Re: [nfc-l] Nocturnal flight calls, Colorado's Front Range, 3+ years of data
Hi all, Andrew brings up an interesting question about midsummer nocturnal flight calls. As he suggests, I think there are a variety of different behaviors going on here. In the case of cuckoos, their midsummer nocturnal flight calls usually seem to be associated with good breeding habitat, suggesting that these are local breeders, not birds on the move. I know at least in New Jersey and Maryland where Black-billed Cuckoo is much scarcer than Yellow-billed, there are certain spots where I can go and listen at night and predictably hear Black-billed Cuckoo calling overhead. In the case of rails (King, Clapper, Virginia, Black, Sora, and Moorhen, at least, all give nocturnal flight calls in midsummer) my sense is that these are birds searching for ephemeral breeding habitats – maybe listening for frogs or other rails as they fly over. I could see Nelson's Sparrow or other marsh birds doing the same thing. Other non-marsh-birds may be doing the same sort of thing too. If a Grasshopper Sparrow’s field gets mowed, it needs to go find another one, and the safest time to do that would be at night. Then there is molt migration like the Chipping Sparrows in Colorado. Although relatively few species seem to do such a large-scale molt migration, a small percentage of many species do seem to move a moderate distance to molt while the bulk of the population stays to molt closer to the breeding grounds. Bobolink is a good example – small numbers regularly appear at coastal stopover sites from as early as late June before the large-scale migratory push appears in mid-late August. A number of warblers do the same thing, like the handful of Yellow-rumped Warblers that appear annually in Cape May in mid-August (and then vanish – lying low while they molt, I guess) before the rest of them arrive in October. best, Michael O’Brien - Original Message - From: "Andrew Farnsworth" To: "Ted Floyd" Cc: NFC-L@cornell.edu Sent: Thursday, July 29, 2010 8:36:27 AM Subject: Re: [nfc-l] Nocturnal flight calls, Colorado's Front Range, 3+ years of data Hello all, Ted, I congratulate you on another excellent and timely post. Regarding our attention to details: a couple of thoughts. . .apologies for hijacking the thread a little! Molt migration is a fascinating phenomenon, and many, myself included, are still eager to see a larger scale effort to monitor this behavior (in particular the nocturnal movements by acoustic monitoring). Has anyone on the list operated acoustic monitoring stations in the intermountain and mountain western US - Rockies/Great Basin/etc. - for any extended periods during the past few summers (or in the more distant past)? Ted (and others), what other species would you consider typical in the early July flights? And what of mid-June to early July flights in Colorado and elsewhere in the west? And expanding to a larger scale, what do we know about nocturnal movements associated with molt migration in other parts of the world (especially outside the western hemisphere!)? >From the US, East coast perspective, I am also interested to hear opinions about the nature of nocturnal movements that occur between mid-June and late-July in the Northeastern US. Presumably, in some cases, we are recording actual, continuous migratory movements for species that are late/early migrants (rails/Yellow Warbler, Louisiana Waterthrush) . . . but is this true in all cases? Are there species, such as those in the next sentences, for which we think we have a clear understanding of migration phenology but for which we really do not? Could be . . . but consider this . . . A number of mid-June to mid-July recordings made in New York state (various people in Ithaca and Manhattan at the least) have turned up an interesting diversity of nocturnal flight calls including Sora, Virginia Rail, Black-billed and Yellow-billed Cuckoo, Black-throated Blue Warbler, Canada Warbler, Grasshopper Sparrow, Nelson's Sparrow, etc. The placement of the recording stations and the attributes of the recordings are consistent with recording birds in nocturnal flight (rather than flight calls recorded nocturnally from birds on the ground or in typical habitat). Are we recording movements of adults of multi-brooded birds, failed breeders, pre-migratory movements of young of the year, facultative movements following irregular resources? Best, Andrew On Wed, Jul 28, 2010 at 5:00 AM, Ted Floyd wrote: > Hello, Birders. > > Here's an 86-kilobyte PowerPoint image, attached, summarizing the > results of my nighttime listening efforts at Greenlee Preserve, Boulder > County, Colorado, 2007-2010. Boulder County is northwest of Denver. The > county's western boundary is the Continental Divide, and the eastern > boundary is a bit higher than 5,000 feet. Data are July-November, > 2007-2009, plus July to date in 2010. > > Before opening up the file, I suggest thinking for a
RE: [nfc-l] flight call to identify
