From jmorlan@ccsf.cc.ca.us Fri Feb 14 12:57:50 1997 Date: Fri, 14 Feb 1997 12:57:50 -0800 (PST) From: Joseph Morlan <jmorlan@ccsf.cc.ca.us> To: birdwg01@listserv.arizona.edu Subject: Cordilleran Flycatcher redux The recent thread on Cordilleran Flycatchers was originally started based on some observations by Jennifer Matkin and myself in the Warner Mountains in July. Unfortunately we were away from access to BIRDWG01 during most of January, but have obtained all the messages from the archives. These messages were quite helpful, but leave certain questions unanswered. Also I have some personal correspondence on this subject from Ned Johnson and Jennifer has corresponded with Dick Cannings which sheds some light on the problem. I was particularly interested in Louis Bevier's discovery of typical Cordilleran male position notes (MPN) on the east side of the Warners. Our observations were on both sides of the Warners but primarily at the summit of Cedar Pass where we camped and spent considerable time studying a pair of Western Flycatchers. The male never gave the distinctly two-parted call which Bevier and Marantz reported from the east side. Furthermore Johnson (in litt) stated that birds in the Warners "rarely give" the distinctly two parted call. The calls we heard were actually of three different types. The most common MPN was a very slightly two-parted sharp "pseeet" (Johnson terms this "steeply rising). It also seemed to give the same call without the almost inaudible first part. Thus a single high sharp "seeeet." This bird also gave the lower, fuller, upslurred (Johnson calls it sinusoidal) call "suwheeet" typical of Pacific-slope Flycatcher. The sinusoidal calls were given more frequently in the late afternoon and early morning. Johnson (in litt) states that these vocalizations are all typical of Cordilleran Flycatcher in this region. The implications of this have been touched upon, but I'm not sure they have been clearly articulated in prior discussion. Many Cordilleran Flycatchers from the western part of their breeding range do not give the distinctive two-parted call note of birds from further east. In particular, migrants giving the typical sinusoidal call of Pacific-slope Flycatchers might actually be Cordilleran Flycatchers. Such birds would almost certainly be misidentified by most birders using current field criteria. In sum, migrants giving typical Cordilleran MPNs can be confidently identified as Cordilleran, but those giving typical Pacific-slope MPNs could be either one. Johnson (in litt to Cannings) has stated that the best distinction is the SONG. The song is three parted in both species as described by Chris Benesch. However Johnson describes the distinction quite differently from Benesch. According to Johnson, it is the third part of the song that differs consistently between the species. This part may consist of two or three syllables. One must consider only the two accented notes if the section is three parted. On Pacific-slope the sequence of the two accented notes is low-high (sounds like "pittick" to me) and on Cordilleran it is high-low. Notice that this approach pretty much eliminates the so-called "intermediate" song types. I have not yet had a chance to visit the breeding grounds early enough in the season to test this difference in song and would like to learn what others think about it. Does anybody have any recordings they can check? One other question remains unresolved in my mind. Although it is clear that Cordilleran may give Pacific-slope MPNs as well as the high thin "pseet" or "seet," I wonder if the reverse is true. Can Pacific-slope Flycatchers give a single steeply rising "pseet" or "seet" as a MPN. I can give a partial answer. I recall that Pacific-slope Flycatchers on Santa Cruz Island gave both calls. This goes along with Johnson's view that the Island race is somewhat similar to Cordilleran. But I simply cannot recall Pacific-slope Flycatchers elsewhere giving this call as a MPN. I'm pretty sure I've heard it incorporated into some Pacific-slope songs though. Any further comments would be most welcome. ---------- Joe Morlan "The benefits to wildlife of a San Francisco, CA human-free environment outweigh jmorlan@ccsf.cc.ca.us the costs of radiation." ('SF Chronicle' analysis of Chernobyl) http://cloud.ccsf.cc.ca.us/Continuing_Education/ornith.html