Thanks for your question, the picture was very helpful as I was trying to determine whether we were talking about bumble bees, or Carpenter bees.

Carpenter bees look quite similar to bumble bees, so it's easy to misidentify them. Look at the upper side of the bee's abdomen to differentiate the two kinds of bees. While bumblebee abdomens are hairy, the top of a carpenter bee's abdomen will be hairless, black, and shiny.

From the picture I cannot see whether the abdomen is smooth and shiny or hairy. If hairy, then the insect is question will be bumble bees. In gardens, bumblebees tend to nest in relatively undisturbed areas such as shaded corners. Some will also nest under structures such as sheds. They do not like to nest in areas with prolonged exposure to the sun as this can heat the nest too much.

Bumblebee nests vary in size depending on the species and time of year. A well-established nest may contain up to 400 bees. Honeybee hives typically contain 50,000 bees so bumblebee nests are very small in comparison.

Please note that though bumblebees are not generally aggressive, they might get aggravated if you interfere with the nest itself. They don't form swarms, but you may see a cloud of male bees flying outside the nest, as in the video below. They should just get on with life and do their own thing - doing a wonderful job of pollinating plants, wildflowers and your vegetables. Even the very largest nests produce very little "traffic" in and out, so you won't see threatening numbers of bees at any point during the summer.



If the bees are living under your shed, and are coming up through holes in the floor, then this is probably because it's the easiest way in and out for them. If you make a different hole, from the outside of the shed, and then block up the hole they were using, then they should happily take to their new route.

Bumblebee nests don't live for long, so the nest should die naturally within a few months. After that time, the new queens will have flown from the nest to hibernate in the soil elsewhere.

It is possible (although not particularly likely) that a different bumblebee queen will find and use the same hole next year. The old nest will die in the autumn though, and all the bees will have left or died. If you don't want bees in the same place again you can block the entrance to the nest up after it dies down. But please, don't kill them. Honey bees and bumble bees are in decline, so they need our help.

I hope this helps,

Thank you so much for your quick response, and all the info! It was very helpful!

Are the new really big bees coming from the nest the new queens getting ready to leave and hibernate?

I think so. Keep in mind the complete life cycle:

Queens hatched at the end of the previous year’s colony cycle that mated in the early fall of that year are the only bumblebee individuals that survive the winter. They hibernate in the soil typically in a location that will not warm up too quickly or too early in the spring (to avoid a potentially lethal early emergence). Once these queens do emerge they begin to look for a suitable nest location and then begin to vigorously gather both nectar and pollen.

So, the first bumble bees that you see in the spring will be queens. Workers (and later in the year drones) are not produced until a nest is established, 4-5 weeks after a queen emerges from hibernation. The queens of the different bumble bee species in your area will emerge at different times over a 4-6 week period. In Nebraska, we tend to see our first species of bumble bee queens the second week of April, with queens of different species emerging from hibernation through May.

As the nest becomes larger and its workers become more efficient in accumulating pollen, the queen lays more and more eggs. Toward the end of summer, though, the queen begins to lay and brood these eggs differently. By withholding a pheromone from fertilized eggs and by increasing the amount of the food supply given to the developing larvae, female bumblebees begin to develop into new queens. And, by laying unfertilized eggs, which then begin to develop into larvae and adults, the queen begins the formation of male bees. These new queens and males are signs that the colony has begun its inevitable, seasonal decline.