Lesson 1: What Exactly is a Coral Reef? - The Ocean · PDF fileLesson 1: What Exactly is a Coral Reef? ... Moorea Coral Reef Long Term Ecological Research ... The algae and coral have

Lesson 1: What Exactly is a Coral Reef? Abstract Students will gain an understanding of the basic components of a coral reef ecosystem, with emphasis on specific abiotic and biotic factors crucial to reef health and trophic level relationships among key organisms. Also included in the lesson is an opportunity for students to learn about traditional, Polynesian culture and the native uses of coral reef resources. This is accomplished through a PowerPoint presentation with corresponding student note-taking guide and several short critical thinking group work opportunities throughout the lesson. Learning Objectives After participating in several group activities and viewing a PowerPoint presentation, students will be able to identify several components of a coral reef habitat and categorize them into abiotic factors, biotic factors, and trophic levels. Students will also be able to hypothesize about possible human uses for coral reef resources. Level Middle school Time Required Two 50-minute class periods California Science Education Standards (Grade 7) Grade 7, Content Standard 3: Evolution--Biological evolution accounts for the diversity of species developed through gradual processes over many generations. As a basis for understanding this concept:

a. Students know both genetic variation and environmental factors are causes of evolution and diversity of organisms. b. Students know the reasoning used by Charles Darwin in reaching his conclusion that natural selection is the mechanism of evolution. e. Students know that extinction of a species occurs when the environment changes and the adaptive characteristics of a species are insufficient for its survival.

Materials Moorea Slide Show (Introduction PowerPoint) Abiotic/biotic factor cards (one set per group of students) Student Worksheets (note-taking guide) Trophic Levels PowerPoint Advance Preparation * Make copies of student worksheets * Copy and cut abiotic/biotic factor cards

Moorea Coral Reef Long Term Ecological Research Program Permission granted for printing and copying for local classroom use without modification Developed by Meghan Saxer as a part of the Research Experience for Teachers program Development and distribution funded by the National Science Foundation Page 1

Teacher Background Teacher Background

Biotic Factors: Trophic Levels in a Coral Reef

2

Biotic Factors: Trophic Levels in a Coral Reef Coral reefs, like the majority of habitats on the planet, derive their energy from the sun. Solar energy is converted into chemical energy by organisms conducting photosynthesis. This chemical energy is then passed on to all other organisms within the system through heterotrophic consumption. To put it simply, plants use sunlight to make sugar, some animals get this sugar by eating the plants, and other animals get this energy by eating the plant grazers. This transfer of energy can be tracked in a trophic level chart, like the one below. Following the chart is a brief description of some of the organisms from each trophic level.

Primary Producers… Photosynthetic organisms like phytoplankton, macro algae, and zooxanthellae found inside coral tissue.

Primary Consumers… Herbivorous organisms like zooplankton, striped surgeonfish, dusky farmerfish, and brushtail tangs.

Secondary Consumers… Carnivorous organisms like trumpet fish and yellowlined goatfish.

Tertiary Consumers… Large carnivores like black tip reef sharks, moray eels, and black jacks.

Primary Producers The organisms within a coral reef system that conduct the initial conversion of solar energy into chemical energy are various algae. Some algae work alone, like the fuzzy, filamentous algae found on rocks and dead coral, or the thorny Turbonaria species. Other, smaller algae have evolved to live within the cells of coral. Symbiotic algae within the coral are collectively called zooxanthellae, or symbiodinium. The algae and coral have a mutualistic relationship, meaning both species benefit from the union. The coral provide algae with a protected environment and some of the compounds needed for photosynthesis. In return, zooxanthellae produce oxygen and supply the coral with important metabolic compounds (like glucose, glycerol, and amino acids). This microscopic, photosynthetic alga is one of the most important primary producers within the coral reef system. Coral itself is part of the animal kingdom. Almost all corals are colonial organisms, meaning that large coral structures are made of hundreds to hundreds of thousands of individual animals. Each individual animal is called a polyp. Polyps have a stomach that opens at one end that is surrounded by a circle of tentacles. The polyp uses these tentacles for defense, to capture small planktonic organisms for food, and to clear away debris.


