Barn Owl Investigation

By Alex BJ Period 6 code 2

Introduction

A few types of owls

Barn Owl Barred owl Burrowing owl Eagle owl

Elf owl Great horned owl Great grey owl

Common Barn Owl prey types

Vole Pocket Gopher Mouse Shrew

Rat Songbird Mole Bat

Comparative question

More birds are eaten by barn owls in the southern U.S.A.

Are more birds eaten by Barn Owls in the northern United States, or in the southern United States?

Prediction

Procedure

Pocket Gopher (skeleton)

Pocket Gopher (living)

Data tables (6th period)

Animal Vole Pocket gopher

mouse Shrew Rat Bird Mole Total

# found 49 10 2 1 0 1 0 63

percent 77.8% 15.9% 3.2% 1.6% 0% 1.6% 0% 100%

Types of prey animals found in Owl pellets

Number of Prey Animals Per Pellet

Prey Animals per pellet

1 2 3 4 5 6 7 8 and over

Total # of pellets in class

Total # of prey animals in class

# of pellets

1 8 5 4 3 0 0 0 21 63

Percent 4.7% 38.1% 23.8% 19% 14.3% 0% 0% 0% 100% 100%

Data tables (whole grade)

Animal Vole Pocket gopher

mouse Shrew Rat Bird Mole Total

# found 260 27 37 4 0 3 0 294

percent 77.8% 15.9% 3.2% 1.6% 0% % 0% 100%

Types of prey animals found in Owl pellets

Number of Prey Animals Per Pellet

Prey Animals per pellet

1 2 3 4 5 6 7 8 and over

Total # of pellets in class

Total # of prey animals in class

# of pellets

8 30 32 20 11 4 0 1 106 294

Percent 7.5% 28.3%

30.2% 18.8% 10.4% 3.8% 0% .9% 100% 100%

Data table (whole grade extended)

Average # of prey animals per pellet (mean)

Type of prey animals contained by most pellets (mode for grade type of animals in owl pellet)

Number of prey animals contained by most pellets (mode for grade # of prey animals per pellet)

Lowest to highest # in one pellet (range)

2.72 0 None 7

Graphs for grade

Comparative question Graph and Data table

# of birds eaten in Northern United states by Barn owls (average)

# of birds eaten in Southern United states by Barn owls (average)

11 11.5

Discussion

Conclusion