Owl Pellet Dissection

Reprinted from The Wild Times Teacher Connection v2n1, Fall 1996.

An interesting way for children to gain some insight into the adaptations of raptors is by examining owl pellets. All birds of prey produce pellets from the indigestible components (fur, feathers, bones, exoskeletons, etc.) of their diet. This material is formed into a pellet and coughed up. Once on the ground insects and microorganisms work on the pellet to decompose what remains. Through the dissection and examination of pellets it is possible to identify what the prey species are. By examining several pellets from a common source it is possible to hypothesize the variety of prey animals and preferences of different species.

video by Michael Wilkinson

We dissected owl pellets and found the bones and skulls of animals the barn owls had eaten. We found starling, vole, mouse, and shrew skulls. In our pellets voles were the most common. We think this means that voles are the most common prey where these owls live.
-Bank Street Environmental Science

Materials

owl pellets, tweezers, hand lenses, dissecting probes, small containers (petri dishes, sandwich boxes, film cannisters), skull and bone identification charts, writing and drawing paper, pencils, stereomicroscopes (optional)

Procedures

There are two ways to dissect owl pellets, dry or wet.

With dry dissections simply use the dissecting probe to carefully scrape and pick away the fur and feathers from the bones and skulls.

In a wet dissection, soak the pellets in a small container of water for a few hours. Then carefully pick out the bones and skulls.

My students prefer a combination of the two, removing large pieces dry and soaking them in film cannisters to completely remove the fur and feathers. Use a bone and skull identification key to determine what animals have been eaten. Teeth are especially useful in the identification process. Mice, voles, and shrews are common finds in an owl pellet and each has a very different type of teeth.

Resources

Owl Pellets

Pellets can be ordered through most of the science supply houses like Science Kit & Boreal Labs, and Carolina Biological. They can also be collected in the wild by exploring the ground around known owl perches.

Dissecting Supplies

Tweezers, hand lenses, petri dishes, and dissecting probes can be ordered through science supply houses.

Plastic sandwich boxes are convenient containers to keep a dissection in progress protected. Used for take out food, they can be found at a local deli or restaurant.

Books:

Discussion of owl pellet dissection and bone and skull identification chart.

Photographs of skeletons and focus on different structures and adaptations of skulls.

Submit your own curriculum plans or resource suggestions to The Wild Ones for publication.

Return to The Wild Ones Curriculum Index