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Robles, M. Elena Kenwood Academy
5015 S. Blackstone
Chicago, Il. 60615
1. Discover and mount the contents of an owl pellet.
2. Relate the owls' eating habits with other animals (snake, cow, human).
3. Relate the contents of the owl pellet to the human skeletal system.
4. Discuss the food web, population control.
Materials (per lab group)
owl pellets forceps or toothpicks
3 dixie cups or beaker holepuncher
hydrogen peroxide(optional) a. bone sorting chart
paper (white) b. skeletal mounting
water c. bone identification
glue d. procedure
precut cardboard template e. homework
bleach (diluted) f. key of skulls
various skeleton models placemat (tray or paper)
metric ruler 1 liter bottle
overhead projector plastic owl
Soak 1 liter bottle in hot water to remove label and base (this can be done
at home). Cut bottle just below neck so that it fits snugly inverted in the base.
Test cardboard for proper fit inside the bottle. Place owl pellet on the
placemat. Gently separate bones from fur (soak in hydrogen peroxide for one
minute if pellet is too dry). Place bones on bone sorting chart (make sure you
have double of each bone, and one skull). Get teacher's approval. Soak bones in
diluted bleach to clean and whiten the bones (soak only three minutes). Get
skeleton layout sheet. Arrange bones on layout sheet. Get teacher's approval.
Transfer bone layout onto cardboard. Get teacher's approval. Glue bones to
cardboard. Use holepuncher to get circles for labeling of bones. Glue labels to
cardboard near bones. Cut white paper to fit backside of cardboard (to be used as
key for display). Make key for bone display using the bone identification
handout. Glue key to cardboard. Place completed bone display into inverted 1
liter bottle which rests on the original bottle base. Hand in for grading.
Begin the lesson by talking about the owl characteristics and its habits. Pass
out the owl pellets and discuss the physical characteristics of the pellet. The
students will be asked to measure their pellet and data will then be compared. Have
the students gently pull apart the pellet. Students will share discovered contents
from the owl pellet with the class, through a visual display on the overhead
projector. By comparing the number and types of skulls found in each pellet the class
will follow into a discussion on the food web and population control. The students
will be able to identify their specimen by measuring and using the "key of skulls"
handout. Continue the owl pellet project by following the above procedure.
NOTE: This project may take five to seven classes to complete.
SOURCES:a. Mark Wagner, Kenwood Academy
b. Creative Dimensions
Bellingham, Washington 98227
OWL PELLET OBSERVATION
1. MEASURE THE OWL PELLET (IN MILLIMETERS)
a.LENGTH OF THE PELLET ___________mm
b.DIAMETER OF THE PELLET _________mm
2. IDENTIFY AT LEAST THREE PHYSICAL CHARACTERISTICS OF THE PELLETS - SMELL,
COLOR, TEXTURE, ETC.
3. WHAT DO YOU THINK IS INSIDE OF THE PELLET?
4. IN WHICH PART OF THE OWL DOES THE PELLET FORM?
5. WHY DOES THIS PELLET FORM?
6. AFTER OPENING THE OWL PELLET WHAT INFORMATION WAS ATTAINED?
7. WRITE DOWN ONE QUESTION THAT YOU WOULD LIKE ANSWERED BY THE END OF THE OWL