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 Owl
Sound is provided by
Ohio State Parks, and is the call
of the Great Horned Owl
Owl Pellet
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Dissecting an Owl
Pellet |
Who-o-o are you?
| Owl Masks
| Owl Links
Owls, Food Webs, and Energy Cycles
 As
we study
biomes,
ecosystems,
habitats,
biodiversity,
adaptations,
food chains,
food webs,
and the
energy cycle,
it is interesting to read literature on those topics. We read
picture books and the novel
There's an Owl in the Shower,
by
Jean Craighead George.
We learn about the
spotted owl's
feeding habits, its life in the forest, and the controversy that
occurs when the choice to protect endangered species competes with
mankind's need to earn a living. We conclude this study by
dissecting an owl pellet. First, we discuss what an owl pellet is,
and what might be discovered by finding out what is inside.
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 What are owl
pellets?
*This
explanation of an owl pellet is from
Carolina's Website
What are owl pellets? The
pellets that we study in the classroom are the end products of an owl’s
digestive process. Pellets are also made by other raptors (birds of
prey), but those made by owls tend to be the most complete, and
therefore the best for classroom applications.
 Owls swallow the prey head first, placing it in the beak and
positioning it with the talons. Quick, upward thrusts of the owl’s head
and neck start the meal through the mouth and into the smooth, flexible
esophagus. The owl’s esophagus leads to a glandular stomach where the
prey comes to rest. The glandular stomach is similar to the crop found
in grain-eating birds, but instead of simply holding grain that will
later be ground by a gizzard, the owl’s glandular stomach is a digester
used for dissolving and separating the parts of the prey. The glandular
stomach is only part of the reason owls can eat like they do—that is,
bones and all. The carcass of the meal protects the owl’s throat from
sharp bones on the trip down, but eventually the bones must be brought
back out. Since owls have no teeth, the bones cannot be ground up to
pass through the intestine as in coyotes, bobcats, and other carnivores.
Instead, only the fleshy portions of the prey are broken down and passed
through a second stomach, the muscular stomach.
The muscular stomach acts as a strainer by catching the bones, claws,
scales, hair and/or feathers of the prey. The fleshy, digestible parts
continue beyond this lower stomach and through the intestine where water
and nutrient absorption takes place. The strained, undigested materials
left behind in the glandular stomach must eventually leave the owl the
same way they came in, through the mouth. But loose bones might get
lodged in the owl’s throat when regurgitated. To prevent this, the
stomach presses hair around the bones and forms a slick bolus. Muscles
along the esophagus reverse the direction used in swallowing. With a few
head lunges and stomach contractions, a soft package filled with bony
remains is expelled from the owl’s mouth.
This is what we call an owl pellet.
* NOTE:
There
are many resources for buying owl pellets. Here is the one I use:
Carolina.
I provide this information here not as an endorsement, but rather as
reference for other science teachers wanting to bring this activity
to their classroom. A search on "owl pellets," will yield many
resources for buying owl pellets.
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Dissecting owl pellets
We begin the dissection
by measuring the pellet's weight and size, and record that
information in our lab notes. Next, we dissect the pellet, pulling
the fur away from the bones, delicately so that we do not miss or
break any of the bones inside it.
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Who-o-o are you?
We really want to know..
Once we have all the fur pulled away from the bones, we become bone
detectives. We begin sorting the bones by type, using a
chart
that helps us identify them. Next we use another chart to determine
the placement of the bones so we can reconstruct the skeleton of the
animal. Finally we are able to identify the animal (prey) that
became food for the owl (predator). The skull and jaw bones are the
biggest help in making this identification.
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Owl Masks
    
Create an owl mask using
your own idea, or you can look at some of the ideas online.
Whooooo are my students behind these masks?
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 OWL LINKS
Activity Record Sheet
Record the results of your owl pellet investigation.
Carolina: The Seret World of Owls
Explains using owl pellets and
provides many related links. This site also provides an
opportunity to purchase pellets and other lab aides.
Dissecting Owl Pellets
Scholastic offers information for dissecting owl pellets.
Food Webs
Explore related links about food webs.
Ohio Department of Natural Resources
ODNR's site on barn owls.
Ohio Owls
The Great Horned Owl
is featured in this Ohio Parks article with resources.
Owl Food Chain
This
Government of Alberta site has a great graphic showing the owl's food web
and other links.
Owl
Pellet Activity
Another explanation
of doing the owl pellet activities.
Owl
Brand Discovery Kit Lab Demonstration
OBDK presents a step-by-step walk-through of a
science lab dissecting owl pellets. Other links on the site provide
an opportunity to purchase pellets and other lab aides.
Owl Pellets
Activities using owl pellets.
Pete's PowerPoint Station
List of Online
PowerPoints on Food Chains and Food Webs
Rubric Ideas
Spotted Owl
More information about the Spotted Owl.
Virtual
Owl Pellet
Kidwings provides this EXCELLENT and FUN virtual owl pellet resource! Select a species of
owl or click on a picture of a pellet. Under "Teacher Resources" there
are additional resources, including owl coloring pages.
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