July 2025 Natural Mystery Answered

Last month's natural mystery was, in a word, messy. The tracks are atypical, and the loose sand obscures some of the details. But a number of you recognized these prints in spite of the challenges. Congratulations to Aimee Heavey, Blake Southard, Erin Anderson, Nancy Groeschner, and Robert Daun who correctly identified the species that left these prints. An extra shout-out to Greg Schayes who not only identified the species, but also pointed out what is distinctive about this particular individual.

These are the diminutive tracks of a juvenile Virginia opossum (Didelphis virginiana).

Blake kicks off our discussion with this succinct description:

“The sunrise front foot, overlapped by the rear foot with opposable thumb, forms a ‘hot mess’ as we learned from [CyberTracker evaluator] Michelle Peziol.”

Erin offers a similar summary of these tracks:

“When I first saw this print, I thought ‘that’s messy!’ Whenever I see a messy print, my mind goes immediately to opossum. Here, I see two separate prints with the hind print abutting the front. I see the radial sun beam pattern on the front print, indicating the wide splay of a possum front. Then I see the distinctive thumb print on the hind.”

Nancy notes that this distinctive, opposable thumb “makes it easier for the opossum to climb and hang onto trees and branches.”

Blake and Erin both remind us that messiness is a feature that can help us recognize opossum tracks. But this “hot mess” may also fool us at first glance. Robert walks us through a great example of this, writing:

"The first thing I saw was what appears to be a K-shaped track in the center of the photo. This led me to consider burrowing owl. But as I look more, these tracks become something else altogether—no longer a bird, but a marsupial!”

While identifying these tracks, Greg noticed that they were unusual for opossum. He explored this, writing: 

“My thought process started at opossum, but it is smallish. The small size was confusing, until I realized that it is the time of year where young are out on the land making tracks too! The splayed toes on the track below the ruler at the edge of the frame also look like an opossum front and are much bigger and more typical for an adult size opossum. Which led me to conclude that this is a young opossum traveling with its parent.”

Exactly right. If you haven't already notice it, take a look at the tiny “sunrise” of this juvenile’s front track compared to the front track of the fully grown adult (most likely mama) at the bottom of the photo. The tracks just above and to the left of mama's front track are the left side tracks of this same juvenile. Note the extremely short step length and wide trail of this juvenile as it learns to use its legs to navigate the world.

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