For many of us, vireos are just voices in the treetops. These small, insect-eating birds spend a lot of their time feeding high in the trees, where their songs are the only clue to their presence. Add to this their green coloration and leaf-shape, and you have the recipe for a hard-to-see bird.

Four species are regularly seen in our area of the Carolinas, with an additional two species being migrants, although the Warbling does have a toe-hold as a breeding species in extreme northwestern North Carolina. The four are Blue-headed, Yellow-throated, Red-eyed and White-eyed vireos. Each bird has its own niche, but knowing their songs is often the key to finding these birds.

To see (or hear) vireos, it is best to take a quiet walk along a forest path. Stop often and listen to the birdsong emanating from the treetops. The song of all three forest species is superficially the same, but each has its own character. The Red-eyed is the most common and its persistent, repetitive phrases can be heard even during the heat of the day. The Blue-headed Vireos song is similar but sweeter, and the gaps between the phrases are longer. It prefers higher elevations, often within spruce-fir or northern hardwoods forest.

Our last forest species is the Yellow-throated Vireo. His song is like a shortened version of the previous two species, but with a burry quality, and has been likened to the words three-eight given time after time.

The White-eyed Vireo differs from the others by being found in brushy thickets and tangles, often around water. The song, which seems to say Quick, gimme a beer, quick, is quite different to that of the forest species and is easy to learn by the distinctive chik note at the beginning and end of each phrase.

Our remaining two vireos are the Warbling and the Philadelphia, and both are found in the Western Carolinas mainly during spring and fall migration. The Philadelphia somewhat resembles the Red-eyed, but with a softer facial expression and yellowish underparts. The Warbling is a quite different, fairly nondescript brown bird, but the best singer with its distinctive finch-like warble.

While I must admit vireo identification by voice is not easy for beginners, it is by far the best way to recognize the presence of these birds in your area.

Simon Thompson has lived in WNC for the past 16 years. He owns and operates his own birding tour company, Ventures Birding Tours. www.birdventures.com.

If you have birding questions, please drop Simon an e-mail at the above site.