Upon listening to it again, I could go with LeConte's as well, though it seems to have a fairly short delivery for a LeConte's to my ear. I also didn't really hear the double-banding initially. Maybe Ted's other suggestion should be explored. Jay -Original Message- >From: Ted Floyd >Sent: Jul 30, 2010 8:22 AM >To: NFC-L@cornell.edu >Subject: RE: [nfc-l] flight call to identify > >Hi, all. > >Assuming it's a "flight call" (I'm thinking functional), it sounds and >"looks" (spectrographically) good for Le Conte's Sparrow. The flight >call is thin, slightly descending, very high pitched, and double banded. >That's all a good match to Le Conte's Sparrow's flight call. > >But just to ask a stupid question, why isn't this an alarm call of an >American Robin? That's an awfully variable vocalization, I realize, but >I've heard some that are just like this one. > >Is there's a chance the microphone picked up a robin in a tree, freaked >out by a raccoon or something? Or is this definitely a bird flying over? > >Anyhow, my vote, for what that's worth, is Le Conte's Sparrow. But I >wonder about a non-FlightCall vocalization of American Robin, too. > >Best, >Ted > > > > > > >-Original Message- >From: bounce-6141374-9667...@list.cornell.edu >[mailto:bounce-6141374-9667...@list.cornell.edu] On Behalf Of Andrew >Farnsworth >Sent: Thursday, July 29, 2010 3:53 PM >To: NFC-L@cornell.edu >Subject: [nfc-l] flight call to identify > >Good afternoon all, >I'd like to solicit comments from the community on this flight call, >recorded on approximately 5AM on 17 October 2009 just south of Ithaca, >NY, USA. What is the identity of the caller? Several colleagues and I >have a likely candidate, but I'd like to hear additional opinions. > >Once I get some feedback, I'll post the comments and discussion, and >provide some additional background. > >Regards, >Andrew > >-- > >NFC-L List Info: >http://www.NortheastBirding.com/NFC_WELCOME >http://www.NortheastBirding.com/NFC_RULES > >ARCHIVES: >1) http://www.mail-archive.com/nfc-l@cornell.edu/maillist.html >2) http://birdingonthe.net/mailinglists/NFCL.html >3) http://www.surfbirds.com/birdingmail/Group/NFC-L > >Please submit your observations to eBird: >http://ebird.org/content/ebird/ > >-- > >-- > >NFC-L List Info: >http://www.NortheastBirding.com/NFC_WELCOME >http://www.NortheastBirding.com/NFC_RULES > >ARCHIVES: >1) http://www.mail-archive.com/nfc-l@cornell.edu/maillist.html >2) http://birdingonthe.net/mailinglists/NFCL.html >3) http://www.surfbirds.com/birdingmail/Group/NFC-L > >Please submit your observations to eBird: >http://ebird.org/content/ebird/ > >-- > -- NFC-L List Info: http://www.NortheastBirding.com/NFC_WELCOME http://www.NortheastBirding.com/NFC_RULES ARCHIVES: 1) http://www.mail-archive.com/nfc-l@cornell.edu/maillist.html 2) http://birdingonthe.net/mailinglists/NFCL.html 3) http://www.surfbirds.com/birdingmail/Group/NFC-L Please submit your observations to eBird: http://ebird.org/content/ebird/ --
RE: [nfc-l] flight call to identify
Hi, all. Assuming it's a "flight call" (I'm thinking functional), it sounds and "looks" (spectrographically) good for Le Conte's Sparrow. The flight call is thin, slightly descending, very high pitched, and double banded. That's all a good match to Le Conte's Sparrow's flight call. But just to ask a stupid question, why isn't this an alarm call of an American Robin? That's an awfully variable vocalization, I realize, but I've heard some that are just like this one. Is there's a chance the microphone picked up a robin in a tree, freaked out by a raccoon or something? Or is this definitely a bird flying over? Anyhow, my vote, for what that's worth, is Le Conte's Sparrow. But I wonder about a non-FlightCall vocalization of American Robin, too. Best, Ted -Original Message- From: bounce-6141374-9667...@list.cornell.edu [mailto:bounce-6141374-9667...@list.cornell.edu] On Behalf Of Andrew Farnsworth Sent: Thursday, July 29, 2010 3:53 PM To: NFC-L@cornell.edu Subject: [nfc-l] flight call to identify Good afternoon all, I'd like to solicit comments from the community on this flight call, recorded on approximately 5AM on 17 October 2009 just south of Ithaca, NY, USA. What is the identity of the caller? Several colleagues and I have a likely candidate, but I'd like to hear additional opinions. Once I get some feedback, I'll post the comments and discussion, and provide some additional background. Regards, Andrew -- NFC-L List Info: http://www.NortheastBirding.com/NFC_WELCOME http://www.NortheastBirding.com/NFC_RULES ARCHIVES: 1) http://www.mail-archive.com/nfc-l@cornell.edu/maillist.html 2) http://birdingonthe.net/mailinglists/NFCL.html 3) http://www.surfbirds.com/birdingmail/Group/NFC-L Please submit your observations to eBird: http://ebird.org/content/ebird/ -- -- NFC-L List Info: http://www.NortheastBirding.com/NFC_WELCOME http://www.NortheastBirding.com/NFC_RULES ARCHIVES: 1) http://www.mail-archive.com/nfc-l@cornell.edu/maillist.html 2) http://birdingonthe.net/mailinglists/NFCL.html 3) http://www.surfbirds.com/birdingmail/Group/NFC-L Please submit your observations to eBird: http://ebird.org/content/ebird/ --
