Tuesday

Pickling a Snake

I have been doing a lot of work with the herpetology collections of late. The past two weeks have seen me pickling and tagging all kinds of neat critters including a  Mojave Zebra-tailed Lizard (Callisaurus draconoides rhodstictus), the first in our collection, and a Striped Racer (Coluber lateralis lateralis) with 10 eggs inside her. For your enjoyment here are the steps to prepare a snake for a herpetology wet collection- in this case another Striped Racer.

1. Freeze the critter- we do this to kill parasites and because we cannot always pickle them right away. Keep in mind that the longer they sit the freezer the more likely they are to become freezer mummies. This guy was only in the freezer for 5 days, but I did a few that were pushing it at 8 years.
2. Thaw the snake and massage it to remove and bends. Basically, be a chiropractor; pull, twist, and rub all the kinks out of its spine so it can be recoiled into a nice shape in the jar.

3. Sew its tags in. Because this is a snake the tags are sewn on rather than tied around a limb. The needle is inserted under the vertebral column- on the ventral side- then a square knot is tied on the dorsal side of the snake. Remember to use good quality cotton thread, a non-dissolving paper, and no-run ink. Our herps get a tag with their catalog and another with all their collection information. 

4. Pickle it! This entails injecting the body with formalin (10% buffered formaldehyde). For a snake this size I inject formalin every 1.5 inches beginning a few inches below the anus. As this snake is male a hemipenis had to be inverted via injecting fluid. NOTE! Inject lots of formalin around the gall bladder lest it rot and turn your snake green and gooey.

5. Massage the formalin around in the body cavity.
6. Coil the snake in the jar so the tags face the outside of the jar. Make sure the snake is not twisted around, is as close to the sides of the jar as possible, and its mouth is closed.

7. Fill the jar with more formalin. If the snake is floating there are air bubbles in it. If this happens massage them out, inject more formalin, and try again (this snake is under a Gopher Snake [Pituophis catenifer catenifer] to save space)
8. Admire your beautiful snake while you wait a week or so for the formalin to set.
9. After a week transfer the snake to a bucket of water. If the snake has no abdominal openings make small incisions on the belly to allow formalin out and water in. Allow to sit in water for a week changing the water every day or so.

10. Place snake into a clean jar and fill with low concentration ethanol.
11. After one week transfer the snake to a final jar, fill with clean 70% ethanol and place into the collections.
Here are some Tiger Salamander larvae (Ambystoma californiense) ready for shelving.

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