My interpretation of the situation described by Andrew Rush is that the characteristics of Pacific-slope birds occur in varying frequency and combination throughout an extensive portion of the range of Cordilleran Flycatcher, whereas the characteristics of Cordilleran birds are relatively rare and geographically restricted within the range of Pacific-slope Flycatcher. This means that an out of range bird showing characteristics of Pacific-slope Flycatcher cannot be identified confidently as such, because all of the characters indicative of Pacific-slope (genetic, vocal, and morphological) occur at significant frequency within some populations of Cordilleran. Conversely, an out of range bird with a consistent suite of Cordilleran traits would be less likely (but still possibly) derived from a Pacific-slope population (e.g., circa Mt. Shasta).
Shai Mitra Bay Shore ________________________________ It's International Education Week... Celebrate at CSI<http://www.csi.cuny.edu/international/events/education_week.html> -- NYSbirds-L List Info: http://www.NortheastBirding.com/NYSbirdsWELCOME http://www.NortheastBirding.com/NYSbirdsRULES http://www.NortheastBirding.com/NYSbirdsSubscribeConfigurationLeave.htm ARCHIVES: 1) http://www.mail-archive.com/nysbirds-l@cornell.edu/maillist.html 2) http://www.surfbirds.com/birdingmail/Group/NYSBirds-L 3) http://birdingonthe.net/mailinglists/NYSB.html Please submit your observations to eBird: http://ebird.org/content/ebird/ --
