Finding Answers in the Marine Ecosystem


Lesson Plan: Fish Oil, Really?

Lesson Plan Standards

3.1.1 3.5.1 3.5.2 3.5.3 3.5.4 3.6.2


Students will gain a better understanding of the marine food chain and how fish are adapted for consuming algae and other organisms.  This, in turn, will provide a better context for the origin of omega-3 fatty acid production in the marine ecosystem.  Students will be able to make connections to the marine food chain and it's significant role in the health of our oceans and our society.  



Students will be introduced to a common producer in the marine environment by examining a live algae sample under the microscope.

Students will gain a better understanding of the importance of Menhaden in Chesapeake Bay and it's connection to consumer science.

Students will make connections between the value of the menhaden fishery and fish oil products produced by different manufacturing processes.

Lesson Materials

Microscope, compound and dissecting

Algae (live green species)

Fish gill samples and/or photos of fish gills to examine

Fish Oil, Really? Content Primer section on Sustainability


  1. Introduce the following key terms that will be important for small group discussion during this activity; producersconsumers, food chain, food web, marine ecosystem, gills, gill rakers, and sustainability.
  2. Revisit the observations about the Fish Oil supplements and again ask,"Where does Fish Oil come from"?
  3. Students (individual or in groups) will examine an algae sample with a microscope to make observations about a producer similar to those found in the marine food chain / web.
  4. Students (individual or in groups) will examine fish gill samples with a dissecting microscope.  The key features to identify are: Gill Arch, Gill Filament, and Gill Raker (see link for basic anatomy).  Fish gill photos should also be examined so students can understand the form and function of the gill in different fish (see links in Reference section).  These observations will help students better understand the purpose of a fish gill and the specificity of menhaden gill structure and function.
  5. After these observations are complete students will form small groups again to discuss the form and function of various fish gills and how it relates to what fish consume.  Specifically, menhaden should be compared to other fish.
  6. After this discussion is complete students should share ideas with other groups to form consensus.
  7. To make connections to the marine food chain and the role menhaden play in Chesapeake Bay students will read the section on Sustainability from the Fish Oil, Really primer and then follow-up with discussion items below.

Formative Assessment – ​​Where does fish oil come from and what are the impacts of choosing different types of fish oil supplements?  Group discussion should include the key terms introduced and address the following questions:

What is the connection between the algae-base supplement, human population, and fish populations? 

What is the connection between the fish capsule, human population and fish population? 

Are the same nutrients gained from each tablet? 

Develop two food chains that represent sustainable and unsustainable fish oil production using the following:

Marine Ecosystem, Algae, Menhaden, Human, Factory Processing, Purse seining, Algae Fermentation


For more information download the Content Primer

Basic Anatomy Description

Gills of the Snow Trout

Anatomy Image of Gills

Anatomy Image of Gills

North Pacific Native Salmon

Maryland State Standards

The student will be able to describe the unique characteristics of chemical substances and macromolecules utilized by living systems.
The student will analyze the relationships between biotic diversity and abiotic factors in environments and the resulting influence on ecosystems.
The student will analyze the interrelationships and interdependencies among different organisms and explain how these relationships contribute to the stability of the ecosystem.
The student will investigate how natural and man-made changes in environmental conditions will affect individual organisms and the dynamics of populations.
The student will illustrate how all organisms are part of and depend on two major global food webs that are positively or negatively influenced by human activity and technology.
The student will investigate a biological issue and be able to defend their position on topics such as animal rights, drug and alcohol abuse, viral diseases (e.g., AIDS), genetic engineering, bioethics, biodiversity, population growth, global sustainability, or origin of life. (NTB)

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