This is the time of year when a beekeeper discovers a hive with no eggs and the brood is only found in advanced stage (capped brood). No eggs or young larvae.
The hive is queenless, right?
Many times this is not the case. What usually happens, the hive has swarmed and a new queen may be in the hopper but not laying yet.
So here is the rub, if you just run out and purchase a queen and there is a virgin queen in the hive. The virgin queen will kill that queen you just plopped down some serious money on. Don't buy a queen and let them "fight it out", this does not work. In the mean time the nectar flow is on and the bees are filling the brood nest with nectar.
Most newer beekeepers are in denial that their bees swarmed. One look at the door of the hive can tell you that the activity at the front door of the hive has diminished.
So, how do you know what to do?
This is where having at least two hives can give you a plan B. Take a frame of eggs from the queenrite colony. Place that frame in the top of the top brood box of the possible queenless hive, so it is easy to look at. This frame will do two things.
1. The presence of brood in the colony can prevent the colony from turning into laying workers if it truly is queenless.
2. Check this frame after about five days. If the bees are building queen cells, one can surmise the hive needs a queen. If the hive does not try to make queen cells, one would surmise that there is a queen in the hive and she should start laying in a couple of weeks.
This time of year don't jump the gun on queen replacement. Patience wins the day.