Friday, October 11, 2013

Winter Wren

The diminutive, somber-plumaged Winter Wren, like this one I banded this week, is awash in scientific controversy. I previously blogged about Winter Wrens currently being considered three species—the eastern Winter Wren and the western Pacific Wren, plus another species in the Old World.

In Europe and Asia, at least 44 races are described. DNA research indicates that, in the Old World, at least four groups exist, possibly containing several distinct species. The groups reside in Europe, eastern Asia, Nepal, and in the Caucasus. The potential, new species within these groups are said to be cryptic—you can only identify them with a DNA laboratory in your field vest.

Winter Wren races have different habitat preferences. North American birds breed in coniferous, boreal old-growth forests. Clear-cutting and forest fragmentation have reduced the numbers of North American Winter Wrens. European Winter Wrens breed in deciduous woodlands and in urban parks and gardens. In North Africa, these wrens are limited to forested streams at elevations of 1200 to 1800 meters. In the Himalayas, they are found to 4575 meters (Handbook of the Birds of the World Alive).

All this is confusing enough, but DNA work also indicates that Winter Wrens are more closely related to Cistothorus, a genus of Old World warblers, than they are to other wrens—even other wrens that currently share the Winter Wren’s genus, Troglodytes. Many ornithologists now argue, using both DNA evidence and other morphological data, that Winter Wrens should put in a separate genus, Nannus (Hejl et al. 2002). I do not believe, however, that anyone is suggesting that these birds are not wrens.

Finally, DNA studies suggest that wrens, traditionally listed near dippers and mimc thrushes, are actually closer to treecreepers, gnatcatchers, and nuthatches. I don’t know about you, but all this confusion finds me beginning to recite Shakespeare ("a rose by any other name would smell as sweet").

No comments:

Post a Comment