Meet the underwater characters that make a living cycling nutrients through the watershed. Learn how the physical, chemical, and biological systems within watersheds work together to create a continuum of resilient, interconnected ecosystems. Watch the food chains spiral nutrients in and out of the river basin in vast web of interactions. Click for a PDF of the video transcript. This website is part of the Surface Water series.
Pre-viewing Question
- What do you think happens to all the nutrients that enter the watershed through the excrement of aquatic organisms?
Discussion Questions
- Use your imagination to list ten types of substances for microbes to colonize in the headwaters, mid-sized streams, and rivers.
- What would happen to this food web if collector organisms like Hydropsychae and Maccaffertium were absent?
- How do nutrients travel upstream from rivers to headwaters?
- How do nutrients spiral up and out of the watershed permanently?
Post-viewing Question
- Which stream would you prefer your city's water treatment plant pull your drinking water from: one with or without a food web of macroinvertebrates? Why?
Extension Activity
- Watch How Wolves Change Rivers and discuss what might happen to the food web if the aquatic predators like Eccoptera, Rhyacophila and Aeshna were absent from the watershed.
Links to Learn More
- Mayfly Eggs Hatching Minutes after Being Laid, Stroud Water Research Center
This silent three-minute video beautifully illustrates the ephemeral life of mayflies. - American Pheasant Tail Nymph, Tightline Productions
This six-minute amateur video shows how to tie a fly for fly fishing. - Yellowstone Ecosystem Needs Wolves and Willows, Elk and Beavers, NSF
Read how wolves, willows, elk and beavers are all crucial, interconnected pieces of the ecosystem in Yellowstone National Park.
Next Generation Science Standards
- Performance Expectation: Develop a model to describe the cycling of matter and flow of energy among living and nonliving parts of an ecosystem. HS-LS2-3
- Disciplinary Core Idea: Ecosystems are dynamic in nature; their characteristics can vary over time. Disruptions to any physical or biological component of an ecosystem can lead to shifts in all its populations. LS2.C
- Crosscutting Concept: Energy and matter
- Engineering Practice: Developing and using models