Sequence | Background | Objectives | Materials | Activity | Extensions | Evaluations

TOPIC-TITLE Marine & Aquatic Resources Activities - Exotics in the Local Food Chain AUTHOR Neil Boettcher GRADE SUITABILITY Middle School SCOPE Life Sciences Environmental Science

Sequence Before this lesson students will have studied the water flow patterns of local watersheds, and the students will also have viewed videos focusing on local flora and fauna. < < go top

Background Summary The introduction of exotic species has had a dramatic effect on the native fish populations in many marine and aquatic environments, including the Great Lakes. The introduction of organic and inorganic substances, such as PCBs and DDT, has affected the reproductive processes of fish populations. The rise and fall of the fish populations have had dramatic effects on animal and bird populations, as well as an economic impact on the humans who depend on these resources for their incomes and recreational enjoyment. < < go top Objectives Students will be able to do the following: Understand the role of the food chain. Identify many of the native species in their area. Understand the predator/prey relationship and its effects on local fish populations. Identify exotic species and understand their relationship to native fish populations in their area. < < go top Materials Scissors Colored pencils, crayons, and markers Drawing (construction) paper String Ruler Video equipment < < go top Activity Note: A list of species from recent sampling nets by a local natural resources conservation agency such as the Department of Natural Resources may be helpful for this activity. Begin with a fish parts matching game, using anatomical parts from drawings of native species. Students will assemble their fish and then proceed to draw and color them for display. Using available resources, students will compile brief "biographies" on their fish for a presentation to the class. Each presentation will include habitat, size, preferred food, reproduction, and diagnostic characteristics. Students will construct a food web for their fish and participate in "role-play" based on their food webs. Students will research if exotic species have been introduced in their area. A discussion and "role-play" will then add the exotic species to the food web. Students will analyze the effects of exotics found in their area on the native populations. Students will develop predictions regarding the future of the local ecosystem with respect to overfishing or other environmental concerns. < < go top Possible Extension Math students could calculate the ppm of toxic chemicals in fish species based on the bio-magnification principle. Students could research possible aquaculture careers. Students could examine industries that rely on local watersheds for cooling, water dilution, or manufacturing. A field trip could be arranged to one of these industries for observations of its effects. Prepare a presentation of your findings. Are these industries harmful to fish, water, birds, humans, or the environment? Students could research the affects of exotic species on other ecosystems (such as zebra mussels in the Great Lakes). Students could compare and contrast the effects. < < go top Teacher Evaluation Grade students for participation in the activities. Use a short essay exam, including questions such as these: Can we stop the parade of exotics into the environment? How do toxins in fish affect various bird populations? How will the United States fisheries change in the future? Display the completed fish models. < < go top