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Bloom’s Taxonomy and Owl Pellets(Bloom’s Verbs are in red)

Background—Students have been introduced to general ecology vocabulary in a previous lesson biotic, abiotic, autotroph, heterotroph, carnivore, herbivore, omnivore, food chain, food web, 10% Energy Law, population, community, ecosystem

Introduction—Students unwrap and examine owl pellets without being told what they are. They form hypotheses regarding the origin of the owl pellets. They write descriptions and measure the length and diameter of their pellets. Then we read a short article “How Owls Make Pellets,” discussing the key points of the article and the accuracy or inaccuracy of their hypotheses.

• Students view a short clip from “Dirty Jobs: Owl Vomit Collector” which describes how the owl pellets we dissect may have been collected.

• Students put owl pellets in cups of soapy water to soak, making it easier to separate the hair from the bones.

• Students may also view a live owl camera at Starr Ranch (California) to observe a barn owl nest. Pellets and bones may sometimes be observed at the entrance to the nesting cavity.

How do we get owl pellets?

"Dirty Jobs: Owl Vomit Collector“

Live Camera of Barn Owl NestStarr Ranch

• Students strain the pellets, then proceed to separate the hair from the bones, teeth, etc.

• Students use a dichotomous key to identify the skulls of prey animals found in their pellets. They also use reference materials to identify as many bones as possible.

Other Integrating Technology Possibilities

• Discovery Education—video clips from

“The Ultimate Guide: Birds of Prey”

“The Diet and Digestive System of Birds of Prey”

Using The Barn Owl Dichotomous Key

The dichotomous key for skulls from is from a teacher’s guide. A virtual key can be found at http://mypage.direct.ca/m/mgl/BarnOwlPelletDissection/dictkeys.htm.

Vole

mole

• Students use the bones from their pellets to construct a rodent skeleton and classify

additional bones into groups.

• Students post their individual pellet data, then compile class data in order to calculate the barn owl’s most common prey, the average number of prey animals per pellet, and the diversity of species

found in the pellets.

• As they complete their lab reports, students analyze data to make inferences about the niche of the barn owl and its importance to man.

• Students use prey items from their pellet along with additional organisms to create a barn owl food web.

Essential Standards

• 2.1.2—raptor and prey adaptations

• 2.2.3—predation & stability of ecosystems

• 2.2.1—habitat destruction, biological magnification