1 / 24

Lab 10 Food Web

Lab 10 Food Web. BY-102 Zach Nolen. What is a food chain?. The order of who eats who Examples: Seeds → Grasshopper → Mouse → Owl. What about a Food Web?. Interconnection of several food chains to form more complex relationships. Trophic Levels.

paiva
Download Presentation

Lab 10 Food Web

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Lab 10Food Web BY-102 Zach Nolen

  2. What is a food chain? • The order of who eats who • Examples: • Seeds → Grasshopper → Mouse → Owl

  3. What about a Food Web? • Interconnection of several food chains to form more complex relationships.

  4. Trophic Levels Are based on the position that an organism holds in a food chain.

  5. Food Sources

  6. Owl video

  7. Try to answer the following questions. • Where do they live? • How long do they live? • Where do they hunt? • How many owlets do they have? • When do the owlets hatch? • Why are owls such good hunters? • How are owl pellets formed? • Describe the digestive process of the barn owl. • Number and name(s) of stomach(s), etc… • What dangers do barn owls face?

  8. Review questions

  9. Where do they live? • Tyto alba (Barn Owl) • Habitat • Barns • Silos • Hollowed trees

  10. How long do they live? • In the wild: 1-5 years • Protected environments: 20-25 years

  11. How many owlets do they have? • Average clutch size is 4-7 owlets

  12. When do the owlets hatch? • Eggs are laid 2 days apart and hatch in 2 day intervals

  13. Describe the digestive process of the barn owl. • 2 stomachs • Glandular stomach – secretes digestive enzymes to separate the fleshy portions of prey from the bones, hair, and fur. • Muscular stomach – further breaks down fleshy portions of food.

  14. How are owl pellets formed? • Prey is swallowed whole • Reached gladular stomach. Fleshy portion passes to next stomach. • Hair, feathers, and bones remain in glandular stomach.

  15. How are owl pellets formed? • Fleshy portion is further broken down by muscular stomach and nutrients are absorbed. • Waste matter (uric acid) is excreted. • Hair, feathers, and bones are compacted into a bolus in the glandular stomach and regurgitate.

  16. What dangers do barn owls face? • Harsh weather conditions • Busy railways and motorways • Loss of habitat • Drowning in water troughs • Loss of suitable nesting sites

  17. Potential Prey of Tyto alba Shrew Vole Mouse Bird Rat Insect

  18. What is a dichotomous key? • A tool that allows easy identification of items. • Key provides 2 choices at a time • Think of these as a “choose your own story” where your choices affect the final outcome.

  19. Dissecting Owl Pellets • Open foil wrapping • Gently find a place to start your dissection • Use tweezers, probes, and your hands to separate the bones from the hair and feathers.

  20. Dissecting Owl Pellets • After you have found as much as possible, use the dichotomous key on page 111 to identify any skulls that you found. • If you did not find any skulls, use the key on page 112 to match the bones that you found.

  21. Class findings

  22. Review Questions • What is a food chain? • What is the difference between a food chain and a food web? • What is the scientific name for the barn owl? • How are owl pellets formed?

  23. Before You Leave Lab • Clean up your work station.

  24. Before Next Lab • Complete all sections of lab manual for final lab manual check • Complete Study guide 3 (Optional) • Study for test

More Related