Pellet Data Detective Lab (Graph + CER + Food Web)
Claim: What type of habitat does this owl hunt near? Evidence: Use at least 3 prey categories to support your claim. Reasoning: Explain how each prey type connects to habitat features (cover, edges,…
- No prep
Part A: Build the class graph
- Put the categories on the board: Voles, Mice, Rats, Birds, Shrews, Moles, Insects & Other
- Students build a bar graph from the counts.
- Add one sentence under the graph:
“What prey category dominates, and what might that suggest about the habitat?”
Part B: CER (Claim, Evidence, Reasoning)
Claim: What type of habitat does this owl hunt near?
Evidence: Use at least 3 prey categories to support your claim.
Reasoning: Explain how each prey type connects to habitat features (cover, edges, human structures, underground soil systems).
Part C: Build the food web (the “connect everything” move)
Start with plants/seeds/insects → small mammals → barn owl.
Then ask: Where does snow, grass cover, and edge habitat fit into this web?
Questions to ask
- Where does snow, grass cover, and edge habitat fit into this web?
Where it comes from
Winter (and early spring) has a funny way of turning the outdoors into a science lab. You don’t need a microscope. You don’t need a fancy field station.
Sometimes you just need a pellet.
In a study with Kim Regier, EdD (Department of Integrative Biology) at the University of Colorado Denver, students have been collecting data from barn owl pellets from OBDK since 2020. After 453 pellets dissected, here’s what showed up as the top prey categories:
Read the blog post ↗ What 453 Owl Pellets Can Tell Us About a Habitat · 2026-01-21
Workspace
Run it with your class
Set up the class, count what needs counting, write down what happened, then save it and take it with you. Everything here stays in this browser until you download it.
The class
Counters
Results table
Notes as you go
This activity has no numbered steps, so use the notes box.
Answers to the questions
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