1. The Barn Owl The barn owl is found all over America
The barn owl is found all over America
Owls hunt in open fields and roost in old barns or open abandoned buildings
Nocturnal – hunt at night and sleep during the day
Carnivores: They only eat meat

2. Predator vs. Prey Predator: hunt and kills
Predator: hunt and kills
They prey on a number of species that live in open grasslands, farmlands, and marshes
Prey: voles, shrews, deer mice, bats, rats, small birds, and insects

3. Roosting
During the day: barn owls roost in trees, rocky cliffs, and building around farms.
They will build their nest and “sleep” during the day in dark places

4. Owl Pellets
Owl Pellets are the indigestible remains of food eaten by owls
Instead of being excreted with the other waste materials (poop), the waste is regurgitated.
Regurgitate: spit up

5. Owl Pellets
Owl Pellets are a compact mass of hair, bones, teeth, claws, bird’s beaks, and chitinous remains of insects (body shells)
Lots of birds regurgitate! Over 300 species of birds have been found to produce pellets

6. Where do they put it?
Indigestible materials (fur and bones) are compacted in the stomach called a gizzard
The gizzard presses it all together and then passes it to the proventriculus
The proventriculus is a storage pouch until the bird it ready to regurgitate

7. Indigestible Items

8. How long does it take?
An owl will produce an owl pellet after most meals
An owl will eat two to four times a day
It takes approximately 6.5 hours for an owl to digest its food and then regurgitate a pellet.

9. What does dissecting tell you?
Dissecting an owl pellet can tell scientists what kind of diet the owls are eating
Feeding habits
Conditions of the ecosystem
Identification of prey
Owls swallow their food whole, so their pellets contain entire skeletons that can be studied

10. Prey: Voles Small rodents Blunt snout and chunky bodies
Small rodents
Blunt snout and chunky bodies
Their fur is soft and dull grey
Habitat – meadows, dry plains, forests, and marshy areas
Omnivores: plants, seeds, nuts, insects
Active day and night

11. Prey: Deer Mouse -------------------------------------
Small rodent
Abundant in North America
Habitat: brush, under trees, rocks
Deer like coloring of the fur: brown on top, white on bottom
Nocturnal: hunt at night
Omnivores: plants, seeds, nuts, berries, insects, human food
Population: Females can have a litter of 12 babies every 21 days! The babies will mature in 7 weeks and have babies too!!

12. Prey: Shrews Smallest of all mammals Thick fur
Smallest of all mammals
Thick fur
Insectivores: eat insects
Habitat: hide in dense (thick) vegetation (plants) near water and are seldom seen
They will hunt day and night

13. Dissecting Owl Pellets
The owl pellets have been autoclaved (cooked at high temperatures) and DO NOT contain any harmful bacteria or diseases
No gloves necessary
Lab safety: Wash your hands when finished with the activity

14. Dissecting Owl Pellets
Dissecting Method:
Carefully pick apart each pellet by hand
Hair and feathers are teased away from the bones
Lab instruments needed: dissecting probes, magnifying lens, paper towel, black paper

15. Dissecting Owl Pellets
A magnifying lens is necessary to examine the fine structures of teeth for final prey identification
Use the bone identification chart to determine the species of prey
Try to put the prey skeleton “back together again”

16. Dissecting Owl Pellets
Read the lab instructions carefully!
Dissect the owl pellet
Determine what prey the owl has eaten
Put the skeleton back together again
Answer the lab questions
Throw everything away
Wash your hands!