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Owls feed early in the evening and regurgitate a single pellet approximately 20 hours after eating. hawks, eagles and other raptors that swallow their prey whole Some Owl species will partially pluck bird and larger mammal prey. no crop
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Owls feed early in the evening and regurgitate a single pellet approximately 20 hours after eating.
hawks, eagles and other raptors that swallow their prey whole • Some Owl species will partially pluck bird and larger mammal prey.
no crop • sac in the throat that serves as storage for food for later consumption • 2 parts to stomach
How do Owl Pellets form? The protein enzymes and strong acids which occur in the digestive tract of raptors do not digest the entire meal. The relatively weak stomach muscles of the bird don’t break the bones so most are found whole.
The owl pellets that you will be examining in this lab have been collected and STERILIZED from common barn owls. • YOU SHOULD STILL WASH YOUR HANDS THOROUGHLY WHEN WE ARE FINISHED EACH DAY!
OWL PELLETS AS MICRO-ECOSYSTEMS • clothes moths • carpet beetles • fungi • The black spheres about the size of periods (.) that are found in the pellets are the droppings of the caterpillars. • The larvae metamorphose near the surface of a pellet in cocoons made of fur.
Science Project Journal Owl Pellet Survey/Regional Variation Inquiry This is a 3-day project after which you will create a research portfolio that will include the following: 1. title page 2. background information 3. materials and procedures 4. detailed dissection notes complete with sketches and measurements mass of pellet length and width diameter 5. 2 bone identification cards * the most complete skeleton neatly glued to the card and labeled * all other bones neatly glued to the card and labeled 6. Questions, Observations, and Conclusions page neatly filled out 7. compiled class data 8. project assessment
What you’ll turn in This must be neatly organized in a 3-prong folder or small binder. The bone identification cards must be in plastic sleeves. The entire project will be turned in for a test grade worth 100 points at the completion of day 3. Tues. 1/12 Day 1: background/introduction and procedures owl pellet dissection with dissection notes and identification Questions, Observations, and Conclusions Thurs. 1/14 Day 2: assemble bone identification cards compile class data/data analysis Tues. 1/19 Day 3:assessment & turn in portfolio
Use bone charts to identify bones and prey. Microscopes and hand lenses will help.
Sample notebook entry Observations of non-bone material: light gray fur, fur not dense, 2 thin white feathers on outside, few pieces of straw found outside