I also had an opposum problem. My hives are on my deck and
on stands up off the deck floor. The two suggestions I have tried
are:
 
        1. Put chicken wire on the ground around the hives.
Apparently the offending animal doesn't like the feel of the wire
around their leg when the walk on it. (I tried this on my deck but
I had additional visits. I may be because of the flatness of the
deck surface.)
 
        2. Put baited mouse traps out and snap their noses or
paws. I wired the traps (six total around the 3 hives) to the
chicken wire on the deck floor and baited with a dab of
peanutbutter and a tiny slice of apple. The first night an opposum
set off one of the traps. I heard the trap go and flipped on the
light to see the opposum skulking away.
 
        At this point the apple and peanutbutter are long gone but
I leave the traps set. The rain has set off a few so I reset them.
I seems to be working for the moment. My cranky hive is very much
less cranky, though still the hive with the most personality and I
haven't seen any evidence of visits.
 
        Hope this helps.
 
 
        Jim Moore
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