Cascades to Coast GK12 Curriculum
Aquatic Ecology Fellow: Nicole Alfafara (Environmental Science and Management)
Teacher: Brie Bui-Hirschberg (Dexter McCarty Middle School) Unit Learning Objectives: Introduce students to common lake ecology concepts and issues.
• Food Chain
• Food Web
• Harmful Algal Blooms
• Biomagnification
• Biomanipulation
Concept Overview and Resources The information below is meant to provide a brief overview of the concepts touched on in the following lesson plans and provide additional resources for educators.
• Food Chain: diagram describing the transfer of energy between organisms within an ecosystem. Food chains show how different organisms are related to each other based on the food they eat.
• Food Web: network of connected food chains in an ecosystem. o References for additional information:
http://www.miseagrant.umich.edu/lessons/lessons/by-broad-concept/life-science/food-chains-and-webs/
http://idahoptv.org/sciencetrek/topics/food_chain/facts.cfm http://w3.marietta.edu/~biol/102/ecosystem.html
• Harmful Algal Blooms: accumulation of algae that can produce toxins in aquatic environments.
Image Credit: http://water.usgs.gov/edu/photo-‐gallery/large/eutrophic-‐lake.jpg
o References for additional information: https://www.epa.gov/nutrientpollution/harmful-algal-blooms http://blooms.uwcfl.org/what-are-habs/ http://www.cdc.gov/nceh/hsb/hab/
• Biomagnification: when a substance/contaminate becomes more concentrated or increases within an
organism as you move up the food chain.
Image Credit: http://biologyasifitmattered.blogspot.com/2011/08/ecology.html
o References for additional information: http://education.nationalgeographic.org/media/biomagnification/ https://www.youtube.com/watch?v=RP9hmlRqbxs http://toxics.usgs.gov/definitions/biomagnification.html
• Biomanipulation: changing the biological community to achieve desirable change in the environment.
Image Credit: http://www.lan.krasu.ru/rec/science/t4_e.html
• Trophic Cascades: when predators in a food web reduce their prey population and that impacts further
down the food chain are observed.
o References for additional information: http://lakes.chebucto.org/biomanip.html http://www.britannica.com/science/trophic-cascade http://www.missionwolf.org/page/trophic-cascade/ http://www.ecology.com/2014/03/05/trophic-cascade-wolves-change-rivers/ https://www.youtube.com/watch?v=cz5tFQVYFBs
Lesson 1: Toxin Biomagnification up the Food Chain (Outdoor Activity)
Learning Objective: Introduce students to the concept of biomagnification while enhancing existing knowledge of trophic levels in a food chain.
Overview: Students learn about the food web and trophic levels by experiencing/acting out different scenarios. of how their feeding decisions will impact other trophic levels and their survival in the environment. Target Grade: 6-8th Science Class
6th , 7th , and 8th Grade State Standards: • 6-8.RST.3 Follow precisely a multistep procedure when carrying out experiments, taking measurements,
or performing technical tasks. • 6-8.RST.4 Determine the meaning of symbols, key terms, and other domain-specific words and phrases
as they are used in a specific scientific or technical context relevant to grades 6-8 texts and topics. • 6-8.RST.9 Compare and contrast the information gained from experiments, simulations, video, or
multimedia sources with that gained from reading a text on the same topic. • 6-8.WST.2 Write informative/explanatory texts, including the narration of historical events, scientific
procedures, experiments, or technical processes. (See last page for complete steps in writing informative/explanatory texts.)
• 6-8.WST.9 Draw evidence from informational texts to support analysis, reflection, and research. Duration: 50 minutes
Materials: • Small paper bags • Poker chips: • 70% White (~ 100 chips) • 30% Red (~ 40 red chips) • Stopwatch • Lake Organism Cards
Pre-Activity Topic Introduction: 1. Present a common Lake Food Web to the students.
a. Consider having students do research gathering basic information (physical description, habitat,
fun facts) on the trophic groups in this activity:
Top Predator Human Fisherman Tertiary Consumer Lake Trout Secondary Consumer Bluegill Primary Consumer Zooplankton Producer Algae
Then you could have the students collect information that is already provided on the “Lake Organism Cards”.
