by Sandy Garland
The other day, Berit sent me a photo of a bumble bee carrying another one. She wondered about this behaviour: why? how?
Large “bumble bee” carrying a smaller one. Photo by Berit Erickson.
I posted her cell phone photo on Facebook, in the Insects and Arachnids of Ontario group, and was astonished at the response. This was not a bumble bee at all! It was immediately identified (by Brian Robin – thanks!!) as a robber fly.
Jeff Skevington (an entomologist at Agriculture and Agri-food Canada) added: “The robber fly looks like Laphria thoracica to me. They use their camouflage as protection from predators but also in a more aggressive way to hunt bumble bees. Nice that you got to see this!”
Try Googling Laphria thoracica and you will be amazed at how much this fly looks like a bumble bee. In the photo below, you can see that the robber fly’s eyes are too large for a bee, and I assume it has quite different mouth parts, but those are not features easily seen while these creatures are flying around.
Photo from BugGuide, showing identified Laphria thoracica preying on a Bombus sp.
Kudos to Berit for her observation skills and quick work with her cellphone camera.
We have one (or more) visiting our gardens this year. I, too, thought a bee was preying on a Japanese beetle and went online to find out it is a good robber fly. Fingers crossed it continues that activity and leaves the bees alone!!
Didn’t mean to write “good”!! I have no idea other than they are another pollinator.
Good morning,
I am so glad you posted this, I was at Lowes looking at flowers and what appeared to be a bumble carrying another bumble appeared. I was at a lost, I had never seen anything like this and I am always photographing honeybees and bumbles a like.
I actually have a photo, I dont think it is as good as the one posted, the position in which the bumble is carrying the other is almost like how a mom carries a child in a chest rig.
After reading your post, am going to take a closer look at my photo.
Cathy,
I hope you are well. Thank you for sharing about the robber fly eating Japanese beetles, I have a ton they eat, I have tried everything to get rid of them. The Japanese beetles eat everything, my roses, crepe myrtles and even my young willow trees.
Thank again Cathy for posting, I appreciate you. Many good blessings to you.