Page 43 - The Black Range Naturalist Vol. 4, No. 3

are as distinct in the contact zone as they are in allopatry. The two singing types differ distinctly in mitochondrial DNA sequences and amplified fragment length polymorphism profiles. These results indicate that the two forms are reproductively isolated to a high degree where they co-occur and are therefore separate species.” ("Cryptic speciation in a Holarctic passerine revealed by genetic and bioacoustic analyses", David Toews and Darren E. Irwin, Molecular Ecology, June 2008, Vol 17, Issue 11, pp. 2691-2705.)
The best way to tell the two species apart is by song. The sonograms shown below are from the referenced study. Compare them with the YouTube video of a Pacific Wren and that of a Winter Wren (sorry about the ads).
The Marsh Wren, Cistothorus palustris, is also found in the Black Range. Although we are in the winter range of the species, they seem to be most common in passage - perhaps because we have so little “marsh”. They are found in relatively thick low undergrowth, such as reed beds.
The Bewick’s Wren, Thryomanes bewickii, is found, primarily, in the western United States and Mexico. Pronounce this species name like “Buick”. Photo Gallery. Video from Oregon and Hillsboro, New Mexico.
The Cactus Wren, Campylorhynchus brunneicapillus, is often found nesting in or near washes, generally in cholla or “thorny” plants. Photo Gallery. Video from Arizona.
The Northern House Wren, Troglodytes a. aedon, is the species/subspecies which we have in this area. On occasion a bird which looks like the Brown-throated Wren, T. a. brunneicollis, of northern Mexico and Arizona will show up. The main species/subspecies of South America is the Southern House Wren, T. (aedon) musculus. Although some “authorities” continue to assert (as do we) that the Southern House Wren, T. musculus is a species, the South American Classification Committee of the American Ornithologists’ Society now considers it a subspecies of the House Wren, T. aedon. Photo Gallery. Video from Wyoming. Video of Southern House Wren from Tobago for comparison (including song).
Of these species, the Canyon and Rock Wrens can be remarkably indifferent to nearby human activity. In Hillsboro, we sometimes encounter Canyon Wrens wandering about the yard, far from any
cliffs, looking in cracks and nooks for a bit to eat. They note your presence and go about their business. The song of the
Canyon Wren is one of the most beautiful bird songs which I have heard.
Wren, Cactus - Campylorhynchus brunneicapillus - Hillsboro, New Mexico
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