Bone + Specimen Processing Tips and Resources
Want to start making your own bony creations? This is a collection of helpful tips and resources gathered from my own experiences and around the web.
Know what is legal to own or collect in your area!
In North America, the Migratory Bird Treaty Act protects virtually all wild birds, their nests, eggs, and feathers. There are a few exceptions for non-native birds like the rock dove and European starling, but you need to be absolutely sure of your identification. Domestic species like chickens, peacocks, parrots, etc, are fine to use.
Other species may be illegal to own or collect on a state-by-state basis. In the US, your state’s Fish and Wildlife Department or Department of Natural Resources website is probably the best bet for more information.
Links: Groups, Blogs, Websites
Groups
Skeleton Cleaning
http://www.jakes-bones.com/p/how-to-clean-animal-bones.html?m=1
“Vulture Culture” masterpost: https://unofficialvulturecultureproblems.tumblr.com/post/155850535400/hiya-im-really-curious-how-to-get-into-vc-ive
“Oxidation method” using ammonia and hydrogen peroxide: https://www.theboneman.com/skeletoncleaningoxidationmethod
Wet Specimens
Preserving with formalin: https://lsa.umich.edu/ummz/herps/collections/preservation-techniques.html
Preserving with hand sanitizer: https://www.reddit.com/r/vultureculture/comments/dhytex/tried_using_hand_sanitizer_to_preserve_some_dead/
My Experiences
Whole carcasses:
Plastic tub + anthill: I put a couple of run-over turtles in my backyard under a plastic tub with a brick on top. I positioned everything near an ant nest and forgot about it. 6 months later, things were mostly clean but difficult to whiten. If I were going to do it this way again, I might put down some cheesecloth or a window screen first to minimize bone loss. There was a noticeable smell for a couple of weeks.
Rot pot: I skinned and gutted a rattlesnake and then put the carcass in one of those big Costco-sized plastic containers you get peanut butter pretzels in. I filled it with moistened dirt to cover and shook every few days (I left the lid on but slightly loosened at first – I tightened it after a few weeks. I left this one for probably 9 months. It was completely clean but hard to whiten and the skull got crushed at the bottom under the weight of the dirt.
More rot pot info here: https://blackbackedjackal.tumblr.com/post/140993897399/rot-pot-review
Mostly-Clean Carcasses
Keep in warm (not boiling) water with some washing soda (made by Arm and Hammer, find in the laundry aisle). You can also make your own washing soda by spreading ~1/2″ of baking soda on a cookie sheet and baking at 400 degrees F for about an hour, stirring 1-2 times.
DO NOT USE BLEACH OR BOILING WATER – it will ruin the bones.
For small bones I use a salsa jar (sealed) with a couple tablespoons of washing soda and warm water on an electric candle warmer.
For larger bones I use a crockpot on the keep warm setting. If a bone is too long to fit, you can do one half at a time with the lid open, but you have to keep an eye on it because the water will cook off more quickly.
After a few hours, dump the water outside and rinse off the specimen. For small skeletons, you’ll want a cheap mesh strainer from the dollar store to make sure you don’t lose anything.
Repeat this step if needed. A tiny bit of tissue is okay but you want them pretty clean at this point.
If you have a skull, make sure you get all the brains out!
For a BIG skull (like a cow or bison), it might make sense to do the anthill method first. I had some weather-cleaned skulls that I put in a tub of warm water and left in the summer sun. I changed the water and sprayed the skulls down with a hose every day.
I’ve found that washing soda takes care of most of the bone grease, but if you find that your bones are still yellow and/or smelly, you can soak them in acetone (use gloves, goggles, and caution) or ammonia. Replace when it gets cloudy – when it stays clear, the grease is all gone.
Whitening Clean Bones
Put them in a container and cover them with salon-grade hydrogen peroxide (get at Sally’s Beauty Supply). Use gloves and protect face/clothing, this stuff will bleach and burn anything it touches!
H2O2 loses its effectiveness when exposed to light and air, so keep the object in a plastic sealed container in a dark place. Don’t use glass, as the H2O2 will off-gas as it breaks down any remaining tissue and you don’t want to explode your container! I actually haven’t had any issues with this, but I do make sure not to screw the lid on too tightly.
If it’s something big, the H2O2 also comes in a gel formula you can brush on. If you go this route, seal it in a plastic bag and put it somewhere dark. I did this with a bison skull that worked okay.
You could add whitening powder to the H2O2 but I haven’t tried this. A woman at Sally’s told me that lots of her customers use it for bones.
When the bones are white enough, pick out the bones with tongs or pour out the container thru your strainer (assuming they’re little) into the sink.
I will often use a funnel and pour the H2O2 back into the bottle so I can reuse it a couple of times. But pouring it down the sink won’t hurt anything. Don’t forget the gloves!
Rinse off the bones and spread them out on a (dedicated) dish towel to dry. I use tweezers to separate them and spread them out a little.
Wet Specimens
Wet specimens are preserved in some kind of fluid. The best and longest-lasting ones use formalin or formaldehyde.
I don’t have a lot of experience with wet specimens, but I have done a few. I’m sharing my experience here but I recommend checking out additional resources if this is something you want to try.
Because of cost, hazard, and availability, I’ve only used isopropyl alcohol or grain alcohol. The problem with this method is that specimen will degrade faster and the water tends to yellow over time. I wouldn’t use this method with anything bigger than a rat. I’ve successfully done this with a few small snakes, a skink, and a plains leopard frog.
If you can, I’ve heard that removing the organs and stuffing the cavity with cotton helps slow the degradation. My frog was too stiff, so I injected the cavity with alcohol before putting it in the jar.
Drying Out Mummified Specimens or Insects
For the most part, leaving them somewhere they won’t be disturbed is all you need. If you want to speed up the process, you can put them in a tray of mixed salt and borax inside a sealed plastic bag. Change out the salt and borax mix every couple of days. I have heard that this is a good method for rabbits’ feet and bird wings.