The Owl Pellet Investigation
A class dissects owl pellets-the undigested parts of prey that owls cough up. In one pellet, students find the skulls and bones of three different small animals: two skulls with long, sharp front teeth and one skull with flat grinding teeth. They also find fur and tiny feathers. The students know owls are predators that swallow prey whole or in large pieces. They want to build an explanation of what this owl ate and how the owl fits into the food web of the field near the school.
1. Use the evidence in the pellet to describe what the owl likely ate. Explain how each piece of evidence supports your answer.
Read the worked answer
The owl likely ate at least three small animals, probably two rodents and one bird. Evidence:
- Two skulls with long, sharp front teeth suggest gnawing animals such as mice or voles (rodents), which eat seeds and plants.
- One skull with flat grinding teeth suggests an animal that grinds plant food, consistent with a different small mammal or possibly a plant-eating animal.
- Tiny feathers suggest at least one prey animal was a bird.
- Fur supports that mammals were eaten.
The bones, fur, and feathers are undigested parts, which is why they appear in the pellet. The owl swallowed prey in pieces, and the hard parts it could not digest were coughed back up.
2. Draw a simple food chain that includes the owl and the prey found in the pellet, and explain the owl's role.
Read the worked answer
A possible food chain: seeds and plants → mouse (rodent) → owl. A second branch: seeds/insects → small bird → owl.
The owl is a predator and a consumer. It eats other animals (mice, birds), so it is a carnivore. In the food web, it sits at a high level because it eats animals that themselves eat plants or seeds. The owl gets energy from its prey, and the prey got energy from plants. The pellet shows direct evidence of the owl's diet and its role as a predator in the field food web.