Corals can be categorized as primary producers because they house photosynthetic zooxanthellae, but they can also be categorized as secondary consumers because they actively prey on zooplankton. Scientists call organisms, like coral, that fit into more than one trophic level mixotrophs. NOTE: to keep the concept of trophic levels simple in this introductory lesson, corals will be considered primary producers since the majority of their energy is derived from the photosynthetic zooxanthellae directly within the polyp. Primary Consumers Primary consumers are the herbivorous organisms that are the first to obtain energy straight from the source: algae making sugars through photosynthesis. Some organisms in this trophic level graze on macro algae, like the filamentous algae that grow on dead coral and rock. Examples of these organisms are brushtail tang, dusky farmer fish, and striped surgeonfish. At a smaller level, microscopic zooplankton that feed on phytoplankton also fit into the primary consumer category. Many organisms in the coral reef habitat use the coral structures as shelter, but coral polyps also provide a tasty snack for some organisms as well. Examples of organisms that consume coral are crown of thorns sea stars, bullethead parrotfish, and ornate butterfly fish. For this lesson, these organisms are considered primary consumers since coral is categorized as a primary producer (due to the zooxanthellae). Secondary ConsumersThe organisms in this trophic level are carnivores that consume algae-eating organisms. Secondary consumers in coral reefs include trumpet fish, honeycomb groupers, and yellowlined goatfish. These predators hunt small herbivorous fishes hiding within the coral. Tertiary Consumers The top-dogs in the coral reef are called tertiary consumers. These organisms eat the organisms that eat the organisms that eat algae. Examples include moray eels and black tip reef sharks. Although these organisms receive most of the spotlight at aquariums and in books, they are completely dependant on all the trophic levels below them. If one of the lower levels fails, all the levels above will be negatively affected as well. If coral die, many parrotfish will starve, so grouper will not have enough to eat, which means less grouper for the sharks to eat. This is a concept that should be stressed during this lesson! Teachers might even want students to compare the interdependency of coral reef organisms with other, more familiar systems (like grains-cows-humans).

Abitoic Factors: Affects on Coral Reef Ecosystem The above explanation of a coral reef trophic system includes information only about the biotic factors (the living organisms) in the habitat. So, how do the abiotic factors fit into this intricate system? Sunlight, Clear Water, and Water Depth: Because of their intimate relationship with zooxanthellae, reef-building corals respond to the environment like plants. Algae need light for


photosynthesis, and light travels best through clear water. For this reason, coral reefs are generally found in water with small amounts of suspended material, meaning not a lot of sand or debris floating around. Energy from the sun also diminishes with water depth—more water to penetrate means less energy from the light. This prevents coral reefs from developing below ~50 meters of water. Dissolved Oxygen and Temperature: Oxygen is an element required for respiration in living organisms. Humans and other land organisms acquire oxygen in a gaseous state from the air, but aquatic organisms obtain oxygen in a dissolved form. There is less oxygen in water than in air, so coral reef organisms have evolved many adaptations for capturing as much oxygen as possible (such as high surface area gills in fish). The amount of dissolved oxygen also decreases as water temperature increases. For this reason, organisms that live in areas with high water temperatures (such as coral reefs) need to have adaptations that allow them to function in low oxygen environments. Of course, as sea temperatures increase due to global climate change, species that do not adapt quickly might begin to disappear. Salinity: The ocean has a higher concentration of salt than the concentration of salt within the bodies of most fishes. Since osmosis dictates a flow of water from high concentration (low salt) to low concentration (high salt), fish within a coral reef tend to lose water from their bodies to the surrounding environment. To compensate for this water loss, the fish have adapted to drink salt water and actively excrete excess salt, usually through the gills or through kidney function. Many invertebrates (like coral) maintain the same amount of salt within their cells as the surrounding ocean. This is a useful adaptation unless the salinity level in the ocean becomes so high that it disrupts protein function within cells, which could lead to death.

Importance of Coral Reefs Traditional Polynesia The most important resource that coral reefs provided for native Polynesians was food. The island peoples captured fish with nets, harpoons, baskets, and other tools. Canoes fixed with outriggers were used as fishing vessels in lagoons. Fish rely on coral for shelter and energy, so no coral means no food for people. The fish could be salted, eaten raw, or prepared in many other ways. An important part of Polynesian culture was to share the fish with all the people that helped in the catch, including not just the people on the ocean but also those who helped prepare the tools. Polynesian cultures also use items from the reef to make traditional ornaments. Shells, coral pieces, fish bones and teeth were used to adorn headdresses, clothing, and jewelry. The reef itself provided the native islanders with shelter from wave action. Often times water outside the barrier reef can be rough, while at the same time the lagoon is relatively calm. This helped control erosion and decrease the amount of damage caused by storms.