2. Introduce the topic of toxins and pollutants in the environment. a. Ask students: “How can toxins impact an ecosystem?” b. Example: Story of DDT Biomagnification: (An example of how biomagnification of a toxic
substance impacts an ecosystem) DDT is metabolized and excreted much more slowly than the nutrients that are passed from one trophic level to the next. So DDT accumulates in the bodies (especially in fat). Spraying a marsh to control mosquitoes will cause trace amounts of DDT to accumulate in the cells of microscopic aquatic organisms, the plankton, in the marsh. In feeding on the plankton, filter-feeders, like clams and some fish, harvest DDT as well as food. (Concentrations of DDT 10 times greater than those in the plankton have been measured in clams.) The process of concentration goes right on up the food chain from one trophic level to the next. Gulls, which feed on clams, may accumulate DDT to 40 or more times the concentration in their prey. This represents a 400-fold increase in concentration along the length of this short food chain. There is abundant evidence that some carnivores at the ends of longer food chains (e.g. ospreys, pelicans, falcons, and eagles) suffered serious declines in fecundity and hence in population size because of this phenomenon in the years before use of DDT was banned (1972) in the United States.
Reference: http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/D/DDTandTrophicLevels.html
Activity Preparation/Set-up: • Scope out a clear, level game area. Think about how you will designate boundaries. Consider potential
alternatives for bad weather. • Accessibility: If one of your students has limited mobility or sight, plan for how you will get him or her
involved. (For example, s/he could play the top predator, be the time-keeper, record numbers or calculate percentage eaten, etc.).
• Without the students watching, randomly distribute the poker chips in a defined grassy area.
Activity Plan/Procedure: 1. Assigning Lake Organism Roles & Distribute Materials:
o Divide class into five trophic groups. If you have 33 students, assign roles as follows: 1 Human Fisherman, 3 Lake Trout, 9 Bluegills, and 20 Zooplankton.
Trophic groups for this activity:
Top Predator Human Fisherman Tertiary Consumer Lake Trout Secondary Consumer Bluegill Primary Consumer Zooplankton Producer Algae
o Have the students in each role agree upon a species-specific form of movement (i.e. students
assigned lake trout motion their hand as fins). o Give each student a paper bag. Explain that the playing area is PSU Lake, the habitat where they
live. The poker chips represent blue-green algae, which has become abundant.
o Distribute the appropriate “Organism Card” to each student and explain that each “animal” is being given specific directions as to how they should respond to this algae bloom when directed to do so.
2. Direct Feeding of Organisms: Guide students through the following series of events where they will follow the directions provided on their “Organism Card”:
o Step 1 – The Zooplankton: Tell the Zooplankton that they will have 30-60 seconds (depending on the number of students involved and the size of the area) to “graze.” They should move around the area, feeding on the algae (i.e., collecting poker chips and putting them in their food bags). At the end of the timed period, the Zooplankton should remain where they are in the area, but stop collecting poker chips. (Note: In our food chain, zooplankton are the only organisms that can eat the algae.)
o Step 2 – The Bluegills: Tell the Bluegills to enter the feeding area and do what is indicated on their “Organism Card.” Explain to the class that in this simulation, predators “eat” their prey by tagging their prey’s elbow. Once an organism is “eaten,” it relinquishes its food bag to its predator and sits down in the feeding area. During this time, the living zooplankton can continue to graze on the algae.
o Step 3 – The Lake Trout: Once the fish accomplish what they are guided to do by their “Organism Cards,” tell the Lake Trout to enter the feeding area and accomplish what is on their “Organism Card.”
o Step 4 – The Human fisherman: Once the Lake Trout complete their tasks, allow the humans to enter the feeding area and accomplish what is indicated on the human “Organism Card.”
3. Share Organisms Card Directions and Reveal Harmful Algal Bloom Development: o Once the Human Fisherman has eaten, review what occurred by having students share what was
written on their “Organism Card” starting with the Zooplankton and ending with the Human Fisherman.
o At this time, inform the students that some of the algae that they ate were toxic! Some algae such as blue-green algae produce toxins called cyanotoxins.
4. Calculating Toxicity: Have the students go through their food bags and sort their food. Have them count the total number of poker chips they collected and the number of red chips they collected. They should then calculate the amount of toxic algae they ate as a percent of their total consumption.
100 x [# of red chips] / [total # of chips consumed] 5. Announce Survivor Requirements:
o Uneaten Zooplankton that “ate”/consumed ANY red chips = are now dead. o Uneaten Bluegills that “consumed” 20% or more red poker chip algae = are now dead. o Uneaten Lake Trout that consumed between 20-30% red poker chip algae = are now sick. o Uneaten Lake Trout that consumed over 30% red chips = are now dead. o If the Human Fisherman consumed between 20-30% red poker chip algae = he/she is now sick. o If the Human Fisherman consumed over 30% red chips, he/she is now dead.
Clean up: Make sure that all of the poker chips have been collected. Consider using a police line to scour the area.
