Preston, While I’m certainly no expert on Bicknell’s calls, and likewise defer to others, I’ve definitely been paying attention to possible calls and I’ve been trying to tease apart possible characteristics more consistent with Bicknell’s versus Gray-cheeked.
I took a little time last night to manipulate your recordings to make them more audible – I had to increase amplitude by at least 15-20 times and added duplicate sound to the front end of the calls to give my brain time to adjust and to hear the call of interest. The first call, which peaked nicely around 5.3 kHz, I personally would have no hesitation in labeling as a Bicknell’s Thrush. Likewise, the second call, which peaks right around 5.1 kHz, I’d say has solid potential as a Bicknell’s Thrush. Echoing Matt’s comment, the very steep and sharp onset of the call is a characteristic I’m suspicious may be more reliably unique to Bicknell’s Thrushes. Similar to how Gray-cheeked Thrush calls can peak all over the place between 3 kHz and darned close to 5 kHz, there may be some acceptable Bicknell’s that are actually lower-frequency callers, below 5 kHz, and possibly identifiable simply by the structure of the call, rather than purely by the peak frequency – although high frequency is a dead ringer (if above 5 kHz) for Bicknell’s. Hope this helps, if at least somewhat…thoughts? Sincerely, Chris T-H On Oct 5, 2016, at 7:16 PM, Preston Lust <prestonl...@yahoo.com<mailto:prestonl...@yahoo.com>> wrote: 10/4-5/16, 8:00 PM-6:30 AM -- Yard, Westport CT While looking over recordings from this night, I came across two calls that appeared to me significantly higher and purer-toned than standard gray-cheeked calls. Both peak at around 5 kHz. The call at 2.55.46 is the highest of the two, and thus more likely Bicknell's. Am I correct in calling them BITH? Thank you for any assistance. Preston Lust, Westport CT -- NFC-L List Info: Welcome and Basics<http://www.northeastbirding.com/NFC_WELCOME> Rules and Information<http://www.northeastbirding.com/NFC_RULES> Subscribe, Configuration and Leave<http://www.northeastbirding.com/NFC-L_SubscribeConfigurationLeave.htm> Archives: The Mail Archive<http://firstname.lastname@example.org/maillist.html> Surfbirds<http://www.surfbirds.com/birdingmail/Group/NFC-L> BirdingOnThe.Net<http://birdingonthe.net/mailinglists/NFCL.html> Please submit your observations to eBird<http://ebird.org/content/ebird/>! -- <Thrush_2016-10-05_02.55.46_00.wav><Thrush_2016-10-05_05.03.36_00.wav> -- Christopher T. Tessaglia-Hymes Field Applications Engineer Bioacoustics Research Program, Cornell Lab of Ornithology 159 Sapsucker Woods Road, Ithaca, New York 14850 W: 607-254-2418<tel:607-254-2418> M: 607-351-5740<tel:607-351-5740> F: 607-254-1132<tel:607-254-1132> http://www.birds.cornell.edu/brp -- NFC-L List Info: http://www.NortheastBirding.com/NFC_WELCOME http://www.NortheastBirding.com/NFC_RULES http://www.NortheastBirding.com/NFC-L_SubscribeConfigurationLeave.htm ARCHIVES: 1) http://email@example.com/maillist.html 2) http://www.surfbirds.com/birdingmail/Group/NFC-L 3) http://birdingonthe.net/mailinglists/NFCL.html Please submit your observations to eBird: http://ebird.org/content/ebird/ --