With 15 species in one family, it was difficult to choose one to focus upon in the vireo clan. The first that I had ever clearly seen and photographed, Bell’s Vireo, will always have a special place in my birding guide, having studied its behavior for six years.
The family hosts strong, blue-legged individuals with stocky builds and hooked tipped bills with blunt ends. These are dull birds with non-descript markings, many of which enjoy dense foliage of willow and mesquite trees and bushes near a source of water. They fly to a chosen perch to sit for several seconds, though they move their bodies frequently in so doing.
The most interesting feature is the fact that the female builds a small cup nest in a horizontal fork, which could even be near the end of her tree or shrub. One would wonder how it stayed in its location, even after many years of inclement weather.
This sweet male bird usually sets up shop in the same general area from year to year and has an eclectic pattern of song that can be likened to “cheedle-cheedle-chew, cheedle-cheedle-chee,” which it continually repeats. It can usually be viewed well, as it generally sings from the tops of low trees and bushes up to a mid-canopy range.
It also is not odd for these birds to nest in the vicinity of the Warbling Vireo. Bell’s Vireo will continue to be declining and uncommon if it continues to lose brushy habitat, but writer has noticed a definite upswing in its population in Texas. Much of this can be attributed to healthy farming practices, where portions of the land are saved for wildlife to proliferate.
Bell’s Vireo has several races, which include the Eastern, Western, Arizona, and West Texas. The rarest is the Least or California subspecies. A noticeable characteristic of the Eastern subspecies is that it bobs its tail up and down, similar to the Palm Warbler. If one encounters a silent bird like a female or a juvenile, due to its plain countenance with just a single bright wingbar (and a faint upper bar), just those facts alone could well be enough to identify it. Its vireo bill should be enough to clinch what it is and is not, and a dull warbler or juvenile Verdin could be eliminated.
Our bright Eastern adults have a lovely yellow wash in fresh spring plumage with a thin, dark eyeline and pale bill. The drab adult is just that — even more non-descript.
Comparing the grayer Arizona subspecies with our Eastern, the Arizona is clearly a more shy bird, and sounds quite the same with no dialect to decipher. If you get the opportunity to photograph each race, it would be beneficial to do so, as chances are that future AOU judges may decide to separate the Least race. which has been highly victimized by the Brown-headed Cowbird and is endangered.
Keep your eyes on the ground and your head in the clouds. Happy birding!