Bron - A good example on my part of extrapolating, chatline-fashion, from inadequate data. However, I think there is a valid generalisation in there somewhere. My theory now (still from less than adequate data) is that White-browed fledglings will engage in the behaviour in a higher proportion of anti-predator situations than Dusky fledglings. The behaviour is the rigid posture with upraised bill. Most recent fledglings will freeze as an anti-predator response. g
From: Bron King [
Sent: Friday, 10 January 2014 10:31 PM
To: Geoffrey Dabb;
Subject: Re: FW: [canberrabirds] White-browed Woodswallows - dy defensive pose
I apologise. When I checked after I read your observation Geoffrey, I realised that the photo to which I linked
was of Dusky Woodswallows, seen at L. Ginninderra.
(We'd been watching White-broweds at Boorowa a day or two earlier and I mislabeled the photo).
Bron
Yes - I have seen that freezing behaviour, head raised stiffly, sufficiently often with White-broweds to think it is typical early fledging (not necessarily premature fledging) behaviour in response to a possible predator. It does not seem to happen with Duskies, for example the below premature fledger (discussed earlier) at Stony Creek which remained active and was eventually called back to the nest site by the parents. One assumes that the alarm calls by the parents prompt freezing (up to a point) in the White-browed, otherwise with Duskies
******************************************************************************************************* This is the email announcement and discussion list of the Canberra Ornithologists Group. Please ensure that emails posted to the list are less than 100 kB in size. When subscribing or unsubscribing, please insert the word 'Subscribe' or 'Unsubscribe', as applicable, in the email's subject line. List-Post: List-Help: List-Unsubscribe: List-Subscribe: List archive: List manager: David McDonald, email