Global Perspective Coral reefs have an extremely high amount of biodiversity, more than any other marine habitat. By studying these different organisms, scientists believe they have a chance to find cures for human illnesses, like cancer, arthritis, bacterial infections, etc. This directly affects all humans globally, no matter their relative proximity to a coral reef. Resources Background information for this lab was derived from the following websites: NOAA education http://oceanservice.noaa.gov/education/kits/corals/coral02_zooxanthellae.html Osmoregulation and Excretion http://academics.smcvt.edu/dfacey/animalphysiology/osmoregulation/answers.htm

Hawaiian Fishing Traditions www2.hawaii.edu/~dennisk/texts/introfishing.html


http://oceanservice.noaa.gov/education/kits/corals/coral02_zooxanthellae.html

Instructional Procedure: Lesson 1, Introduction to Coral Reefs

Time Instruction Reasoning 15 min Warm-up: The slideshow of coral reef

habitat, organisms and island scenes (Introduction PowerPoint) is continuously looping as students walk in the door.** If possible, play traditional Tahitian music.

Have students write or draw 5 observations/ideas concerning the slides.

Ask each student to share orally one idea with a partner at their table. Then initiate a class discussion.

This introduction activity allows students to identify with the content they will be exploring more in depth in the rest of the lesson. Students have a chance to make their own personal connections with the content, and to share those connections with others.

Sharing in small groups first allows all voices to be heard (even the shy ones), and the whole group discussion opens up multiple perspectives.

25 min What are coral reefs? Categorization Activity

At each table there are several cards with pictures of coral reef abiotic or biotic factors on the front and the name of that object on the back.

The teacher explains that each of these components is necessary to the health and stability of a coral reef habitat. Students must put the cards into categories of their own choosing and be able to explain why the items belong in those categories.

After students have identified their own categories, the teacher explains the terms abiotic and biotic. Students are now asked to sort the cards into these two groups. These groupings are recorded on the student worksheets.

This activity allows students to begin gaining familiarity with organisms and other components of a coral reef.

When they are asked to group objects themselves (without the teacher dictating the categories) they look more closely at objects and find interesting connections (many that the teacher may not have thought of him/herself!).

After defending their reasoning behind the categories they created, the teacher introduces new scientific terminology (abiotic and biotic). Students then demonstrate their understanding of these vocabulary words by re-grouping their cards.

25 min What are coral reefs? Information Gathering

Now that students have had a chance to familiarize themselves with the key players involved in the ecosystem, the teacher can help them see how everything fits together to make a stable community.

The teacher runs through a second PowerPoint presentation that explains how all of the items from the last activity fit together within the coral reef ecosystem (basically, the teacher outlines reef trophic levels). Abiotic factors that could possibly influence the development of organisms’ adaptations are given particular attention.

The influence of abiotic factors on the development of organism adaptations is one of the state standards students are required to know by the end of 7th grade.


Students record facts about coral reefs on a note-taking guide on the back of their worksheets.

25 min Polynesian Culture: How are humans affected by coral reefs?

Students are told that they have been stranded on an island. Within their table groups, students brainstorm possible ways in which they might benefit from the nearby coral reef.

Ideas are shared briefly in a whole class discussion.

The teacher explains how native peoples on the islands utilize the resources available due to the presence of coral reefs. Students take notes on their worksheets.

Again, when you give students a chance to come up with their own ideas, they feel a greater connection to the scientific material. This activity also encourages students to develop their critical thinking skills.

With the final presentation on how humans really do use the coral reefs, students can compare their own ideas to those of a different culture.

10 min Global Perspective: Why should we, in Carpinteria, care about coral reefs?

Teacher initiates a class discussion based on this question.

Students are more engaged with a subject they feel has an impact on their lives.

English Language Learner Modifications As suggested in the SIOP model of ELL instruction, define a specific language objective for the lesson. Provide appropriate sentence frames in a visible location to aid students in meeting the language objective. Example Objective: After discussing trophic levels, students will be able to make inferences about several new organisms and communicate their ideas verbally with a partner. Example Sentence Frames: “I think that a _____________ is a ________________ because _______________”

farmer fish primary consumer its mouth is small and so it would not be able to catch other fish.

