Hi Andy, Here in Europe there is at least one species of grebe that vocalises in flight at night-time, although so far I've only recorded it three times between March and July. I am referring to Little Grebe Tachybaptus ruficollis, which has a whimbrel-like flight call, preceded by a few much higher-pitched notes. On at least one of these occasions, the birds was probably migrating.
Based on this I'd say there's a good chance that other grebes may also have nocturnal flight calls. regards, Magnus Robb -- 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/ --
