Many birds of prey - or raptors - produce pellets. Owls are best known for this practice, but some hawks, eagles, gulls, and other birds also produce pellets. The soft parts of their prey are digested in the stomachs of these birds. The fur, bones, feathers. and other hard items are not digested and form a pellet in the gullet of the owl. This pellet is regurgitated from the mouth and can be found under a tree, barn, or wherever the owl may have roosted that night. Owl pellets are made up of bones, teeth, hair, feathers, scales, or insect skeletons.
Owl pellets vary in size according to the owl's size, but they are generally oblong in shape and one-three inches in length. The pellets are dry and odorless. They do not contain any fecal matter.
You can often tell where an owl lives or hunts by observing what kind of animal skeletons show up in the pellets. For example, short-eared owls hunt in open fields at dusk, so their pellets contain skeletons of meadow voles, mice, and small birds. The bones of animals that live in the forest would not appear in a short-eared owl pellet.
You can investigate a food chain by dissecting and exploring a number of owl pellets and attempting to identify the animals whose skeletons are found in the pellets. Owl pellets are easiest to find in the winter when they stand out against the white snow background. Often an owl or groups of owls will use the same tree as a feeding site for many weeks. If you have a winter outing, you might encourage students to watch for pellets and save them to use in this exercise later in the year. Dry the pellets and store them in a container. Add a moth ball to control insect larvae living in the pellet.