“Hi Margriet,
I called you yesterday from the 16th/Oak community garden about a strange pest we found in our mason bee hive. They looked like larva with little red heads and were crawling over the cocoons in one of the trays. Do you have any idea what they might be from the attached images?
By the way I’ve read your book cover and cover and if I may be so bold I’d like to offer a small suggestion. Being a novice mason bee keeper I found it really hard to imagine and identify the pests you were talking about with the black and white drawings. Perhaps in future additions if budgets permit you could include actual photographs of the critters you describe? I’m sure the community at large would offer many for your book 🙂 In all other respects that book was invaluable!Â
I’ve also recently heard of people not using the bleach/water solution to clean cocoons but to use sand instead as an abrasive to remove mites. Have you or others ever tried the technique?Â
Many Thanks,
Maria”
Hi Maria,Â
Thank you for your pictures and comments. Â
 Scavenger type beetle larvae.  Note size in comparison withÂ
mason bee cocoon in upper right hand side of picture.

Cscavenger type Beetle larvae are reddish brown and can be recognized by their long bristles on each larval segment. |

- This pest is a carpet beetle (Page 90 Pollination with Mason Bees by M.D Dogterom. Â These beetles feed on pollen provisions and nest debris. Â Â
- Yes, a book in colour would be awesome. Â Like you mentioned, budget permitting. Â It is definitely in the works for a future edition.
- Yes, I have heard about the sand/abrasive technique to remove mites.  I have not used it myself.  I use a metal mesh as an abrasive surface to remove mites, and do a final rinse in bleach to remove any molds and parasitic fungi. Using an abrasive surface like a metal screen works very well. The sand is also used as an abrasive technique to scour mites from the cocoons. I prefer not to deal with sand and find this a definite advantage.
Margriet