TRACK SOUVENIRS: Casting plaster animal tracks
Students make plaster casts of animal tracks found outside or create plaster imprints of animal track replicas. They gain practice observing the natural world closely, and create a memento they can keep without removing any objects from the natural world.
How to make plaster casts of an animal track. 2011. MyNatureApps. https://www.youtube.com/watch?v=Y4WTmgo4zeA
Cabrera, Kim A. 2001-2007. Plaster Track Casting Procedure. Beartracker.com. https://www.michigan.gov/documents/dnr/Track_casting_382484_7.pdf
Save Animal Tracks as Plaster Casts. https://www.startwithabook.org/content/pdfs/tracksplastercast.pdf
Mangor, Jodie. 2021. How to make a plaster cast of animal tracks in the snow. Scout Life. Boy Scouts of America. https://scoutlife.org/hobbies-projects/funstuff/151633/make-a-plaster-cast-of-animal-tracks-in-the-snow/
Included in kits unless otherwise noted
● Plaster of Paris (2-4 x 4 lb. containers)
● Jumbo craft sticks for stirring/mixing plaster
● Gallon size Ziplock bags for mixing plaster and water
● 1-2” wide strips of cardstock or manila folder material for forming a ring or collar around the track to contain the plaster
● clothespin or paperclip to secure the cardstock/paper ring
● Spray bottle
● School provides water for mixing with plaster and for use in spray bottle to set the track in snow before pouring plaster. 32 oz. Nalgene water bottle provided in kit should hold enough water for a couple of smaller tracks; a moose or bear track might require the whole bottle.
Refer to instructions in reference materials listed above. Note that different sources have different opinions and preferences for materials and methods. Try an approach that appeals to you! One thing to note is that if you are making plaster tracks in snow, it is worth lightly spraying the track with a fine spray of cold water before adding the plaster to help set the track. Also, mix some snow in with the water when mixing your plaster so that the plaster mixture doesn’t melt the track.
In case you aren’t able to find any good tracks to cast outdoors, you can make negative track imprints using the flexible track replicas provided in your kit. Your kit will contain either a) two caribou tracks and two wolf tracks or b) two wolverine tracks and two snowshoe hare tracks.
Follow these steps to make negative impressions of the replica tracks provided:
- Use the paper bowls provided to mix individual portions of plaster and water. A mixture of two parts plaster to one part water is generally recommended.
- Fill the bowl about two thirds full with plaster-water mixture and continue to stir using a craft stick.
- When your plaster and water mixture is a good consistency (like thick pancake batter), smooth the top of it with a craft stick.
- If you have access to cooking spray, you might choose to lightly spray the surface of the track replica before inserting it into the plaster.
- Then, firmly press the track replica face-down into the bowl of plaster. Allow it to sit, undisturbed, for approximately twenty minutes.
- After twenty-five minutes, lightly touch the plaster with your finger to test how dry it is. If it is fairly dry and stiff, attempt to remove the track replica from the plaster.
- Your result should be an imprint of the track – just like what you might find in the snow or mud if you found an animal track outdoors.
- Ideally there will be enough bowls that each student can make an imprint and take a bowl home; there is no need to remove the plaster from the bowl. They may choose to decorate the final product with paint or glitter or to add their initials, the date, and the name of the animal whose track they have cast.