The forepart of the abdomen is yellow and there is some yellow between the four brown bands on the rest of the abdomen. The Caucasian variety, a mild-tempered bee, is dark, and its abdomen is banded with grey.

An established honey bee colony will sometimes divide itself, and one or more swarms will leave the hive. The new swarm may cluster for a while on a tree limb or bush near the old hive while scout bees search for a suitable place to establish a new home. Usually scout bees find a hollow tree, but occasionally they will choose the wall voids of a home. Unfortunately, bees may nest in the wall or attic some distance from where they enter the wall.

Are they about 2cm long? If much bigger or smaller, they are not honey bees. Very large bees are usually carpenter bees. Very small bees may be any of many species of mostly non-social bees.

Are they yellow jacket wasps? Yellow jackets are about the same size as honey bees, and nest in moderate-sized colonies. They are dark black and bright yellow, with clearly defined black and yellow bands. Honey bees are more brownish, and fuzzier, with less well-defined bands

Are They Foraging Bees, A Swarm in Transit, Or an Established Colony?

If you just see many bees flying around flowering plants, they are most likely just foragers visiting the flowers for nectar and/or pollen. Foragers can sting, but generally only do so if they are trapped or crushed. There is little than can be done to deter foraging bees except to remove the flowers.

If you see a cluster of bees hanging in a tree, ranging in size from a baseball to bigger than a football, it is probably a swarm. Swarming bees are bees that have left their original colony, with the old queen, and are looking for a suitable cavity in which to form a new permanent nest. When they find one, they will move on again en masse, usually in a few hours to a few days after they land. The tens of thousands of flying bees in a swarm taking off or flying is a very dramatic sight, but usually not a great danger. Since the bees have little to defend, swarm bees are usually docile (but not always, so don’t disturb them). If you can see the edges of wax honeycombs sticking out of the cluster, or if it remains in place for a week or more, it is probably an established colony.

If you see many bees coming and going from the same place (usually a hole that leads to their nest cavity, but sometimes you will just see them flying out of vegetation at one place), they are probably an established colony, living in nest made of beeswax combs that they build, usually, but not always, inside a cavity. These are the most troublesome, because they are permanent, and because the bees are more likely to defend their nest by stinging. I generally advise people to remove established colonies as soon as they can after they discover them, because the colony will continue to grow, build more comb, store more honey, and become more defensive. Unfortunately, it is not terribly simple to remove an established colony inside a cavity.

Dealing with Bees in The Wall

Removing a bee colony from a wall is probably not something you want to do yourself. I recommend calling a professional. You want to get someone who has the equipment and experience to deal with bees, and do it right. Not all pest control operators will do all that I recommend here, and I think you are asking for trouble if you just have the bees killed and nothing else, so persist in finding someone to do the complete job.