Lesson Seven: Humans and Marine Ecosystems
This lesson plan adapted from the resource located here.
For this lesson, the two groups of students will learn about the impact of human activity on the environment. Primary impacts are the result of direct use/misuse of the environment (e.g., restoring a reef, dumping directly into the ocean, etc.) Default impacts are the effects of actions/choices made on land that impact the marine ecosystem (e.g., freshwater stream clean-up, agricultural run-off, inland development, etc.) This lesson will focus specifically on primary human impacts on the marine ecosystem through sustainable fishing practices.Download lesson as PDF
- To demonstrate an understanding of the impact that humans have on the marine ecosystems of the world
- Internet-ready computer (class set, or one with a projector) (Note: All information can be pre-downloaded and printed.)
- Monterey Bay Aquarium Seafood Watch cards: National and Regional
- NOAA’s Empty Oceans activity guide
- Student Handout/Chart Paper/Science Journal
- This lesson is best suited for small groups of 4-6 students.
In this lesson, students will learn how pieces of the ocean food web (fish) are being removed faster than they can be replenished and how they can become informed consumers to promote sustainable seafood. Please review the following information with the students, either through handouts or via projector/overhead. Depending on the reading levels of your students you may need to assist and/or read this aloud to them and/or help with definitions to key terms such as “unsustainable” and “bycatch:”
Around the world, fisheries are threatened with collapse due to unsustainable fishing methods and ecosystem destruction. There are a variety of factors affecting the oceans and its inhabitants around the United States. Bycatch, habitat damage, and over-fishing are the primary causes in recent times of the decline in species in the aquatic environment. Bycatch results from fishing methods, such as longlining and bottom trawling, which use very large nets to sweep through the water. Fishermen target a certain species, but the nets and lines catch any marine life in their path. This is a significant problem for threatened and endangered marine species. Turtles, whales, and dolphins often become entangled in nets and lines that hinder their ability to catch food or prevent them from surfacing to breathe. Habitat damage is evident in various ecosystems along the coastal United States. Coastal waters suffer from the constant population growth along the coasts. Bottom trawling drags nets over the seafloor to catch fish, scallops, sea urchins, and crustaceans, but the nets and the rockhopper gear damage coral and places where fish feed and breed. Between 1950 and 1994, commercial fishermen increased their catch by 400% to keep up with the growing demand for seafood. Since 1989, the oceans have been over-fished (fish are caught faster than they can reproduce). However, new boats are set into the waters every year around the world.
- Have the students brainstorm what they know about the fish they eat (e.g., the names of the fish, where and how they were caught) and any other information they know about the fish (e.g., its abundance in the ocean). After the brainstorming session, have each group record the information on a chart and bring the class back together to share ideas.
- Separate the class into groups of four for a jigsaw activity. Have each student visit the Monterey Bay Aquarium Seafood Watch website links in Lesson Plan Assets to learn about the issues surrounding seafood and the fishing gear used to catch seafood. Have each student take notes on one issue. Then, have each student research and take notes on one fishing method. You may want to choose the issue and the fishing method for the students to balance groups. If computer accessibility is a problem, the information can be printed and distributed to the students.
- When the students are finished taking notes on the issues and fishing methods, group the students by method or issue (e.g. the Dredgers) and have them share their information.
- Have students gather back with their original groups of four and share all the information on the fishing methods. Discuss the information using the questions below as a guide. Emphasize that as the demand for seafood has grown and fishing technology has improved, fishermen have improved their skills at catching fish. The United States regulates fishing to try to help fish stocks recover, but many other countries do not. Students should record their responses to these questions in their journals.
- What surprised you the most in your research?
- Which fishing method is the least harmful to the environment? To the non-targeted species (bycatch)? Why?
- Which fishing method is the most harmful to the fish? To the bycatch? Why?
- Why are fishermen using the harmful methods if they cause damage?
- How do these fishing actions affect the sustainability of the resource?
- Wrap up this lesson with the Kure Waste Chase Game. This is an online interactive game by Ocean Adventures where the participant has to identify marine debris; explain multiple effects debris can cause to ecosystems; illustrate general patterns of ocean currents to explain how debris is concentrated in certain areas of the seas; and explore its effect on marine life.
Assess for understanding by evaluating the written responses in the science journal.
Lesson Plan Assets
- This supplemental activity from NOAA focused on how human populations affect marine species populations
- Monterey Bay Aquarium website focused on the many issues related to humans collecting fish from the oceans
- Monterey Bay Aquarium website focused on the many ways humans have invented to efficiently catch fish from our oceans
Project 2061 Benchmarks
- 5D/M1 In any particular environment, the growth and survival of organisms depend on the physical conditions.
- recording data
- Generation of Ideas