Interesting calls Tayler. If your 3-call cut is unedited then it sounds like multiple birds may be involved. The calls don't sound like Western Meadowlark or Bobolink, and they don't fit the flight call descriptions of Black-headed Grosbeak or Western Tanager in Sibley. Bullock's Oriole might be a possibility but your calls are shorter than typical for that species, and in my experience orioles rarely give nocturnal flight calls.
It is tough with the weak recording but the species that rings closest for me is House Finch. Not sure how that possibility might fit at your recording site (?) in Washington State, but it is now thought that all finches are sometimes involved with night movements in the east, especially in coastal areas. I look forward to following your detective work on the identity of these calls and to hearing what others think. Bill Evans Danby, NY ----- Original Message ----- From: Tayler Brooks To: nfc-l@cornell.edu Sent: Saturday, August 29, 2009 2:41 AM Subject: [nfc-l] Black-headed Grosbeak NFCs and ID help Hello all, I'd like to hear from those out there that have experience with the nocturnal flight calls of BHGR. How different are they from those of Rose-breasted Grosbeak? I set up my equipment for a night of recording in Brier, WA yesterday. At around the 1:30am mark, some interesting flight calls showed up on the spectrogram. Three FCs were recorded that I initially thought could be those of a Bobolink, as they were somewhat brief (79, 65, and 42 ms long), beginning at 2.8 and ending at 3.8 kHz (generally), were all rising in pitch, and showed a complete parallel upper band on two of the calls (the first only had half of one). BHGR was suggested as an ID for the mystery sound, can they give fairly short, ascending flight calls differing from the usually monotonal (or slightly descending), longer FCs of RBGR? Here's a spectrogram of my recording, the call is about 65 ms (compared here to some spects of BOBO from the Evans and O'Brien program): http://tinyurl.com/np2r7n The sound file itself can be heard here (intervals shortened): http://tinyurl.com/kto4zc The recording is very faint, is it beyond being identifiable? I've had some pretty decent flights over my yard this month with 297 flight calls recorded on the 18th and 329 last night, basic species breakdowns and spectrograms will be posted to the list soon! Thanks for the help and good birding, -Tayler Brooks from Washington -- NFC-L List Info: http://www.NortheastBirding.com/NFC_WELCOME http://www.NortheastBirding.com/NFC_RULES http://www.mail-archive.com/nfc-l@cornell.edu/maillist.html --