Insects and Spiders - native

Bumble Bees (Bombus spp.) on May 27, 2008

Submitter has sample

Description of specimen

extremely large, dying, bees. I have a small colony of honey bees living in a bird house(see picture). These bees are green pee size, docile, and very happy collecting pollen and bringing it back to the house. Today I found these huge bees crawling away from the hive, 3 living, one dead. I believe they are attacking the hive and being defeated, so far. I have lived in oregon over 30 years and never seen a bee this big (Besides the bumble bee). Sugar ants are eating the bee in one picture. another was crawling up the foundation of the house. The curled one I hit with bee killer. I am using a IPA soaked sponge and a jar to try and preserve another one.


What are these large bees? Are my honey bees in danger? Am I in danger? The large bees are continuing to arrive/pass through every hour or so, what can I do?

May 27, 2008, 12:08 p.m.

I have shared your photos with an entomologist at Oregon State University. As soon as we receive a response, I'll post it to the website. Thank you for your patience.

Lisa DeBruyckere
May 27, 2008, 11:45 p.m.

In the New Photo: The bee was already dying (crawling on ground) I put it in a jar with some Isopropyl alcohol and left it overnight. Photos of preserved bee are taken on 0.2" x 0.2" grid paper. These bees sound like a bumble bee when they fly by. Today I have not seen/heard any big bees, the little bees still seem happy in their little bird house.

May 28, 2008, 6:43 a.m.

Jeff, an entomologist at Oregon State University reviewed your photos and has confirmed that these are bumble bees (Bombus melanopygus), a common bee that is aggressive towards humans and commonly nests in bird houses, mouse nests, or the ground this time of year. You can access some additional information about this species at this website - Bumble bees were the featured "species of the month" in 1993 on this site.

This species of bumble bee is commonly known as the orange-rumped bumblebee, and is a species of bumblebee native to western North America from British Columbia to California and as far east as Idaho. They live in organized groups, with a queen, drones, and workers.

A September 2006 report for the California Department of Agriculture said this about competition between introduced honey bees and native bumblebees: "The negative effect of competition of food sources presumes that the availability of food sources is limited. In the case of introduction in agro eco-systems with a pollination deficit this would not be the case."

Here's another good website on native bumblebees:

Lisa DeBruyckere
May 28, 2008, 9:37 a.m.

I wanted to thank everyone involved in this project. I was very satisfied with the whole process and was very pleased with the response I received.
I am disappointed that my birdhouse hive of honeybees is now quiet. For 2 weeks the hive was buzzing with activity. Then something happened, because I no longer see any bees at all. I know if the hive mooved or was killed off by the bumble bees.

June 16, 2008, 2:22 p.m.