Well, I've been grafting daughter queens from three mother queens that I imported into my operation in the Spring of 2009. One of the three was my favorite to graft from, I really like(d) her daughters. Anyway, all three mother queens were living in their own double 5-frame medium depth nucs (all-together ten frames for each queen and her entourage), all of them were fed pollen substitute and sugar syrup whenever food was unavailable naturally. They all maintained large brood nests and strong populations through the Summer of 2009. I needed to regularly harvest sealed brood and combs of sealed honey to ensure a continuous supply of grafting age larva and that they didn't get strong enough to swarm.
Well, every time I opened these mother queen nucs, I was always extremely careful to make mental note of where the queen was, so that when I moved frames I would not be putting her in harms way. I call(ed) them MQa, MQb, and MQc; quess what the acronym's mean. Anyway, MQb went missing about three weeks ago, now MQa has gone missing about two days ago. At least MQc is still with us, at least the last time I opened her hive to harvest larva.