Science Kids - My Inner Owl

Owl Pellet Dissection

Essential Questions and Answers about Owl Pellet Dissection

Learning about animals is a fun way to connect with the world we all share. Studying the diversity and interconnectedness of other species helps us to understand how we fit in the web of life. Sometimes we can learn by direct observation, and sometimes we need to use our intellectual curiosity to dig a little bit deeper. Either way, it is more fun to actively participate in our discoveries than it is to merely listen to others retelling of their experiences and knowledge. Owl pellet dissection is a great example of how we can do so.

What is an owl pellet?

Owl Eating Habits

Owls are carnivorous birds that feed on small creatures such as rodents, insects, and other birds. Unlike most birds of prey, they usually swallow their meals whole, rather than ripping them to bits with their beaks.

Owl Anatomy and Digestion

The digestive system of most birds includes a crop, a pouch-like structure for storing food after swallowing it until it is ready for digestion. Owls lack this body part, and instead, their food goes directly to the gizzard, where it gets sorted and processed as if it went into a finely-tuned machine.

Soft tissues like organ meat, muscle flesh, fats, and skin are useful for the owl’s energy and nourishment needs, and therefore are absorbed into the owl’s body, with a small amount finally going to waste and being ejected as urea, a bird’s equivalent of excrement. It is the whitish, pasty substance that birds expel or what most people might call “bird poop”, and it comes out from the bottom end of a bird.

But what about the hard tissues that the gizzard is not equipped to digest? Fur and the hard body parts of small creatures like bones, teeth, feathers, beaks, claws, and insect shells are not digestible, and could pose a potential hazard to the owl if they were to be processed all the way through the digestive tract to be flushed out with the urea.

Nature’s Answer

The infinite wisdom of nature has devised a solution for the owl and has designed its body to reject the parts that could spell danger for our avian friend. The gizzard compresses these leftovers into a pellet that is compact enough for the owl to expel back up the esophagus and out through its beak, a process known as regurgitation. In the case of owl pellets, regurgitation is also known as casting. Perhaps you have witnessed your pet cat coughing up a hairball. The owl’s process of casting a pellet is very similar to that.

Why Would We Want to Dissect an Owl Pellet?

Why would we want to dig into something similar to owl vomit? After all, isn’t it disgusting and morbid to rummage through the remains of some poor little beast that was unfortunate enough to become dinner for an owl? Perhaps on the surface it might seem so, but there is much interesting information to discover in those compact little meal-remnants!

Learn About Owls

The most obvious reason for studying owl pellets is to teach us about owls. In the classroom, students get to play Sherlock Holmes and unlock the mysteries hidden within. It’s an opportunity to explore firsthand exactly what is inside the casting and to learn about the bird that provided it.

Boy With Magnifying Glass

Kind of Prey

Since owls swallow an entire animal without chewing or rending it, the bones usually remain intact, which simplifies identifying what kind of animal or animals were in the owl’s nightly buffet. Looking at the shape of the skulls and other bones, as well as measuring them can tell us quite a bit about the meal. Even bird identification bands have been discovered inside owl pellets!

Kind of Owl

Along with kind of prey consumed, the size, shape, and texture of a pellet can provide information. Different kinds of owls produce different kinds of pellets. The texture, shape and varying degrees of compactness can all provide clues as to who heaved up the casting in question. For example, Barn Owls, whose pellets are the most commonly dissected, create pellets that are medium-sized, usually dark in color, smooth-textured, and generally cylindrical or barrel-shaped.

Size of Meals

Although we might logically conclude that the size of the pellet coincides with the size of the bird that gagged it up, that is not always the case. Large owls sometimes eat small prey. The size of the pellet can tell us the size of the meal that was consumed. A large casting might contain a single larger prey animal or several smaller creatures, which reveals something about the feeding behavior of the individual bird. Each pellet corresponds with a single feeding period, and usually owls produce one or two of them daily.

Learn About Ecosystems

The less obvious, but equally important reason for dissecting owl pellets is for scrutinizing the environment that contains the owl. When we open a casting it can also open a whole world of understanding about the ecosystem in which the owl spends time. Scientists study assorted pellets found within the same geographical area to gain knowledge about the various life forms living in the same vicinity, also known as the species diversity of the region. Studying owl castings reveals quite a bit about the food chain for kids and scientists alike!

How Can I Get Started?

Now that you understand the benefits of dissecting owl pellets, you might wonder how to get the materials you need. Where can you find owl pellets to dissect?

The Great Outdoors

You could go out to the forest and forage for owl hangouts to inspect for evidence of their meals. However, that could prove pretty challenging for most people who do not know where to search for owls. Additionally, owl pellets in the wild can harbor some nasty pathogens, or infectious materials that can be very dangerous for humans to handle. It’s seriously not advisable for budding scientists to touch owl castings found outside in the natural world. Leave that to the professionals.


Best Sources for Owl Pellets

So if you’re not going to go on a journey to find them in the woods, where can you source owl pellets to dissect? You could go to the local owl pellet store on the corner, but since that doesn’t exist in most neighborhoods, your best course of action is to consult the internet.

Believe it or not, numerous online retailers are available to help you in your quest to access owl pellets. Just do a quick Google search for “owl pellet dissection” and hit the “shopping” tab on the search page and an array of choices will magically appear.

Owl Pellet Dissection Kits

As you peruse the various options available for sale, you will notice that not only can you buy owl pellets online, but you can also purchase an entire owl pellet dissection kit containing all of the supplies you will need to put you on the road to owl casting discovery nirvana.

Barn Owl In Flight


Commercially available owl pellet dissection kits typically include similar items. Of course, they contain owl pellets, usually those generated by Barn Owls because those are generally easier to locate. The castings sold online are sterilized for the safety of everyone who handles them, using either heat or chemical methods.

Equipment and Supplies

Kits additionally contain dissection tools such as forceps, probes, needles, and tweezers, all of which are useful for manipulating the tiny innards of owl pellets, like mouse bones. Small containers for separating and categorizing the treasures recovered from within the castings may be integrated into a dissection kit, and some kits also incorporate safety equipment like gloves and goggles, since sharp tools are involved.

One of the most crucial parts of an owl pellet dissection kit is the identification sheet to help scientific sleuths identify common items found in an owl casting. Although most kits don’t come equipped with a microscope, having one available can add an additional layer of fun discovery to the identification process.

Little Scientist

Nature’s Treasure Chest

Regardless of the common reflexive reaction of revulsion many people experience when first presented with the idea of owl pellet dissection, most discover that the activity is fascinating enough to overcome this initial response, quickly becoming enamored with the process of unearthing the wonders of nature. Some individuals even go a step further and try to reconstruct the skeletons of the tiny animals contained within a casting. Dissecting an owl pellet is like opening Mother Nature’s treasure chest. What are you waiting for?