept it at a favorable viewing spot such as a clearing or field edge. I then filter out the constant chickadee noise, listening for faint chips, zeets and zips that give away the presence of a warbler or two. That’s the easy part. I am fortunate that time hasn’t eroded my hearing, yet. Now I must locate the bird.
Combine the dense foliage and a fast-moving flock and there is a real identification challenge. Experienced birders can in an instant sort through the chickadees and titmice, however. Subtle differences in shape and size will give away the warblers and vireos. Maybe that bird looks a little chunkier. Maybe it’s shorter tailed. Maybe it’s larger, or smaller. Perhaps it is a little more nervous acting, or maybe it is more laid back. All of these slight variations can cause a birder to zero in on a particular individual. These are helpful even when the birds are seen in silhouette instead of in full sun.
So, this weekend I will be looking for uncommon goodies such as cerulean warblers, blue-winged warblers, Canada warblers, least flycatchers and more. There will be some around, but it’s a right place, right time situation. Some area birder will find something really nice, I expect.
I’ll report next week on how my birding went. I will be in the field most of the weekend.
Taylor Piephoff is a naturalist with an interest in the birds and wildlife of the southern Piedmont: PiephoffT@aol.com.