Tom (Expectant Father) Foote wrote:

>This little bird began her *sit* about July 6 or 7...she's been on the
>nest ever since... my *Birder's Handbook* says 14-15 days Incubation..
>Today I finally couldn't stand it any longer and noticing she was off
>somewhere, I got the short ladder and peeked in the nest...4, count 'em,
>4 little eggs..Now, that must mean she sat in the nest for a long time
>before she laid..however, some of you remember my sad little post earlier
>where I said she had abandoned the nest and there was one egg in it..
>well, that must mean at least one of these eggs (assuming it's still in
>that clutch) is almost a month old...sighh-hhh...
>
>So, Dennis...is this *normal* behavior for the Pacific Slope Flycatcher?
>Would she sit there with no eggs under her for a long time before she
>laid? Is she sitting on addled eggs? How long before she figures out the
>eggs aren't going to hatch? (assuming they won't)..will she leave them in
>the nest?

Yep, it is normal behavior for a bird to incubate its eggs until they hatch
(that being what they normally do). If they are infertile or for other
reasons don't develop normally they will prolong the incubation period for
days to, I suppose, a few weeks. At some point they will give up. They've
got to get on with their life. A passerine bird wouldn't sit on the nest
before the ultimate or penultimate egg is laid, so you're right that on
7/30 she's been on the nest too long.

You can tell *us* how long it will be before she "figures out" the eggs
aren't going to hatch. I imagine she will just disappear, leaving you a
nest of eggs.

Dennis Paulson, Director phone: (206) 756-3798
Slater Museum of Natural History fax: (206) 756-3352
University of Puget Sound e-mail: dpaulson at ups.edu
Tacoma, WA 98416