Hi all, I've recorded Great Bittern night flight calls from time to time in the Netherlands, Portugal and elsewhere and they were always single notes. One of the most striking thing about them is the very long gap between calls, typically 30 seconds to a minute during night flights. When recording them I wait at least 90 seconds after the last call before hitting the stop button! The times I've heard more frequent calls have been when birds were leaving marshes at the start of a migration leg, when presumably the chances of attracting a conspecific to come with them were greatest. In one beautiful recording by Arnoud van den Berg made at Lauwersmeer in the Netherlands, you can heard fairly short gaps and double notes, but they are clearly from two different birds answering each other. He saw them both as they took off, flew overhead about 20m apart, then disappeared.
all the best, Magnus On 6 Oct 2011, at 20:36:48, Andrew Farnsworth wrote: > Hi all, > Well, at least Minnesota and Alabama are both in the US . . . my > apologies for the incorrect location reference! The discussion of > bittern flight calls has piqued my curiosity about Great Bittern - > Magnus and others, what generalization, if any, have you about single > versus double call notes in nocturnal migration from that species? > > Best, > Andrew > > On Thu, Oct 6, 2011 at 15:14, Bill Evans <[email protected]> wrote: >> The original recording was from south-central Alabama in the early morning >> (~4AM) of October 8, 1989. Andy cut out the dead space between calls. The >> actual sequence is over a minute long and one can interpret the bird >> approaching and then flying away. This is the only time I've heard a double >> croak from American Bittern -- all other occasions have been single croak >> events. I think on most of my night flight call recordings there is usually >> only a single call detected from a passing individual. Uncommon but regular >> flight call here in central NY. >> >> Bill E >> >> >> ----- Original Message ----- From: "Andrew Farnsworth" >> <[email protected]> >> To: <[email protected]> >> Cc: <[email protected]>; "Bill Evans" <[email protected]> >> Sent: Thursday, October 06, 2011 1:38 PM >> Subject: Re: [nfc-l] American Bittern NFC >> >> >> Hi all, >> I've certainly heard American Bittern produce isolated notes more >> often than not when I've heard them migrating at night, both in the >> field and in the lab from recordings; I'd hazard a guess to say that >> the single note call is more likely to be encountered . . . but this >> is really pure speculation, when it comes down to it, because I've not >> heard a tremendous number of bitterns in flight at night! >> >> Best, >> Andrew >> >> On Thu, Oct 6, 2011 at 12:11, Chris Tessaglia-Hymes <[email protected]> >> wrote: >>> >>> Andrew, >>> >>> Thanks for pulling this together, and thanks Bill, for providing these >>> clips! >>> >>> Is it most typical for American Bitterns to produce these paired calls >>> during migration, or do they often just do single isolated notes? >>> >>> This is very helpful! >>> >>> Thanks again! >>> >>> Sincerely, >>> Chris T-H >>> >>> -- >>> Christopher T. Tessaglia-Hymes >>> TARU Product Line Manager and Field Applications Engineer >>> Bioacoustics Research Program, Cornell Lab of Ornithology >>> 159 Sapsucker Woods Road, Ithaca, New York 14850 >>> W: 607-254-2418 M: 607-351-5740 F: 607-254-1132 >>> http://www.birds.cornell.edu/brp >>> >>> >>> >>> -----Original Message----- >>> From: Andrew Farnsworth [mailto:[email protected]] >>> Sent: Thursday, October 06, 2011 11:59 AM >>> To: Chris Tessaglia-Hymes >>> Cc: [email protected]; Bill Evans >>> Subject: Re: [nfc-l] American Bittern NFC >>> >>> Hi all, >>> With Bill Evans's permission, I attach a heavily edited cut of American >>> Bittern flight calls that Bill recorded and sent to me - I believe these >>> recordings come from Minnesota, though I cannot say for sure without some >>> further investigation. This is certainly the best recording I have, I am not >>> sure and have not yet checked if others exist in Macaulay or Xeno-Canto. >>> >>> Best, >>> Andrew >>> >>> On Thu, Oct 6, 2011 at 09:59, Chris Tessaglia-Hymes <[email protected]> >>> wrote: >>>> >>>> Does anyone have an example of an American Bittern NFC they could >>>> attach and post to the List? >>>> >>>> >>>> >>>> Thanks! >>>> >>>> Sincerely, >>>> Chris T-H >>> >>> >> >> >> >> >> -- >> >> 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/[email protected]/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/[email protected]/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/[email protected]/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/ --