Class Discussion Discuss the conclusions that can be made from this activity. As students describe their observations, encourage them to use terminology related to food webs and trophic levels.
Assessment Questions to Facilitate Class Discussion: • What is biomagnification? • What would happen to the rest of the food chain if there were barely any zooplankton? Now assume
other scenarios of the other trophic levels lacking in numbers and analyze how it would affect the food web.
• Does this food chain affect humans or not? Why or why not?
• What does the word toxic mean? • How do toxins affect the food web? **Alternative: Create student handout to have student’s answer these questions.
Additional Questions to Facilitate Class Discussion: • “Eating lower on the food chain” or “buying and eating locally” – What do these phrases mean? • Why should we consider their messages when making personal lifestyle decisions? [Mention ecological
and monetary costs of production, processing, packaging, transportation, shelf-life, etc.] • What are some things that middle school students can do? • How can a toxic substance that is accumulating in the tissues of organisms in one ecosystem move into a
completely different ecosystem? Give an example. [For ideas, see article: “Mercury in river moves into terrestrial food chain through spiders fed to baby birds / https://www.sciencedaily.com/releases/2008/04/080417175221.htm.”
References: This activity was modified from:
• https://www.epa.gov/sites/production/files/documents/biomagnificationroleplayandstencilactivity.pdf • https://www.bigelow.org/edhab/tracing_toxins.html • http://www.fofweb.com/Electronic_Images/Onfiles/SEOFv2-48.pdf • https://sharkresearch.rsmas.miami.edu/assets/pdfs/learning-tools/high-
school/MODULE%204%20Marine%20Issues%20-%20SECTION%203%20%20Pollution,%20Water%20Quality%20and%20Bioaccumulation.pdf
Lake Organism Cards: Note:
• You might have to adjust the consumption directions based on your class size. • You can have students research information on the lake organisms prior to completing this activity.
Daphnia
Scientific Name: Daphnia magna
Daphnia are planktonic crustaceans or zooplankton with translucent bodies, compound eyes and antennae. • Size: 0.2 -‐5 mm in length. • Habitat: freshwater lakes, ponds, streams and rivers • Diet: algae, protist and bacteria • Predators: small fish, tadpoles and aquatic insects. • Fun Fact: commonly called water fleas because of their jerky movement and swimming style. Image Credit: http://www.geochembio.com/biology/organisms/daphnia/
Daphnia
Activity Directions: Please graze upon the “Blue-Green Algae”/poker chips by picking them up and placing them into your bag until your teacher tells you to stop.
Blue-Green Algae
Scientific Name: Cyanobacteria
Blue-‐green algae refers to a group of bacteria called Cyanobacteria. • Size: 0.5-‐1 μm to 40 μm in diameter • Habitat: freshwater lakes, ponds, streams, rivers and oceans • Diet: Cyanobacteria contain chlorophyll and other pigments that are used for photosynthesis. • Predators: Zooplankton such as Daphnia. • Fun Fact: When cyanobacteria enter a period of rapid cell division they form “blooms”. These blooms produce
toxins and be can be dangerous to other organisms. Image Credit: https://www.fossweb.com/delegate/ssi-‐foss-‐ucm/Contribution%20Folders/FOSS/multimedia_ms_1E/PopulationsandEcosystems/organismdatabase/orgpages/1171_0.html
Blue-Green Algae
Activity Directions: Represented by Poker Chips.
Lake Trout
Scientific Name: Salvelinus namaycush
Lake trout have small cream or yellow, irregular shaped spots on a gray-‐to-‐dark green body with wavy lines along the dorsal side and deeply forked tail.
• Size: 24-‐36 inches on average • Habitat: • Diet: Zooplankton, insect larvae, clams, snails, leeches, other fish, and young birds. • Predators: Human Fisherman • Fun Fact: are avidly sought after by both commercial and sport fisherman for food and sport.
Image Credit: http://www.fishinfo.com/fishing-‐information/article_51.shtml
Lake Trout
Activity Directions: Please eat 2 Blue Gills by touching their elbow and collecting all the bags they have.
Blue Gill
Scientific Name: Lepomis macrochirus
Blue Gills are fish with two dorsal fins with spinous and soft-‐rayed portions united, small mouth, long pointed pectoral fins, faint black spot on soft-‐rayed part of dorsal fin.
• Size: species averages only 5 -‐7 inches • Habitat: midsize streams, ponds, lakes and rivers. • Diet: Young fry eat algae and zooplankton and later add small fish, aquatic insects and plant matter. • Predators: Larger fish, birds, and fisherman • Fun Fact: remain active all winter providing good winter sport.
