|Dermestid colony specimen preparation|
|Dermestid beetles belong to the family Dermestidae, also called carpet beetles or larder beetles. These beetles are commonly used by museums and taxidermists to prepare skeletal material. The CMSC has been operating a colony for the past five years, cleaning everything from a full emu skeleton, to brown bats, shrews, and everything else in between. the following are some hints and suggestions in order to keep a colony in operation.
1) GET A GOOD HOUSING! You do not want any "escapees" out of your colony. Although they are harmless to you and I, they are extremely damaging to any type of dried animal material, such as taxidermy mounts and natural history collections. Insect collections are renowned for attracting dermestid infestation. If you have ever made an insect collection as a child, then slid it in a drawer or under your bed and came back to it a year later and found nothing but dust in the bottom, thank dermestids! They are a museum pest, and must be handled appropriately if you are in the vicinity of anything you do not want damaged. We have fabricated a container from 3/4 inch plexiglass salvaged from hockey rinks. the lid is especially designed to fit in a stairstep fashion with the box to eliminate any chance for exit. Crawling up the sides is eliminated due to the depth of the box and the slippery nature of the plexiglass, as long as its kept clean. I have never noticed a larvae or adult any higher than an inch up the side. when a specimen is complete all obvious beetles are shaken off and the specimen is immediately frozen to kill any hidden passengers.
A ventilation hole is put directly in the middle of the lid and covered with mesh. Adult dermstids can fly, although I rarely see one flying in the colony, so it is important to keep an eye on your colony any time you have the lid off.
It is possible to use other containers for colony housings. Aquariums are usually the first considered, but you need to have a good fitting lid fabricated out of Plexiglass, and the dermestids will, over long periods, damage silicon joints commonly used to hold glass together. My suggestion would be to find a non-working dorm fridge turned on its back or small chest freezer. Cut a vent hole in the door and screen it. You then have a container with a good sealing lid and a fairly slippery inside. If you want more information about, or cost of Plexiglass colony fabrication, contact me at firstname.lastname@example.org
2) keep the colony dry. If your colony gets too wet, little white mites will begin to appear, and will take over your colony. This has happened only once to our colony, and although the mites do not harm the dermestids themselves, they irritate the dermestids to the point that they will stop feeding. we now keep our colony very dry, and lightly mist any material in the colony perhaps once a day.
3) You dont need anything in the colony except for cardboard! I have read alot of forum posts about providing cotton, or logs, or woodchips, or all manner of other "bedding" material. Throw all of that stuff away. cut corregated cardboard into pieces (4 inch by 4 inch approx) and throw them around in the bottom of the colony. Thats all they need! in the colony pictured here I put in maybe 20-25 pieces. The cardboard provides something for the larvae to burrow into to pupate, and also acts as a moisture absorbing material. When the cardboard starts looking raggy and floppy, take it out and put fresh pieces in. I clean out perhaps 80 percent of the frass from this colony twice a year. if the frass looks damp, your colony is heading for trouble.
4) Dry your specimens! Dermestids do not feed well on rotting meat, and the colony can begin to stink very badly, so I have found it important to dry out any material that is being introduced into the colony. I skin the specimen, remove all large portions of meat, remove the eyes and brains from larger specimens as they will rot before the bugs can get to them, and then I put the specimen in a fume hood overnight to dry it to the consistancy of what I compare to soft bite beef jerky. I suspect you could do the same thing by putting it in front of a fan in a dry climate. After some experimenting you begin to get a feel for how the dermestids like it. I prefer to have them on the dry side, and if I notice the dermestids taking longer than expected, I'll begin lightly misting the specimen in the colony, perhaps once a day. Don't overdo it, a little mist goes a long way.
5) Keep the colony warm. Dermestids, like most insects, are active in temperatures above 60 degrees F, and the colony works the best in temps around 70 to 80 degrees F. Dermestids will go through periods of slower activity, especially if you are bringing the colony indoors and outdoors with the seasons.
6) Don't get discouraged! Once you get a good colony going it almost takes care of itself. It will take many months from acquiring your beetles until the time you can prepare larger specimens, so start small. Run something the size of jackrabbit skulls for the first couple of weeks. As your colony grows it will be able to complete larger specimens in reasonable time frames. I prepped an entire emu skeleton, piece by piece, in about a month, elk skulls in two or three weeks, small songbirds overnight! I usually have two or three small specimens along with something bigger going at the same time. Be aware that the success of the colony will run in cycles. Some weeks you will not be able to put specimens in fast enough, and other times it will slow down for no apparent reason. Be patient!
|Dermestid colony housing|
|Great Horned Owl|
|The above specimens were all prepared by dermestids and full mounted by Guy A. Hanley, Curator of Collections, CMSC
If you have any suggestions of more information you would like to see here, please let me know! I will add more information and pics as I get it organized.