>>>I have two hives, both feral colonies obtained this April.  One hive is
doing very well; the other hive is a non-performer. The poor hive is
working on only two full frames and will not expand.

I have had that a few times. If they can't seem to pick up by themselves,
or if there is a smaller than normal hive coming through the winter, I add
frames of sealed brood from strong hives. If there are fresh eggs in there
the better because I have also noticed with the occasional hive that
wouldn't pick up that they like to requeen several times, so with added
fresh eggs they might raise themselves a queen that is more productive.
Just adding bees from a stronger hive doesn't seem to help mine as much as
adding sealed brood. Usually by summer time such a hive will be going all
right.

>>>Introducing a commercial queen is not a possibility - we cannot get them
here.

During the next weeks I will work my hives and move them back into the
beehouse for the winter. If I find one hive that is too weak and not able
to pick up in my opinion I will have no choice but to combine it with
another hive. While there may be enough time for them to raise another
queen it might be way too late in our northern season for her to raise
enough new brood to get her through the winter. It's probably possible for
us to somehow buy/import queens from elsewhere however, for a number of
reasons, we are trying hard to remain selfsufficient in that regard. We are
only some small homeowners keeping bees but we try.

>>>The bees all seem healthy - they are active foragers.  There are no
distressed bees near the entrance or on the ground, no Foul Brood, no mites
- they are not known to be in Bequia although I'm sure they are coming.

Kinda similar here (our location: Northern British Columbia, just about
underneath the Alaskan border). Our northern area was considered being
under quarantaine for the past year or two because we were still mite free.
Now it's too late except for some isolated pockets like possibly our
valley. Husband is very afraid to purchase bees or queens from elsewhere to
add to ours. So far ours had remained healthy and we never had to deal yet
with any sickness or infestations.

>>>Bob in Bequia.

Bequia is where, if I may ask?

                Ma. / Nass Valley - British Columbia CANADA