#dermestids

[pacificremains]

My thousands of tiny pets hard at work on a bearded dragon skeleton

[neuropteran]

[skull-hoarder]

Well, I'm doing a little experiment with this Mojave rattlesnake that I bought a few days ago.

Basically, I prepared it for the dermestids, removing skin and organs as usual, unlike the fact that at the end I fill it with plastic bags to give it volume, since I have noticed that they flatten quite a bit when it is just a carcass, which makes the skeleton look less natural.

So it is filled with plastic and wrapped in a thread, supported by pins and sticks, let's hope it dries well and without deforming

If it works I'll try to do the same with a Colombian rainbow boa I have in the fridge and maybe a ball python, I'll also try to get a better rattlesnake from a local breeder since this one was pretty broken from being roadkill, still I think it will turn out pretty well, I cross my fingers

[kedreeva]

I haven’t posted about them in a while, but the dermestids are doing well. They’re regularly cleaning up a decent amount of meat, and seem to be breeding well. They’re just so innocuous. I don’t really know what I expected, tbh. They’re good little beetles.

[wizardhecker]

making an immensely niche image where i reference both an old meme and an entomology thing, thereby making art only I will enjoy

[bonecorn]

WAIT PLEASE INFODUMP ABOUT YOUR DERMESTIDS!

I’m going on 11 years of vulture stuff, way back before i knew it was a thing people did.

Here’s a quick pic of my room from several months ago. There’s more stuff now but my room is messy so no pics. This shows maybe 1/3 of my collection from this angle and I’ll show more if you want.

Charles the human is plaster, don’t fret. Everything else is real.

Infodump about my Cleaning Beetles below!

Uhh my colony! Quick info! Demestids are nature’s cleaning crew for dead animal matter. Usually when you think of decomposition you think of maggots, which are fly larvae. They’re fine with rotting or unhealthy flesh, and will sometimes infest living creatures with open wounds (fly strike.) Generally, they’re gross. They smell bad, they look bad, and they Sound bad. Have you ever sat next to a deer being munched on by thousands of maggots? It’s like the world’s worst serving of rice krispies. They DO have a place and many vultures like them and affectionately call them “disco rice.” I’m ok with them and find them valuable members of the ecosystem, but I don’t love them.

I LOVE dermestids. They’re a cute little black beetle species with adorable larvae. They’re larvae are small, dark, and fuzzy like caterpillars. They do not like to eat rotting flesh, and will never eat anything living. Dermestids prefer fresh deads or dried deads, and tend to move in after the maggots have come through. These ones will stay with a carcass until it’s bones are clean, pupating, adulting, mating, and laying the next generation in the same critter. I had a fox whose entire insides were replaced with empty pupa shells it was really cool and artistically inspiring! It’s a really beautiful process.

My colony! It’s a wild colony that I’ve had for a couple years. I got a raccoon with dermestids in it and put it in a cage in the woods, and it’s been going ever since. I keep them fed with a steady supply of critters, removing the old ones and cleaning them up. Whenever I transfer bones from the cage to water for further maceration, I pick off and shake out as many as I can, then I dunked the skull for a second, bring it up, and scoop off everyone who was inside and now needs to abandon ship. I know I have plenty left but I don’t like killing even the smallest living things, so I rescue them.

I love them so much. When you start fostering something you get very affectionate toward it and want to keep it healthy and happy. I will often pick up critters I don’t really want just because my colony hasn’t eaten lately and I want them to do well. I have SO many dried squirrel feet for this reason.

It’s very meditative, actually. They don’t smell bad, they just smell like dead leaves or a log turned over to see the air. Their food smells musty, like old mummies if you’ve ever smelled that. Sometimes I go out there every day just to sit and watch them. I leave a spray bottle out there full of water, because hydration is important, especially in the summer. So I’ll head out there, sit down and see how everybody’s doing. Sometimes I’ll turn over the deads or rearrange them to get the part I want processed into the heart of the colony. They like eating things that are covered, so some critters are partially skinned for access and they use the hide as shelter. The fastest way to get them to process something is to put it in the center of a couple deads and lay another dead on top of it.

