By Rachel Lee
Period 6
Code 9
Introduction
My Comparative Question and
Hypothesis
My hypothesis: If the diet of a Barn, Saw-whet, and Screech owl
were to be researched, then the Barn owl will eat the most variety of
prey animals because it is the largest among the three owls.
My Comparative Question: Which owl species eats the most
variety of prey animals, the Barn, Saw-whet, or Screech owl?
Procedure / Methods
First we received an owl pellet. Then we recorded the length,
width, height and mass of our pellet. We all started breaking the pellet
into small pieces and started to dissect. Later, I sorted my bones to the
ones that look alike and created the skeleton of my prey animal. After
this, we collected our data and created a comparative question with our
confirmed answer. Finally, from all that information, we created a
PowerPoint that I am showing you right now.
My Prey Skeleton
This is my prey
skeleton that is
(was) a Pocket
Gopher.
A Barn Owl’s Prey (few of many)
A Shrew
A Vole
My Data
Table 1: Summary of Individual Owl Pellet Contents
Prey animal found
Number of each
Bird
1
Pocket Gopher
2
Non-prey items found (if any)
None
Table 2: Types of Prey Animals found in Owl Pellets Period 6 Results:
Animal
Vole
Pocket
Gopher
Mouse
Shrew
Rat
Bird
Mole
Total
# found
49
10
2
1
0
1
0
63
Percent
78%
16%
3%
2%
0%
2%
0%
100%
My Data (Cont’d)
Table 3: Number of Prey Animals per Pellet Period 6 Results:
Table 4: Types of Prey Animals found in Owl Pellets Entire Grade Results:
Animal
Vole
Pocket
Gopher
Mouse
Shrew
Rat
Bird
Molde
Total
# found
260
27
37
4
0
3
0
331
Percent
79%
8%
11%
1%
0%
1%
0%
100%
My Data(Cont’d)
Table 5: Number of Prey Animals per Pellet - Entire Grade Results:
Table 6: Entire Class Statistics
Average number of prey animals
per pellet (mean)
Type of prey animal contained by most
pellets (mode for Table 4)
Number of prey animals contained by
most pellets (mode for Table 5)
Lowest to highest number of prey
animals in one pellet (range)
3
Vole
3
0-8
Graphs
My Comparative Question Data
(Data from http://www.allaboutbirds.org)
Type of Owl
Variety of Prey
Animals
Barn Owls
(Tyto Alba)
10
Saw-whet
(Aegolius acadicus)
34
Screech
(Megascops asio)
23
Barn Owl Food Web
Discussion
Conclusion
Thank You for Watching