The best way to improve any bird identification guide is to rip out pages. You won’t need most of them.
Imagine how a new birder feels when opening a book to the warblers, only to find four dozen possibilities. The warblers are all the same size and shape. They come in a wide variety of hues and patterns, with a confusing tendency toward yellow. The choice is daunting, like trying to pick one culprit from a police lineup of 50 suspects.
The problem is that every warbler on every page appears to be equal in likelihood to all the other warblers.
Over the years, field guides have tried to make the task easier. My bookshelf is lined with unused and unusable books that tried to break the selection into smaller groups, based on color or habitat. It was a nice try, but no answer. Birds change color and change habitat, frustrating the attempt.
The solution is to customize your guide to your current location. Wherever you stand in the country, there is a long list of birds that are not there. Tear out those pages. Field guides cover a wide geographical area. Even the smaller pocket guides cover half the country. If only there was a guide for the precise spot where you are standing, eliminating all the birds that are not likely to be there. The range of possibilities would shrink to a more manageable number, making identification vastly easier.
So let’s tear out the pages. We can discard the warblers that aren’t likely to be found in Maine and reduce the identification possibilities down to a couple of dozen. Then, let’s rearrange these pages to suit the exact spot where we are standing. The most likely warblers would be at the top of the pile; the least likely would go to the bottom.
For instance, if we can’t see a pine tree from where we are standing, we’ll put pine warblers at the bottom. If we’re among roadside shrubs, we’ll put common yellowthroats near the top. If we’re in the middle of the forest and can’t see a bush anywhere, yellowthroats go to the bottom.
Of course, experienced birders don’t actually tear out the pages. They just mentally rearrange them. On a casual walk through a hardwood forest, black-throated green warblers move toward the top of the list, vying with the northern parula for supremacy. If the trail wanders into a birch and beech grove, black-throated blue warblers move up. Throw in a lot of balsam fir and some sunny edges, and the list is topped by magnolia and Nashville warblers. Emerge from the forest into a glade of saplings, and bump American redstarts and chestnut-sided warblers to the top. Stroll the riparian area of a meandering stream, and a yellow warbler teeters high on the list of probabilities.
Now that you’ve got the hang of it, expect black-and-white warblers among sparse forest trees of medium height. Step into a more mature forest, especially with pines and hemlocks, and shuffle the Blackburnian warblers upward in the deck. Brush by a bog, and palm warblers creep toward the top. Go north and search among thickets of spruce. If it’s dry, blackpolls and bay-breasted warblers become more likely. If it’s wet, Wilson’s warblers are good candidates.
Once these habitat clues become ingrained, you’ll start to suspect certain warblers before you even see them. Make predictions. Amaze your friends! Start with your own backyard. Get to know the warblers of your neighborhood. Note the trees they prefer. The same birds will be in the same habitats wherever you go in Maine. Do the same thing when you go upta-camp. Study your favorite hiking path. The warblers become downright foreseeable.
Now, let’s start taping the pages back into the book. You may need them after all. We are in the heart of migration season. Birds wander out of range, sometimes overshooting their southern breeding territories. Once you know what’s expected, the unexpected grabs your attention.
On June 5, 10 years ago, a cerulean warbler spent the morning in an oak above my log cabin, singing merrily, unaware that he had flown 300 miles past any likely mate. Worm-eating, Kentucky, yellow-throated and hooded warblers sometimes wander into the state in spring.
These strays won’t stay.
In two weeks, most of the migration will be over, and all the breeding warblers will be exactly where they are supposed to be. And you can rip out the unneeded pages again until autumn.
Bob Duchesne serves as vice president of Maine Audubon’s Penobscot Valley Chapter. Bob developed the Maine Birding Trail, with information at mainebirdingtrail.com. Bob can be reached at duchesne@midmaine.com.