Saratoga Springs, New York

Black and white WarblerBird ID

Basic Warbler Watching


by Bill Thompson, III

Every year around September 1, a potent virus infects the minds of bird watchers.  The virus has become so common, so much a part of bird-watching culture, that it has achieved mythical status.  It is known as Confusing Fall Warbler Syndrome, or CFWS.

The primary sympton of CFWS is a desire to throw up one's hands in dismay anytime one sees a warbler in fall.  CFWS leads one to think that warblers are tough enough in spring (when they're dressed in their breeding finery and singing), so in fall (when they are drab, quiet little green and yellow birds) identifying them is hopeless.  The good news is that while the symptoms are real, CFWS itself is mostly a myth.  Warblers in fall are only marginally more difficult than warblers in spring.

A CHECKLIST
First, decide if what you're looking at is a warbler.  This is not hard most of the time.  The only real area of confusion involves the vireos, which tend to be plain greenish birds.  In general, vireos are less colorful, slower moving, and have larger bills than warblers.  When you do find a bird that you don't recognize immediately, work your way quickly through a mental checklist.  Do this before you look at the book!  The bird may fly away before you get another look, but the book will always be there.

Start at the head and work back.  Check the head and face pattern for cap, eye lines, and color.  Face pattern is often critical in identifying similar species.

Check for wing bars.  Warblers break down into two broad groups, those with wing bars and those without.  Noting whether the bird has wing bars will cut the number of birds under consideration in half.

Check the underparts.  Are there streaks or a breast band?  If the bird has yellow below, does it go all the way to the tail, or is it just on the chest?  If you can see the back, check for streaks or other patterns.  It is difficult to see the backs of warblers because they spend so much time near the treetops.  Fortunately, the back pattern is rarely a key character.

Check the tail.  Many bird watchers forget to check the tails of warblers.  Some warbler species can be easily recognized by their bright yellow or white tail spots.  A few species flash white outer tail feathers.  The palm warbler wags it tail as it forages, often on the ground.

Check the undertail coverts, which are the feathers that cover the underside of the tail; usually, they extend about halfway out the length of the tail.  Checking undertail coverts may seem a bit over-technical to many people, but it is often a snap because a lot of warblers are seen only from below.

It takes only a few seconds to run through this checklist, and it can be the difference between identifying a bird and letting it get away.  After using it a couple of times, it becomes second nature, and you can identify every warbler you see.