“The Ecosystem Disrupters: A Middle School
Look at Aquatic Invasive Species in Oregon”
Developed by Thea Hayes, with Gerilyn Howard, for the OSU Extension
Service Sea Grant Program; implemented in the OMSI Watershed and Life
Labs.
Grade Level: 6-8th Grades
Time of Implementation: 45 minutes
Purpose: Students will be able to identify the parts of a food web in a
pacific northwest freshwater aquatic ecosystem, and understand the role of
aquatic invasive species in the disruption of that system.
Benchmarks addressed: Identify and describe factors that influence the
balance and interdependence of populations of organisms in an ecosystem,
Identify populations of organisms within an ecosystem by the function that
they serve, Differentiate between relationships among organisms including
predator-prey, producer-consumer, and parasite-host (cause & effect
relationships in biological and physical systems), Explain the importance of
niche to and organism’s ability to avoid direct competition for resources.
Materials/Supplies Needed:
At OMSI
 Freshwater Salmon Fry Tank
 Freshwater Salmon C--- Tank
 Johnson Creek Tank (w/samples)
 Macro-Invertebrate ID books
 Projector/Microscope
 PNW Wall Map
 6 Stereomicroscopes
 Stream-table
Bring: CLIPBOARDS
Hand Lenses
Colored Yarn
Frog Stickers
Bullfrog tadpoles
Push Pins/sticker
Clipboards (10-20)
Butcher Paper (2)
Pencils
Handouts: Aquatic Ecology Vocabulary, Bullfrog Information, Rusty
Crayfish & Brazilian Elodea handout, Sample Food Web (not aquatic
environment), blank paper
Procedure:
1. Anticipatory set: Students are instructed….”You have 1 minute to find
and name the Ecosystem Disrupter” in the Watershed Lab, or any
classroom. Teacher should have set up various samples or photographs
(laminated?) of native species of animals where students can see them.
Students look at species of plants and animals under microscopes and in
containers around Watershed lab, and follow teachers instructions.
2. Teacher holds up SIGN that reads “I’m a Big, Green Eating
Machine….Who Am I?” (Answer: The ADULT version of the Bullfrog
Tadpoles in the lab.)
3. Teacher makes groups of 3-4, and students are sent to observe Native
and Invasive species in OMSI Life Lab. They sketch general and specific
features of animals and plants. If activity is done in classroom, teacher has
prepared stations with exhibits of different aquatic and aquatic-dependent
species (plants and animals) to observe. An alternative to live exhibits
might be informational stations with photographs and display text
(bulleted, not in report form).
4. Students go back to Watershed Lab and receive Vocabulary Sheets. They
fit organisms into a Wetland /Aquatic Food Web in their group by
identifying what they eat, and what eats them.
5. Discuss in whole group the results of their small group.
6. Post larger BLANK food web on wall, and have students offer
suggestions for filling in.
7. Discuss how invasives can take advantage of an aquatic environment.
8. Identify potential sites for disruption in the Food Web by Bull Frogs or
Nutria or Invasive Aquatic Plants; put FROG STICKERS (or other) on spots
where there is potential for ecosystem disruption.
9. Discuss what might be potential ways to STOP invasives from taking
over a habitat, or to remove them once they are present.
Extension Activity:
Stream Table… Have selected students create an environment that shows
how invasives can take advantage of an aquatic environment. Have them
also show potential areas for reducing the threat of the invasives.
Assessment:
1. Students will turn in their group food web with invasives included.
Their design should include plants (producers), animals (primary and
secondary consumers, omnivores), plankton (zoo & phyto), and decomposers
or detritovores, with connecting strands between them. The drawing
should also include pictures, descriptions, and notes. It should NOT include
a food CHAIN or organisms that do not relate to aquatic environments.
References & Resources:
1)Teacher Resources List: http://www.invasivespecies.org/resources/
2)Teaching Students: http://www.sgnis.org/kids/index/html
3)Invasive Species Info. Node: Http://invasivespecies.nbii.gov
4)On the lookout for Aquatic Invaders: Identification Guide for the Pacific
Northwest, by Scott Wiedemer and Samuel Chan, Oregon Sea Grant,
Oregon State University, Corvallis, OR 2008
5)Food Webs: Interconnecting Food Chains, by Susan Gray, Compass Point
Books, Minneapolis, MN 2008
6)Field Trips by Jim Arnosky, Harper Collins Publishers, NY 2002
7)“The Silent Invasion: Oregon Field Guide,”
www.opb.org/programs/ofg/videos
8)www.statesmanjournal.com/apps/pbcs.dll/article?AID=20070922/VIDEO17/
70922008
9)”Nab the Aquatic Invader,” http://www.sgnis.org/kids/
Useful Vocabulary for Students
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Ecosystems
Habitat
Niche
Food Web
Food Chain
Invasive Species
Riparian
Aquatic
Trophic level
Herbivore
Carnivore
Omnivore
Limiting Factor
Decomposer
Autotrophs
Sun
Algae
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Phytoplankton
Zooplankton
Heterotophs
Detritus
Producer
1st Level Consumer
2nd Level Consumer
3rd Level Consumer
Predator
Prey
Adaptation
Population
Community
Species