American Oil Beetle

Asked November 6, 2020, 12:01 PM EST

Hi, I have found 8-10 of these recently. I am still trying to determine if they came in some boxes my sister had out in John Day and Depoe Bay or if they are thriving on my rural property in Clackamas county. I did some research, but I am unable to determine what level of concern I should have and what action I should take. Can someone provide some regional advice? Thanks! Cindy

Clackamas County Oregon

2 Responses

Oil beetles of the genus Meloe, are often encountered in the 3 metro counties. The beetle in your image is a male.

That said, I will attempt to contact a faculty person who is more familiar with these beetles.The next response you receive will offer more information.

Hello Cindy,
I'm afraid that I am not familiar with these insects.

The PNW Insect Management Handbook also has some management info: http://pnwhandbooks.stage.extension.oregonstate.edu/insect/bee-protection/alkali-bee/alkali-bee-black-oil-beetle

You might want to submit a sample to the OSU Insect ID clinic. The entomologist there might be familiar with this insect and could perhaps provide more resources.
https://bpp.oregonstate.edu/plant-clinic/insect-id-clinic

This MSU pub has some management info: https://www.canr.msu.edu/news/blister_beetles_handle_with_care

There are a wide range of species, so I'm not sure if these resources from other states will be much help. These pubs seem to mainly discuss other species, neither of them provide local info, or management info.

https://extension.umaine.edu/home-and-garden-ipm/fact-sheets/common-name-listing/blister-beetles/

http://entnemdept.ufl.edu/creatures/urban/medical/blister_beetles.htm

I'm sorry I couldn't be more helpful, but I hope this at least helps your research.
Regards,