Thanks for all the replies!
Definitely difficult to tell... I've been reading (elsewhere) of those with experience on YJs systematically destroying their hives and I think they are, at least, a contributing factor.
Cindi ~> yes, I've been trapping them and even found one nest (which I immediately destroyed) but it was further away and they still keep coming. I'm actually not seeing so
many of them now. But when I open a hive and a YJ comes out, it's not encouraging (happened one time).
and on another section of that site it tells the symptoms, does yours match?
and this was in your first post
One hive is dead 100%. Loads of honey, "bee-bread" but no live bees whatsoever. Dead larvae, dead emerging (newborn) bees and a small blanket of dead ones on the bottom (SBB).
see the first line in the top quote with little or no dead bee's,,,,, could have been the first one to get it and died out, the second hive you could have caught in time to see it, you never said how many dead was in the second hive? it could be yellow jacket but does sound like symptoms of CCD from what you are saying....
oH SORRY HAD MY TINFOIL HAT ON AGAIN
I hi-lighted in red the part of my first post which makes me think it is not CCD. "Small blanket" meaning the bottom was blanketed in dead bees, and by "small" I meant not a deep pile... but definitely significant numbers (~100+?).
I appreciate everyone's input. Leaving the postmortem & diagnosis speculation aside for now (please) could anyone please help me with this previous question ~> is freezing the only safe method of storing filled frames? I've already treated the empty hive with Bt (for wax moth) and have it closed 100%, but still in the bee yard.
btw - I took a couple of frames (w/larvae & live bees) and did a swap from a strong to the lonely-queen hive yesterday. Unsure if it was too late or not.