Owl Owl Pellet Pellet

DissectionDissection

What is an Owl Pellet?

• An owl pellet is the feces that is regurgitate. Owl's cannot digest fur, feathers and bones, that is the main reason of regurgitation. An owl will still produce urea.

• Pellets range in size, it all depends on the size of the owl and the amount it has eaten.

Background• The owl pellets that will be distributed to the students come from

barn owls. Barn owls are medium sized owls with large heads and long legs. The size of the cranium is due to the enhanced sight sensitivity for seeing in the dark as well as the vast aural capacity enabling the owls to hear the faintest sound made by their prey.

• The barn owls are found all across the globe. They are mostly found in fields and pastures because of the increased rodent population, their favorite prey. All owls have an interesting way of dealing with their food. After digesting the nutritious parts of the small animals they eat, they regurgitate all of the undigested parts in a small pellet.

• The pellet is composed of bones, fur and teeth. Because barn owls don't tear their prey to pieces, there is always a complete skeleton of at least on rodent in every pellet. Every bone from the skull to the last tip of the tailbone can be found. A good observer with a little patience will be able to piece together the incredible skeletal masterpiece. sources: Human Body Module FOSS 1992 Edition 

Objectives

• This activity is designed to give students a "hands-on" interaction with the process of different animal digestions, the skeletal system, predator and prey anatomy and how its anatomy is tailored for its survival.

Bones to Look for.

Animal Lab Group Class Total Total%

Shrew 1 2.6

House Mouse 5.5 14.3

Vole 28.5 74

Deer mouse 3.5 9.1

Mole 0 0

Rat 0 0

Bird 0 0

Insect 0 0

Other 0 0

Total 38.5 -

Total pellets 10 -

Average/pellet 3.85 -

Produce Graphs

05

1015202530

Shrew

House

mou

se Vole

Deer m

ouse

Mole Rat

Bird

Inse

ct

Other

Series1

Produce Graphs

Shrew

House mouse

Vole

Deer mouse

Mole

Rat

Bird

Insect

Other

Create a Food web Using the following data

Eats Taken byGrass Converts Radiant energy Grasshopper, vole, deer

mouse, house mouse, Gopher, DDD

Seeds Converts Radiant energy beetle, vole, deer mouse, Gopher, songbirds, DDD

grasshopper Grass, Seeds Shrew, songbirds, DDD

Beetle Seeds Shrew, songbirds, DDD

Garter Snake Deer mouse, vole, beetle Owl, DDD

gopher Grass, seeds Barn owl, DDD

shrew Beetle, grasshopper, vole, deer mouse, house mouse,

Barn owl, DDD

songbirds seeds, grasshopper, Beetle Barn owl, DDD

Deer mouse Grass, seeds Barn owl, DDD

vole Grass, seeds Shrew, Barn owl, DDD

Barn owl ? DDD

Food Chain

Food web

Food web • An ecological pyramid is constructed

based on one of three types of data:– number of organisms– the amount of biomass – amount of energy.

• Each feeding (trophic) level passes 10% of its stored energy to the next level. – Therefore, if the producers had 10,000

units (calories) of available energy,– the herbivores would receive 1000 units,– the primary carnivores 100 units – the secondary carnivores 10 units.

-end

Extra credit

• Create a game using the previous data with the objective of creating a game (with explained rules) to teach about food webs and ecological relationships– Cards should be made

GrassEat:

Converts Radiant energy

Taken by:

Grasshopper, beetle, vole, deer mouse, house

mouse, Gopher, DDD

Virtual

• http://www.kidwings.com/owlpellets/barnowl/index2.htm

• http://www.cnr.vt.edu/forsite/owlpellet/josh/josh1.HTM

Sites Used for Pictures and References

• http://www.cnr.vt.edu/forsite/owlpellet/josh/josh2.htm

• http://www.eelsinc.org/id43.html

• http://www.scienceman.com/pgs/archive21_owlpellet.html

• http://cas.bellarmine.edu/tietjen/Laboratories/Owls2/owl_lab.htm