[Bluebird-babble] fledglings & counting nestlings

[Christina.Mitchell at UCHSC.edu]

I sent this earlier, but (given a weird response I got) I think it didn't go through.  My apologies if it's a repeat.
 
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Hi, all--
 
I have a couple of questions for the more experienced monitors among us. 
 
We have a number of boxes with nestlings in them.  I got pretty confident at counting the eggs with my telescoping mirror, even when the parents were making their presence known to me.  But with nestlings, I'm having a harder time getting an accurate count.  Part of it is that it's just harder to see those little heads; part of it is that I'm especially aware of the parents' presence and I try to spend as little time at the open box as possible; part of it is that I'm a volunteer at a wildlife rehab sanctuary and I hate setting off that gaping instinct in the nestlings when I don't have any food to offer them.  The form says to put an X if we can't determine the number of either eggs or hatchlings.  However, I can usually get a "well, there's at least 3 beaks there" count.  But that's not really science, now is it?  What do others advise?
 
Also, last weekend (5/18), I counted (about) 4 Juniper Titmouse nestlings, very tiny but eyes open, looking quite healthy and gaping very nicely.  (The previous week (5/11), no hatchlings--just eggs.)  This weekend (5/25), the nest was completely empty.  Birds of North America estimates 16-21 days as nestlings; if all of the eggs had hatched immediately after I left 2 weeks ago, and they fledged the second before I got there this weekend, they would have been about 13 or 14 days old--which seems a tad young.  But since the nest appeared completely intact and undisturbed, should I just assume that they got lots of good nutrition and care and are in the extremely early part of the statistical distribution?  I think the form just asks for the # of eggs/nestlings found on a particular date and doesn't ask me to determine anything about fledglings per se--so maybe I just don't need to worry about this.  
 
Thanks for any advice people have.
 
Tina Mitchell
pinyon-juniper habitat, 7100', 18 miles east of Salida
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