Last fall I got 8 bee boards from an abandoned alfalfa farm. The first time I looked at them they were active. In fact, driving up I thought they were honey bees, there were so many. Late in the fall, when there was no longer any flight I transported them to our place. Almost all the holes were sealed cocoons.

Now it is mid June and I have seen none emerge? Alfalfa is just starting to bloom. Did they die? We had a mild winter. What is going on?