Enhancing Understanding (For Honors/GATE) Students who have a good grasp of the content can be further challenged with these questions… Humans have used coral reef resources and lived in close proximity to coral reefs for centuries. How might human activity have impacted the organisms living in this ecosystem?


Other than the examples given earlier in the lesson, what other abiotic factors might be present in coral reefs? How do these factors affect the organisms living in this habitat? Going Further (extensions for High School) Independent research project with in class presentation. Assign each student a different island that has coral reefs. Provide time in class for internet and library research. Students gather information on human inhabitants, coral reef organisms, and the interactions between the two. Students design their own presentation medium (PowerPoint, display board, 3-D models, etc.) and present their findings to the class. Assessment Formative Assessment Opportunities During the PowerPoint presentation, the teacher can monitor student responses to look for concepts students are struggling with, which then allows the teacher to review the specific content that students need help understanding. Summative Assessment Opportunities The students will each turn in their completed worksheets at the end of the lesson. This provides the teacher with concrete responses for assessing what the students were able to gain from the lesson, and can help pinpoint concepts that might need more attention in subsequent lessons. Critical thinking skills were required for the abiotic factor/adaptation chart and for the wrap-up questions, so specific attention should be paid to those portions of the worksheet.


Name:__________________________________________Date:______________Period:______ Name:__________________________________________Date:______________Period:______

Coral Reefs Coral Reefs Warm-up

9

Warm-up: In the box below, write and/or draw at least 5 observations about the pictures in the slideshow. Playing Cards: Study the cards at your table. What do these things have in common? How are they different? Make categories for your cards and record them below. Write a 1 sentence explanation for each category.


What is a coral reef? What is a coral reef?

A coral reef is a _________________, a place where organisms live. The reef is made up of coral, which are animals related to ___________________ and _________________.

A coral reef is a _________________, a place where organisms live. The reef is made up of coral, which are animals related to ___________________ and _________________.

Individuals are called _________________. Draw one here Individuals are called _________________. Draw one here

Coral colonies build the large ___________________ of the reef as they grow. Coral colonies build the large ___________________ of the reef as they grow.

Coral reefs provide _________________ and ___________ for many organisms, like __________________ and ________________. Coral reefs provide _________________ and ___________ for many organisms, like __________________ and ________________.

How do organisms get energy in a coral reef habitat? How do organisms get energy in a coral reef habitat?

Scientists use a ______________ chart to study the feeding relationships of organisms in a habitat. Scientists use a ______________ chart to study the feeding relationships of organisms in a habitat.

Primary (__________) Producers Make sugar through ___________________

Tertiary (_________) Consumers ________ Carnivores

Secondary (___________) Consumers Carnivores: eat __________

Primary (__________) Consumers Herbivores: eat ___________

_________________ make their own food.

These living organisms are __________ Factors

Another word for “make” is…

________________ must eat others for food.

Another word for “eat” is…

Moorea Coral Reef Long Term Ecological Research Program Permission granted for printing and copying for local classroom use without modification Developed by Meghan Saxer as a part of the Research Experience for Teachers program Development and distribution funded by the National Science Foundation Page 10 10

What are Abiotic Factors in a Coral Reef?

Biotic factors are ______________ parts of a habitat. Name 4 coral reef biotic factors

Abiotic factors are _____________________ parts of a habitat. Organisms must adapt to the abiotic factors in their environment in order to survive.

Brainstorm some of the possible adaptations coral reef organisms might have for each of the following abiotic factors. Use complete sentences!!!

Abiotic Factor

Organism Adaptation

Sunlight

Clear Water

Water Depth

Dissolved Oxygen

Temperature

Salinity


Why are coral reefs important? Why are coral reefs important?

You are stranded on a tropical island with the other people at your table, but you are in luck! There are coral reefs in the lagoon around the island. How might you use some of the coral reef abiotic and biotic factors to help you survive? You may draw diagrams and/or write complete sentences to explain your ideas.


Native Polynesian uses of coral reef resources…

12


Put pic of jewelry, hat, dinner plate, waves crossed out

How might coral reefs help YOU?

