Thanks specialkayme and Larry Bees, now I don't feel quite as stooopid.
I'm sure I still look stooopid, running around trying to catch swarms I do happen to see leave the hive (I have at home). My other hives are in out yards. And I know the bees are secretly plotting behind my back, to make sure they annoyingly decide to leave when I'm not around. They also totally ignore the bait hives I set out.....
Also, this is a very (very!) rainy cool northern island. I didn't expect them to swarm while it was still rainy/overcast, etc. Plus, none of the hives were even close to being crowded or honey bound.
It's just hard to lose half your bees and honey.....
Next time, they're all going to be grounded until their 18th birthday. And no TV!