Image Credit: http://www.fishinfo.com/fishing-‐information/article_51.shtml
Blue Gill
Activity Directions: Please eat 2 Daphnia by touching their elbow and collecting all the bags they have.
Fisherman
Scientific Name: Homo Sapiens
Characteristics: • Humans have a complicated and most sophisticated brain like no other species on this planet. • Some humans eat plants but other humans eat plants and animals. Most fishmerman like to eat fish
that they catch.
Fisherman
Activity Directions: Please eat 1 Lake Trout by touching their elbow and collecting all the bags they have.
Lesson 2: Biomanipulation and Trophic Cascades in Aquatic Ecosystems
Learning Objective: Introduce students to the concept of biomanipulation and Trophic Cascades to demonstrate the complex relationship between organisms and the aquatic ecosystem. To understand the key concepts, such as biomanipualtion and trophic cascade, we have to understand the food web and how the population of one trophic group can impact other trophic groups.
Overview: Students learn about biomanipulation and trophic cascades and how they can impact the whole food web in a lake. Target Grade: 6-8th Science Class
6th , 7th , and 8th Grade State Standards: • 6-8.RST.3 Follow precisely a multistep procedure when carrying out experiments, taking
measurements, or performing technical tasks. • 6-8.RST.4 Determine the meaning of symbols, key terms, and other domain-specific words and phrases
as they are used in a specific scientific or technical context relevant to grades 6-8 texts and topics. • 6-8.RST.9 Compare and contrast the information gained from experiments, simulations, video, or
multimedia sources with that gained from reading a text on the same topic. • 6-8.WST.2 Write informative/explanatory texts, including the narration of historical events, scientific
procedures, experiments, or technical processes. (See last page for complete steps in writing informative/explanatory texts.)
• 6-8.WST.9 Draw evidence from informational texts to support analysis, reflection, and research. Duration: 30 minutes
Materials: • Plastic or small paper bags • 1 lb of M&M’s (10 green colored M&M’s, 15 yellow colored M&M’s, and 5 blue colored M&M’s • Stopwatch • Pictures of organisms • Organism Cards
Pre-Activity Topic Introduction: 1. Present a common Lake Food Web to the students.
2. Introduce the following topics: trophic groups, trophic cascades and biomanipulation
a. Food Web b. Trophic Group c. Trophic Cascades d. Biomanipulation
Trophic groups for this activity:
Top Predator Lake Trout Secondary Consumer Bluegill Primary Consumer Zooplankton Producer Algae
Activity Preparation/Set-up: • Make Bags of M&M’s. Each bag should have 10 green colored M&M’s, 15yellow colored M&M’s, and
5 blue colored M&M’s. Be sure to make enough bags so students can work in groups of 2. • Accessibility: If one of your students has limited mobility or sight, plan for how you will get him or her
involved. (For example, s/he could play the top predator, be the time-keeper, record numbers or calculate percentage eaten, etc.).
• Without the students watching, randomly distribute the poker chips in a defined grassy area.
Activity Procedure: 1. Distribute Materials:
o Hand out bags and have students separate the M&M’s into groups based on color. o Each group/color of M&M’s represents a different trophic group/organism.
o Green = Algae o Yellow = Zooplankton o Blue = Blue gill.
2. Set up Lake PSU: o Lake PSU has 5 blue gills, 15 zooplankton and 10 algae colonies. Have students assemble the
biotic community of Lake PSU by placing the appropriate color and number of M&M’s in a pile. 3. Propose Management Scenario:
o The Fisheries and Wildlife Department decide to stock Lake PSU with Lake Trout. They place 3 Lake Trout into Lake PSU.
4. Brainstorming & Hypotheses: o Have each group hypothesize what will happen to the aquatic life (Blue gill, Zooplankton and
Algae) in Lake PSU after the introduction of the 3 Lake Trout. Encourage students to be as detailed as possible and write down what might happen to the food chain if one of the trophic groups’ population increases or decreases.
o EX: If Lake PSU is stocked with 3 Lake Trout then ___ because ___. 5. Class Discussion Presenting Hypotheses:
o Have a class discussion for about 15 min regarding this to get all the ideas from the kids and write them on the board. Then introduce and explain the word biomanipulation and trophic cascades to the whole class.
Assessment Questions to Facilitate Class Discussion: • What is biomanipulation? • Describe the concept of a Trophic Cascade. • Does the increase or decrease in any of these trophic groups impact the other animals in
the food web? If so how? (You can be general) • **Alternative: Create student handout to have student’s answer these questions.
Additional Question to Facilitate Class Discussion: • Do you think that biomanipulation is a good environmental management method to
decrease algae?