Dan, Debbie, and All, Thanks for the reference Dan. It is indeed an exciting paper that breaks new ground and raises intriguing questions. In reference to the paper’s conclusion about the need for larger-scale studies, I would add that there is a corresponding need for smaller-scale studies of aerial habitat, using smaller marine-type radar and acoustic monitoring.
In response to Debbie’s question, one of my sites is about 20 km inland and in a ravine with a river at the bottom and thus at very low elevation relative to the surrounding topography. Yet this site has relatively high counts of flight calls (in a dark forest environment) in the autumn. I hypothesize that this is due to migrants following the river system to the coast. At another site located on a coastal headland, I also have high counts in the autumn. Two stations that are 1.5 and 3.0 km from the headland have increasingly smaller counts with distance from the headland. Here I hypothesize the higher counts (and probably lower altitudes) at the headland are due to re-orientation behaviour. John Carleton, NS From: dmenn...@gmail.com [mailto:dmenn...@gmail.com] On Behalf Of Daniel Joshua Mennill Sent: December-05-16 12:37 To: Debbie Leick <dle...@mpgranch.com>; nfc-l@cornell.edu Cc: John Kearney <john.kear...@ns.sympatico.ca>; Kate Stone <kst...@mpgranch.com>; Carrie Voss <cv...@mpgranch.com> Subject: Re: [nfc-l] 2016 Fall NFC Update All, In relation to this question, there is an exciting new paper in the journal Biology Letters about the height of nocturnal migrants: "Where in the air? Aerial habitat use of nocturnally migrating birds" by Kyle Horton and colleagues. The article reports a lot of variation in flight height of nocturnal migrants. In relation to inland versus coastal habitat, the authors report: "migrants tended to fly slightly higher at inland sites compared with coastal sites during spring, but not during autumn." Here is the full abstract. The lower atmosphere (i.e. aerosphere) is critical habitat for migrant birds. This habitat is vast and little is known about the spatio-temporal patterns of distribution and abundance of migrants in it. Increased human encroachment into the aerosphere makes understanding where and when migratory birds use this airspace a key to reducing human–wildlife conflicts. We use weather surveillance radar to describe large-scale height distributions of nocturnally migrating birds and interpret these distributions as aggregate habitat selection behaviours of individual birds. As such, we detail wind cues that influence selection of flight heights. Using six radars in the eastern USA during the spring (2013–2015) and autumn (2013 and 2014), we found migrants tended to adjust their heights according to favourable wind profit. We found that migrants’ flight altitudes correlated most closely with the altitude of maximum wind profit; however, absolute differences in flight heights and height of maximum wind profit were large. Migrants tended to fly slightly higher at inland sites compared with coastal sites during spring, but not during autumn. Migration activity was greater at coastal sites during autumn, but not during spring. This characterization of bird migration represents a critical advance in our understanding of migrant distributions in flight and a new window into habitat selection behaviours. Dan Dan Mennill Associate Professor Chair, Biology Graduate Program Department of Biological Sciences University of Windsor Email: dmenn...@uwindsor.ca <mailto:dmenn...@uwindsor.ca> Web: www.uwindsor.ca/dmennill <http://www.uwindsor.ca/dmennill> On Mon, Dec 5, 2016 at 11:27 AM, Debbie Leick <dle...@mpgranch.com <mailto:dle...@mpgranch.com> > wrote: Yes, makes me wonder, too. Do you have any sense of this from the monitoring you've done? ---------------- From: John Kearney Sent: 12/2/2016 1:21 PM To: 'Debbie Leick'; nfc-l@cornell.edu <mailto:nfc-l@cornell.edu> Cc: 'Kate Stone'; 'Carrie Voss' Subject: RE: [nfc-l] 2016 Fall NFC Update Hi Debbie, Very interesting work. Low elevation in your area would be very high in a coastal area. It makes me wonder how the preferred flight altitude of a migrant is related to sea-level and local geography. John Carleton, NS From: bounce-121048772-28417...@list.cornell.edu <mailto:bounce-121048772-28417...@list.cornell.edu> [mailto:bounce-121048772-28417...@list.cornell.edu <mailto:bounce-121048772-28417...@list.cornell.edu> ] On Behalf Of Debbie Leick Sent: December-01-16 22:44 To: nfc-l@cornell.edu <mailto:nfc-l@cornell.edu> Cc: Kate Stone <kst...@mpgranch.com <mailto:kst...@mpgranch.com> >; Carrie Voss <cv...@mpgranch.com <mailto:cv...@mpgranch.com> > Subject: [nfc-l] 2016 Fall NFC Update Hi NFCers, We posted a short update with preliminary results from our fall NFC monitoring. If you are interested in learning more about what we found in western Montana, please follow the link below: http://www.mpgranch.com/research/latest-research/fall-migration-2016-acoustic-monitoring-update.aspx Regards, Debbie Leick MPG Ranch Florence, MT -- 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 eBird <http://ebird.org/content/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/ -- -- 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/ -- -- 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/ --