When everything seems good and they’re doing ok, I just sit there and mist them with water. they LOVE IT!!!! It’s so exciting and endearing to see a few bugs resting on the surface of a dried dead, and then everyone comes out to party when the water comes out. They’ll hang out around droplets and you just watch them stick their little faces in and drink up. Everybody moves around and comes out to play and you can really see how many there are. I get the whole colony hydrated to give them water and to make the dried deads palatable again. It’s a little harder for them to eat jerky than to eat soft flesh, so keeping it hydrated helps them eat faster. This is especially important for deads that have been skinned first, as they dry out quickly. Demestids can still eat the dried stuff, but it takes them longer, and some may move on to greener pastures if they feel they’ve done all they can. They’re perfectly fine with waiting for rain and they don’t need my water to survive, but I find it really helps them thrive.

My colony is completely wild, and I don’t do anything to keep them with me. They are free to come and go through the forest cage. In nature, when they’re done with a dead the adults move on to find a new one and stop laying eggs, and the skeleton is left to nature to bury and have the bones spread around by scavengers or weather. Mine have a steady supply of food, so the adults choose to stay, lay their eggs, and raise generation after generation in my back yard. I help them along and I cherish them, but I don’t own them. Some people have captive colonies where they control the humidity, temperature, food source, and health of their dermestids, but I’m just fine with my wild ones.

Earlier this year, they slowed down a LOT. I looked closely and found that a whole bunch of mites had moved in and were crowding out my dermestids and crawling all over them. This is a huge problem for domestic colonies, but for me, it’s just nature. I stopped providing deads and now my colony has moved away to find better things, and I’ll let nature clear up the mites and wait for them to realize there’s nothing more for them to eat. Once they’re gone, I just need to put out a critter and restart my colony to bring it back to its full glory.

Nature is wonderful and I’m so privileged I get to be a part of it. You can spend hours out there just watching and listening, and learning what it has to tell you. I adore my little bugs, but I’m alright with nature running its course. They’re free to come and go as they like.

I have a forest for a backyard, but you can have a wild colony if you live in the city and just know somebody with a patch of woods, prairie, or really anything wild. As long as you can set up a cage a decent bit away from houses to reduce smell, all they need is a dead thing to get started. For best results, find something dead and kind of dry looking and it probably has demestids inside it. You can’t always count on them spontaneously moving in, but it’s worth a shot! You also don’t need to mist them as they can take care of themselves.

I just love them so much. They’re so good to me and I’m good to them back. They’re adorable and sometimes finding a newly hatched or newly shed baby makes me so proud I cry.

I love them!!!!!!!

[carnegiemuseumnaturalhistory]

Bugs That Really Bug Us—Systematic Freezing of the Entire Collection in Invertebrate Zoology

With a collection of over 13.5 million specimens, some could say that the Section of Invertebrate Zoology “loves” bugs. We’ve amassed an enormous volume of arthropods (including bugs) in all shapes, sizes, varieties, forms, variants, and life cycles. We’ve preserved them to the best of our abilities, away from many of the activities and threats that would do them harm. However, one not-so-loved bug in our section is the dermestid beetle, a pest that threatens many museum collections worldwide.

In the taxonomic order Coleoptera, the beetle family Dermestidae is a group of about 500-700 species from all over the world and are sometimes known colloquially as “Carpet Beetles.” This holometabolous group has an especially destructive larval stage, feeding on dead animal or plant matter. An infestation of these beetles can easily wipe out a small collection, so to preserve the  integrity of our collection, we are ever vigilant in our efforts to prevent this irksome critter.

Figure 1. Dermestid frass under a moth specimen. At front center, a dead dermestid can be seen.

