Any walk through deciduous woods when the leaves are out drives home the importance of knowing what birds sound like. It can be a lesson in futility to try to find a tiny warbler at the top of a giant oak tree covered in leaves. The exercise can lead to frustration and a condition known as “warbler neck.”

My birding-by-ear skills are average at best, and I was reminded of this during a recent walk through the woods under a thick canopy. I heard several warblers and other birds, and, while I saw only a few, I was able to recognize the songs of several others. There were many birds, however, I could not find through my binoculars nor recognize by their songs or calls. As I mentioned before, it can be frustrating, but I have reached an age where I can let go of the frustration quickly and not dwell on the bird that got away. In years past, I would often hold onto the frustration long after the walk, which, after all, is supposed to be enjoyable.

Birds don’t always look exactly like they do in a field guide, whether the images are photos or illustrations. There are different plumages depending on time of year, age, sex and other factors. There is also slight variation among individuals of a species. Not every male robin looks exactly the same.

That said, birds don’t always sound exactly like they are supposed to either. A bird’s song is only one of the sounds they make and even their songs can vary greatly. Cardinals, for instance, have distinctive high-pitched call notes. They also have a distinctive song, but there are several versions of the song. The cardinal in your forsythia may have a song that is greatly different from the cardinal across the street. All of the songs are loud, clear and beautiful, but very different. Don’t get stuck thinking that the cardinal song you hear every day is the only one cardinals have. Many other birds are the same way as well.

My advice if you are just starting to learn bird sounds is to learn the common and obvious ones really well. Study what the robin sounds like. Their typical song is often translated to “cheerily, cheer up, cheer up, cheerily, cheer up.” But there is much variation in the song, and they have several calls as well, such as the “tut, tut, tut,” call.

Robins are very common in New England, so if you learn the sounds of the robin, you can save yourself much frustration on your walks by not getting hung up on a bird you will likely come across several times.

Get to know the various calls and songs of blue jays, cardinals, nuthatches, chickadees and titmice. You will hear those often throughout the year, and you can eliminate other birds in the spring when you hear those sounds during a song-filled spring morning.

Warblers and other migrants are a different story. We do not hear them year-round, but rather for only a few weeks out of the year. That is a short window to try to learn those songs in the field. Birding Internet sites and phone apps are filled with recordings of bird songs and calls. I would encourage you to learn a few warbler songs each year so as to not try to pack too much information in your head and end up not remembering anything. Learn the yellow warbler and common yellowthroat, for instance, as those are commonly heard in the spring and summer throughout New England.

Warblers are difficult to learn because there are so many of them and many of their songs are similar to each other’s. But, as I said, learn a few a year and within a couple of years you will be picking out many of the songs you hear in the woods in April and May. And if you just can’t pick it up, don’t fret or stress. Study a little more, and get it next time.