Cranky Bees. They are one of the worst nightmares of a beekeeper. Cranky bees are not enjoyable to keep. They have aggressive tendencies and are overprotective of the hive. Often when you have cranky bees, you will be unable to get near the hive or you will get stung. Sometimes these bees chase you for just being within eyesight of the hive. In my case, I could not tend to my garden without honeybees hitting my head and face. After investigating why this nice hive turned mean, it was clear that I needed to re-queen this hive. But where do you begin when this happens in your own backyard apiary? Here are some things to consider.
Bad Weather. One thing new beekeepers quickly learn is that honeybees prefer calm days with abundant sunshine. They do not care for cloudy, windy, or rainy weather. These types of conditions as well as other weather extremes greatly affect the bees’ temperament. Thus, it is never recommended to go into a hive on less-than-optimal days.
Hive Inspection/Manipulation. Any of us would be upset if someone came into our homes and began poking and prodding around. It is only natural that the bees become aware and protective of their home. Sometimes, bees can be cranky for a few days following a more thorough inspection or hive manipulation. So, when going into the hive consider the time of day. The optimal time to enter the hive is later morning until early afternoon during times of good weather. Using a smoker during the inspections can also cut down on hive crankiness afterward.
Starvation. Hungry and thirsty bees are not happy nor should they be. Pay attention to the nectar and pollen availability in your area and remember to feed the bees during droughts and nectar dearths to prevent crankiness and other bee issues.
Predators. Bee predators that lurk around the hive can cause bees to increase the defensiveness of the hive. Sometimes it takes a bit of detective work to see if this is a cause of bee irritability. Skunks for example love to bring their families to the hives at night during the summer when the bees cool their hives by bearding. Skunks are only sensitive to bee stings on their abdomens. Therefore they sit outside the hive and pick off bees one by one until they have had their fill.

Mean Queen. All the other bees in the hive emulate the personality and temperament of the queen. If the queen is nice, the hive should be gentle. If she is nasty the hive will turn nasty. In this situation, beekeepers are encouraged to re-queen the hive.
Queenless. If the queen goes missing through death or another mishap, the hive soon senses that she is gone. As they work to re-queen the hive, they can become more protective and defensive until the new queen emerges, mates, and sets the overall tone of the hive.
Aggressive Cross-breeding. East African lowland honey bees are pretty aggressive and sometimes known colloquially as “killer bees.” Cross-breeds between East African and European or North American bees are referred to as the “Africanization” of bees. Virgin queens will mate with available drones in the area. Even if you are in an area where Africanized bees do not reside, it is not entirely impossible that some Africanized traits/genes traveled in packaged bees to your area. These drones then mate with the local virgin queens and then incorporate their genetics into the local gene pool. If you suspect this has happened, the first step is to re-queen the hive with a mated queen and see if it makes a difference.