1. Explain that this lesson is all about an ecosystem in Florida that exists because of natural springs. Lead a discussion tapping students’ prior knowledge of natural springs. Explain that springs are sources of water that come from the ground and that in the state of Florida there are more than 350 springs.
2. Explain that Florida got its name from a Spanish explorer named Juan Ponce de Leon, who arrived there in the early 1500s, and named it “Florida” for the holiday Pascua Florida, meaning feast of flowers (Easter). According to legend, Ponce de Leon came to Florida in search of the Fountain of Youth-a natural spring that supposedly had rejuvenating powers. FRAME the first video segment by explaining that, although it hasn’t been proven that these springs are fountains of youth, we do have information about how these springs are formed. Let the students know that you are now going to show them a segment with information about Florida’s springs. Provide them with a FOCUS by asking them to describe the steps involved in the formation of the springs.
3. PLAY Video Segment 1, “Florida’s Springs.” (Access the video segments for this lesson at the Video Segments Page.) After playing the segment, FOLLOW UP by asking students to describe the steps involved in the formation of the springs. (1.Rain falls; 2.Water absorbs acids from plants and soil; 3.Acids dissolve limestone bedrock; 4. New cavities open; 5. Tunnels form below; 6. Water releases its minerals underground, drop by drop; 7. Stalactites form.)
4. Optional: To explore the water cycle and its role in the formation of Florida’s springs, explore the “Journey of Water” interactive (http://www.floridasprings.org/anatomy/jow/) with your students. Display the interactive on a screen for all your students to see, click on each of the steps and discuss them with your students.
Learning Activity 1:
1. Explain that scientists have discovered that there is a long, winding maze of rocky tunnels below Florida’s bedrock, now known as the Floridian Aquifer. FRAME the next clip by explaining that the mineral-rich water from these tunnels bubbles upward into springs and supports diverse, unusual wildlife.
2. Ask students to brainstorm what type of life they think lives in and around springs. Record their answers on the board.
3. Explain that the next segment features some of the species that live in and around the springs. Provide students with a FOCUS by asking 1/3 of the class to look for birds, 1/3 to look for mammals and 1/3 to look for fish. Ask the students to observe the following for their assigned group:
- The names of the species featured;
- Why the animals live in or around the springs;
- What types of food the animals eat and how they get their food.
4. PLAY Video Segment 2, “Life in Florida’s Springs.” After playing the segment, FOLLOW UP, by asking students to name the various species featured in their assigned category and describe why they live in the springs, what they eat and how they get their food.
Possible facts to include in the discussion:
o Sardines try to protect themselves from predators, like amberjacks, with their shiny scales, quick moves and by schooling together. Hundreds of thousands of them seek the fresh water baths for warmth.
o Amberjacks prey on sardines. They expel air from their gills to try to contain them.
o Sunfish clean the manatees of the algae growing on their skin. Sunfish are abundant in the springs.
o Mangrove snappers are saltwater fish. The high calcium concentrations in the water give the springs similar properties to salt water. The snappers stay in the warm springs through the end of winter.
o Striped Mullet harvest the algae which grow on fields of eelgrass.
o Manatees are very gentle and migrate every winter to Florida to swim in the warm springs. Here are some other facts presented in the segment:
- For manatees, the springs are the difference between life and death. If the waters cool below 68 degrees Fahrenheit, they can die.
- Manatees sleep a lot during the winter, surfacing to breathe without waking up.
- Sunfish help clean manatees of the algae growing on their skin.
- Manatees are strict vegetarians. They can eat 100 lbs a day and can weigh more than 1 ½ tons. (3000 pounds).
- Manatees are highly endangered and only about 2000 manatees are left in Florida. Boat propellers have killed many manatees.
o Double-crested cormorants live by the springs all year round. They prey on fish, such as sunfish.
o Great blue herons prey on fish, such as sunfish. They are very patient and wait for their prey.
o Eagles prey on fish.
o Osprey prey on fish.
Learning Activity 2:
1. Explain that in any ecosystem there are producers and consumers. The plants in the ecosystem are the producers, since they use light energy from the sun to produce food. Then there are animals, called consumers who cannot produce their own food and eat the producers and/or other consumers. The consumers are divided into three categories:
- Primary consumers are herbivores and only eat plants.
- Secondary consumers are predators, which eat the primary consumers (their prey).
- Tertiary consumers eat the primary and secondary consumers.
Note: Secondary and tertiary consumers can either be carnivores (eating meat) or omnivores (eating meat and plants).
2. Display the “Producer/ Consumer Pyramid” (PDF) or recreate the pyramid on a classroom board to illustrate how producers and consumers are typically represented in an ecosystem. Discuss with your students how, normally, the numbers decrease as you move up from producers through to tertiary consumers. Explain that in most ecosystems there are more prey than predators. As you go up the pyramid from producer to prey to predators, the numbers of animals normally decrease.
3. Explain that we are now going to explore the producers and consumers in the Florida springs ecosystem. Divide the students into groups of 3-5 students. Hand out the “Producer/Consumer Game” to each group. (RTF) (PDF) (Distribute one set of 15 cards and one chart to each group.)
4. Instruct your students to place each card into one of the four boxes on the chart, based on the information that they learned from the video (”tertiary consumers,” “secondary consumers,” “primary consumers” or “producers”). Encourage your students to conduct more research, as needed, to get more information about what the species eat. If students are not sure which category to put a species in, encourage them to choose the category that most closely describes its eating habits. After groups have sorted all their cards onto their charts, ask each group to write the name of each species into its corresponding box in the chart.