Dermestid beetles are relatively small, sometimes measuring just a few millimeters at their largest. Spotting them can be difficult; often, they’re only detected after damage has already occurred. Figure 1 shows their frass, a light brown/tan powdery substance left over from a feeding session. Other dermestid signs are their exuvial skins, shown in Figure 2. These are left behind when a larvae molts, typically growing larger each time (although some species in the genus Trogoderma have been known to molt backwards, growing smaller each time, if food is scarce).

Figure 2. A dermestid exuvia, shed once the beetle larvae molted.

While the dermestid beetle is certainly a resilient insect, there are a few ways to eliminate it; through severe cold or complete desiccation (i.e., 0% humidity). My predecessor used to freeze at-risk portions of our Holland Room in chest freezers, which reach only about -8°F. Up until last year, the most feasible option for our collection was to spot check and freeze at-risk areas, as well as freeze all specimens coming into the building, no matter the source.

Figure 3. A freezer cart loaded with Old Holland Drawers, inside the Kolpak freezer.

In April of 2018, the IZ staff began an extensive integrated pest management protocol involving the freezing of the entire pinned insect collection. This was the first time the section has attempted to methodically freeze all of its various parts and pieces. This massive undertaking took over 17 months to complete, and hundreds of hours of staff time, as we shuffled roughly 30,000 drawers in and out of our walk-in freezers.

Figure 4. A freezer cart left to thaw before returning drawers into the collection.

Beginning in the Holland Room, we systematically placed drawers onto freezer carts, shown in Figures 3 and 4. These metal carts can house 40 drawers per cart, one per slot. We arranged these carts to fit in our walk-in Kolpak freezers (a size akin to something like a restaurant meat freezer). These freezers reach down to -16°F, and live dermestid beetles in a drawer will perish at that temperature.  Once freezing is complete, dermestized drawers are cleaned prior to returning them to their place in the collection. We froze cyclically every Monday, Wednesday, and Friday, leaving drawers in the freezer for 2–3 days. After removing carts from the freezer, the drawers were thawed to prevent the introduction of moisture, which may damage the specimens, and they were put back into the collection in the same order they were initially retrieved. Maintaining drawer order is especially important in curated sections of the collection, as one proceeding drawer may contain specimens from the same group as the next, and so forth.

Although our protocol may seem straightforward, with all the different methods of storage in our section (See my blog on different Drawer Types housed here in IZ), freezing from one session to the next could entail a multitude of different drawer types, heights, and sizes. At our most productive, we froze 5 freezer carts at a time, moving 400 drawers per freeze day (200 in, 200 out). We concluded the freezing earlier this year on 13 September 2019, and we anticipate the next time we’ll start a complete freezing of the collection again will be in January 2021.

Catherine Giles is the Curatorial Assistant of Invertebrate Zoology at the Carnegie Museum of Natural History. Museum employees are encouraged to blog about their unique experiences working at the museum.

[xxbonegirl11xx]

I think I just?? Caught some dermestids?? ??????????? I had Barnabus macerating this past week, but apparently at some point his tub got knocked over and spilled. Thankfully he stayed in it, but some new friends joined him. There were of course maggots, adult flies, and a few other kinds of beetles some of which I believe to be dermestids. I righted the tub and put the lid on loosely, but I'm kind of tempted to just let them have at it and see what happens. OR, I could pour water in again and let the dermestids float to the top and capture them. I could POTENTIALLY start a wild colony, and if it fails due to the habitat or parasites then it's no skin off my nose. The main issue is that, from what I understand, not all dermestids are created equal. The dermestids in museums are a specific species which cleans the flesh but leaves the bone and ligaments intact (unless you leave it too long), but wild dermestids are typically more destructive - or its at least a wild chance as to what they'll do since they might be a different species. So maybe I should grab the dermestids, start a little experimental meatdog colony, and give them some scrap bones that I'd throw out anyway. Then I can assess how they treat bones without risking Barnabus. I can get better pictures of what all is in there if anyone wants them! But this is really out of my area, so any thoughts??