Subject: [Tweeters] chestnut-backed chickadee incubation
Date: May 29 08:22:55 2008
From: Robin W Baird - RWBaird at cascadiaresearch.org


Hello all,

Thanks to folks who provided information on time to fledging in chestnut-backed chickadees. Unfortunately the eggs in our video monitored nest have not hatched (normal incubation is reportedly 11-18 days, today is day 23 since all 6 eggs were laid and incubation started full time). I'm now wondering how long a female might continue to incubate eggs that aren't going to hatch? The female does not leave the box for more than ~5-7 minutes at a time, regularly turns the eggs, and the male is continuing to feed her on a regular basis in the box (a short video clip at http://www.flickr.com/photos/89985360 at N00/). In theory they could still hatch but the chances must be very low, and I'm surprised that the female (or the male) haven't abandoned them yet. Also, would appreciate hearing from anyone who has watched eggs closely in the days prior to hatching. About five days ago the eggs developed clear air bubbles at the wide end and a couple appear to be getting some small freckling, but not sure if there are any implications for the chances of the eggs hatching?

in other bird news, we had a fledgling rufous hummingbird yesterday, and our first fledgling house finch on the 26th (off South Bay Road, Olympia).

thanks,

Robin Baird
rwbaird (at) cascadiaresearch.org
Olympia, WA