5. Lead a discussion with the class about how the students grouped the species and why. The table below provides a suggestion for how to categorize the species, as well as information about some of the food that each species eats:
o striped mullet (eat algae off of eelgrass, dead plants & zooplankton.)
|o amberjacks (eat fish)
o eagles (eat fish)
o double-crested cormorants
o great blue herons (eat fish)
o mangrove snappers (eat fish and crustaceans, such as crab and shrimp)
o osprey (eat fish)
o sunfish (eat algae off of manatees, also eat small insects, snails and other invertebrates)
(eat birds, fish & mammals)
6. Discuss some of the findings from the above activity. (Many of the species are secondary consumers.) Explain to your students that there are actually more predators than prey in the Florida springs ecosystem and that this type of ecosystem is referred to as an “inverted food pyramid.” Explain that this is very unusual and occurs in only a few places in the world. Let your students know that in most ecosystems there are more prey than predators. Ask for a volunteer to define “ecosystem” (a unit of interdependent organisms, sharing the same habitat).
7. Explain that in an ecosystem, in addition to producers and consumers, there are also “decomposers.” Ask for a volunteer to explain the term “decomposer.” (Decomposers are organisms that feed on dead or decaying species. They break down dead plants and animals and release their organic compounds and minerals into the soil. Producers then use these materials, along with energy from the sun, to create food.) Ask students for examples of decomposers (bacteria and fungi). Discuss why decomposers are an important part of the ecosystem. (They help provide organic compounds and mineral that producers need to create food.)
Learning Activity 3:
1. FRAME the next segment by telling students that you are now going to show them a segment about something called “red tide,” which is harmful to manatees. FOCUS the students by asking them to find out what red tide is, how it gets into the springs and how it affects manatees.
2. PLAY Video Segment 3, “Red Tide.” (Access the video segments for this lesson at the Video Segments Page.) FOLLOW UP by asking students to discuss what they learned about red tide.
- Hundreds of millions of gallons of spring water are pumped out each day from Florida’s aquifer to water crops, lawns and golf courses, which are all treated with fertilizers, containing nitrates.
- Much of the used water goes back into the aquifer, along with the nitrates.
- Nitrates cause an outbreak of algae, which produces toxins.
- The toxins create a deadly event called red tide.
- Red tide kills manatees. It killed more than 300 manatees in a few months.
- Red tide could wipe out the entire manatee population.
- The poison of red tide can seep into the aquifer and slowly work its way through miles of underground rivers.
Additional information not in the video: Red tide is a phenomenon (also known as a “harmful algal bloom”) that happens when microscopic algae called Karenia brevis (K. brevis) grow quickly and cause blooms, which give the water a red-brown color. The K. brevis algae create poisonous brevetoxins which can kill marine organisms.
1. Instruct students to work in pairs or alone to gather information about a species that lives in or around the Florida springs. Encourage students to conduct research using books, reference materials and/or online resources. Here are some sites that have good information and photographs about life in the springs:
2. Ask students to complete the “Life in Florida’s Springs Fact Sheet” (RTF) (PDF) with information about their species and to prepare a brief presentation about their findings. As part of the presentation students should show the class an image of their species.
3. Students should give presentations about their species to the class. After the presentations, lead a brief discussion about some of their research findings. Discuss some similarities and differences between the featured species.
4. Optional: Compile all of the fact sheets to create a class book about Florida’s springs.
Extension Activity (Optional):
1. FRAME the video segment, “Life in the Water Supply,” by asking students where they think their drinking water comes from. (Access the video segments for this lesson at the Video Segments Page.) Explain that water that people drink comes from a variety of sources, including rivers, lakes, reservoirs and springs. Let them know that the next segment provides a close-up look at a water supply in Florida. Explain that the segment highlights some things growing in the water supply. FOCUS the students, by asking them to find out what living things are in the water supply and what makes it possible for them to survive there.
2. PLAY Video Segment 4, “Life in the Water Supply.” (Access the video segments for this lesson at the Video Segments Page.) FOLLOW UP by asking students to describe the things living in the water supply. (Answer: Hydroids–small filter-feeding organisms– and mussels.) Ask students what enables these to live in the water supply. (Answer: Bacteria) Lead a discussion with your students about the life in the water supply and how the bacteria support it. During the discussion, point out that in almost every living system, the sun makes it possible for life to exist. In this particular situation, bacteria take the place of sunlight.
Possible topics to discuss:
- In the water supply shown in the segment, there are hydroids and mussels, neither of which is found in springs above. Both are anchored to rock and live on food that drifts by.
- In almost every living system the sun provides fuel for all life, but in the underwater location featured, there is no sunlight. A type of bacteria, which looks like a thin, cloudy substance and lives on a microscopic horizon between fresh and salt water, provides the basis for all life in the cave.
- The bacteria metabolize sulfur from the water and multiply and, in turn, become food for the mussels and hydroids downstream. In the cave, bacteria take the place of sunlight.
3. Optional: If your students do not know where their drinking water comes from, provide them with 15-20 minutes to conduct research to find out. Here are some online resources that can be helpful in this search:
http://www.water-ed.org/watersources/ (for California-specific information)