dmark@sunybcs.uucp (David Mark) (03/20/88)
Thanks, John Shipman, for interesting birding notes, especially the ones on SW New Mexico. I will be birding in Arizona and New Mexico in a couple of weeks, and will try to find some of those birds! John also wrote: >Taxonomic note: I have heard rumors of possible splits in two >species, Black-tailed Gnatcatcher and Brown Towhee. In both >cases, the California forms are reputed to be distinct. Anybody >heard anything concrete? >-- >John Shipman/Zoological Data Processing/Socorro, New Mexico >USENET: ihnp4!lanl!unm-la!unmvax!nmtsun!john The February 1988 issue of _The Condor_ (v. 90, no. 1) contains an article by Robert M. Zink entitled: "Evolution of Brown Towhees: Allozymes, Morphometrics and Species Limits" (pp. 72-82). Zink concludes: "Therefore, I advocate species status for _crissalis_ (California Towhee) and _fuscus_ (Brown Towhee)." (p. 80). The California Towhee's range is west of the Salton Sea / Impreial Valley. If _fuscus_ occurs in California, it would along the Colorado River only. Taxonomic wrok based on electrophoresis is controversial. However, in this case, the AOU Check-List (6th Edition) already noted that a split was suggested "Because of differences in vocalizations and morphology" (p. 685), so I suspect this split will eventually become 'official'. The split of the gnatcatcher into _P. californica_ (Black-tailed Gnatcatcher) and _P. melanura_ (Plumbeous Gnatcatcher) is mentioned as a possibility in the 6th AOU (p. 544). The _californica_ group is resident in chapparel from LA county south. The Plumbeous Gnatcatcher is in SE California (north to southern Inyo Co.) east to s and w Texas and way south into Mexico. Talk suggests this split to be very likely. I have also heard that the Brewer's Sparrow may be split, into the northern Rockies subalpine form and the Great Basin sage-brush breeders. Western Flycatcher may be split into a coast-range and a Rockies form. Maybe someday I'll write the article: "Birding on the Taxonomic Future's Market"! David Mark dmark@joey.cs.buffalo.edu or geodmm@ubvms.BITNET