Wrap-up

1. Name 2 biotic and 2 abiotic factors you might find in your backyard…

2. Barracuda fish can eat dusky farmerfish and yellow lined goatfish. To which trophic level do barracuda belong?


Name:______________Key_______Name:______________Key____________________________Date:______________Period:___ Coral Reefs _____________________Date:______________Period:___ Coral Reefs

Warm-up

13

Warm-up: In the box below, write and/or draw at least 5 observations about the pictures in the slideshow.

Examples: It looks tropical and warm There are lots of fish.

Playing Cards: Study the cards at your table. What do these things have in common? How are they different? Make categories for your cards and record them below. Write a 1 sentence explanation for each category.

Example:

Fish Not Fish

Brushtail tang Sunlight

Shark Oxygen

All the things in the first group are fish, and the items in the second group are not fish.


What is a coral reef? What is a coral reef?

A coral reef is a ______habitat_____, a place where organisms live. The reef is made up of coral, which are animals related to ____anemones______ and ______jellies_______.

A coral reef is a ______habitat_____, a place where organisms live. The reef is made up of coral, which are animals related to ____anemones______ and ______jellies_______.

Individuals are called _____polyps_______. Draw one here Individuals are called _____polyps_______. Draw one here

Coral colonies build the large ___structures___ of the reef as they grow. Coral colonies build the large ___structures___ of the reef as they grow.

Coral reefs provide ___space_______ and ___food________ for many organisms, like _________sharks_________ and _______eels_________. Coral reefs provide ___space_______ and ___food________ for many organisms, like _________sharks_________ and _______eels_________.

How do organisms get energy in a coral reef habitat? How do organisms get energy in a coral reef habitat?

Another word for “make” is… produce

___autotrophs_____ make their own food.

Another word for “eat” is… consume

__heterotrophs_ must eat others for food.

Scientists use a ____trophic__________ chart to study the feeding relationships of organisms in a habitat. Scientists use a ____trophic__________ chart to study the feeding relationships of organisms in a habitat.

14

Primary (_____first_____) Producers ______photosynthesis_______

Zooxanthallae, turbinaria Make sugar through

Tertiary (__third___) Consumers ___Big____ Carnivores sharks, morays

Secondary Carnivores: eat

(__second___) Consumers ____meat_____

Yellowlined goatfish

Eat

Primary Herbivores: eat

(___first_______) Consumers ___algae____

Dusky farmerfish

These living organisms are ___biotic___ Factors Eat

Eat


What are Abiotic Factors in a Coral Reef?

Biotic factors are ____living__________ parts of a habitat. Name 4 coral reef biotic factors sharks, brushtail tang, coral, hermit crabs

Abiotic factors are ____non-living_________________ parts of a habitat. Organisms must adapt to the abiotic factors in their environment in order to survive.

Brainstorm some of the possible adaptations coral reef organisms might have for each of the following abiotic factors. Use complete sentences!!! Answers will vary

Abiotic Factor

Organism Adaptation

Sunlight coral Take up lots of space to get maximum surface area for photosynthesis

Clear Water

Water Depth

Dissolved Oxygen

Temperature

Salinity


Why are coral reefs important? Why are coral reefs important?



We could make a net out of palm leaves and catch fish for dinner.


16


The students could draw pictures of jewelry, hats, dinner plate (food), waves crossed out (less destruction)

How might coral reefs help YOU?

The biodiversity of the reef means there are more species to discover. One of these could be a cure for cancer!

Wrap-up

3. Name 2 biotic and 2 abiotic factors you might find in your backyard…

Dog, tree, rocks, hose 4. Barracuda fish can eat dusky farmerfish and yellow lined goatfish. To which trophic level do barracuda belong? Tertiary consumers


Biotic Factor Cards: Primary Producers


Biotic Factor Cards: Primary Consumers


Biotic Factor Cards: Secondary Consumers


Biotic Factor Cards: Tertiary Consumers


Abiotic Factor Cards Abiotic Factor Cards

Dissolved Oxygen

Temperature

Clear Water


Abiotic Factor Cards Abiotic Factor Cards

Salinity

Sunlight

Water Depth


Documents

Lesson 1: What Exactly is a Coral Reef? - The Ocean · PDF fileLesson 1: What Exactly is a Coral Reef? ... Moorea Coral Reef Long Term Ecological Research ... The algae and coral have