Thursday, May 24, 2012

The Treetop Vocalist

Over the past month, loud vreeeps have echoed through our neighborhood on my morning walks to work. Their source is always difficult to locate but these clear, ascending calls seem to arise from the treetops, where the vocalists remain hidden amidst the dense foliage of late spring.

In fact, they are the distinctive calls of great crested flycatchers, colorful insectivores that prefer to hunt in the upper canopy of open, deciduous woodlands; suburbs of the central and eastern U.S. thus appeal to these summer residents. Nesting in tree cavities, great crested flycatchers utilize a wide variety of nesting materials, including human trash and discarded snakeskins; it is only during the collection of these items that they are likely to be seen on the ground and, even then, they fly from site to site, not hopping or walking like most songbirds. The great majority of their time is spent in the trees, snaring insects from leaves and stems or catching them in mid air.

By late summer, great crested flycatchers begin to migrate toward their wintering grounds in the Caribbean, Central America and northern South America. There they feast on insects in the canopy of rain forests and, unlike most migrant songbirds, remain vocal throughout the year.