Hi Chris, I was hoping someone else would give you some feedback on your nice series of thrush calls. Not only have I been talking too much lately but this topic can be a special quagmire.
I want to note that I have one monitoring station that is the first landfall directly southwest of the island of Newfoundland. Therefore, the flight calls of Gray-cheeked Thrush that I record there are very likely Catharus minimus minimus. They are consistently less humped and more descending than Catharus minimus aliciae. Their maximum frequency is 4 KHz or a little greater. I had another monitoring station that is the first landfall southwest of Cape Breton Island where Bicknell’s Thrush breed. These thrush calls have a maximum frequency over 5 kHz. I have attached a photo illustrating these three types of calls, including one from Louisiana provided by Bill Evans. Perhaps some of your calls are C.m.minimus. Given this race is believed to winter in South America, including Columbia, one cannot rule out the possibility of them flying over Etna, NY. It would be interesting to get a series of night flight calls from these two species in areas close to their breeding range. Thanks, John Kearney Carleton, NS From: bounce-120825839-28417...@list.cornell.edu [mailto:bounce-120825839-28417...@list.cornell.edu] On Behalf Of Christopher T. Tessaglia-Hymes Sent: September-26-16 08:15 To: NFC-L <nf...@list.cornell.edu> Subject: [nfc-l] Bicknell's Thrush - More Classic Example Albeit soft and slightly distant, this bird was recorded over Etna, NY on 23 September 2016 at 23:25. I would consider this to be a classic example because its peak frequency is above the 5kHz “safety” demarkation line. This bird peaks around 5.25 kHz and has an overall duration of about 250 milliseconds. Similar to the “possible Bicknell’s Thrush” examples posted yesterday, the sharp onset followed by a variably modulated and notably longer trailing descent is the call structure which caught my eye while browsing through my data last night. Attached are both the recorded call (with some lower cricket and noise bands gently filtered out) and a screen grab of the call for visual representation. Good night listening! Sincerely, Chris T-H -- Christopher T. Tessaglia-Hymes Field Applications Engineer Bioacoustics Research Program, Cornell Lab of Ornithology 159 Sapsucker Woods Road, Ithaca, New York 14850 W: <tel:607-254-2418> 607-254-2418 M: <tel:607-351-5740> 607-351-5740 F: <tel:607-254-1132> 607-254-1132 <http://www.birds.cornell.edu/brp> http://www.birds.cornell.edu/brp -- NFC-L List Info: <http://www.northeastbirding.com/NFC_WELCOME> Welcome and Basics <http://www.northeastbirding.com/NFC_RULES> Rules and Information <http://www.northeastbirding.com/NFC-L_SubscribeConfigurationLeave.htm> Subscribe, Configuration and Leave Archives: <http://www.mail-archive.com/nfc-l@cornell.edu/maillist.html> The Mail Archive <http://www.surfbirds.com/birdingmail/Group/NFC-L> Surfbirds <http://birdingonthe.net/mailinglists/NFCL.html> BirdingOnThe.Net Please submit your observations to <http://ebird.org/content/ebird/> eBird! -- -- 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://www.mail-archive.com/nfc-l@cornell.edu/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/ --
