Name: Date:
Student Exploration: Coral Reefs 1 – Abiotic Factors
Vocabulary: consumer, coral, coral bleaching, coral reef, filter feeder, food chain, food web,
grazer, nutrients, ocean acidification, pH, plankton, predator, producer, sediment, zooxanthellae
Prior Knowledge Questions (Do these BEFORE
using the Gizmo.)
1. Look at the graph to the right. What does it show?
Percentage of coral cover in Caribbean Reefs. It
shows a decline over time.
2. Why do you think corals have declined since 1977? People are killing and selling them.
Gizmo Warm-up
Coral reefs are some of the most diverse habitats on
Earth, home to over a quarter of all marine species. The
Coral Reefs Gizmo™ provides a simplified model of
interactions among 10 key species in Caribbean reefs. In
the Coral Reefs 1 exploration, you will focus on the effects
of environmental factors on Caribbean reefs.
1. Click Advance year 10 times. Look carefully at the composition of the reef over time. Do
you see any major changes? The reef stayed consistent.
2. Select the DATA tab. Check that Staghorn coral, Star coral, Sponges, and Algae are
selected. Populations are given as a percentage of normal populations.
What do you notice about these populations? Sponges poulation goes up while the others don't.
3. On the right side of the Gizmo, select the SUMMARY tab. In a healthy reef, what are the
values for Nutrient load, Water clarity, Coral cover, and the total number of fish species?
Nutrient load: 4 ppt Water clarity: 94% Coral cover: 49% Total fish species: 442
FINISH ACTIVITY A TODAY
, Get the Gizmo ready:
Activity A:
On the CONDITIONS tab, click Return to original
The Caribbean
settings. Click Restart.
reef ecosystem
Select the CORAL REEF tab.
Introduction: A healthy Caribbean reef is home to over 50 species of coral and over 400 fish
species. In this simplified model, we only consider the interactions of ten important species.
Question: How do different species interact in a healthy coral reef?
1. Describe: On the CORAL REEF tab, click on each organism shown in the table below. For
each organism, give its name and what it eats (or how it obtains energy).
Picture Name What it eats (or how it obtains energy)
Staghorn Coral photosynthetic symbiotic algae
Boulder Star Coral photosynthetic symbiotic algae
plankton
Sponge
sun
Algae
Stoplight Parrotfish algae
sponges
Queen Angelfish
Yellowtail Snapper young fish, crabs, shrimp, and worms
Nassau Grouper many reef fish
Long-spined Sea Urchin algae
Hawksbill Sea Turtle sponges
2. Corals obtain energy from tiny photosynthetic algae, called zooxanthellae, which live inside
the coral’s tissue. How do you think corals would be affected by cloudy, muddy water?
Their food supply would be low because the cloudy, muddy water would block the sun from
reaching it
(Activity A continued on next page)
Student Exploration: Coral Reefs 1 – Abiotic Factors
Vocabulary: consumer, coral, coral bleaching, coral reef, filter feeder, food chain, food web,
grazer, nutrients, ocean acidification, pH, plankton, predator, producer, sediment, zooxanthellae
Prior Knowledge Questions (Do these BEFORE
using the Gizmo.)
1. Look at the graph to the right. What does it show?
Percentage of coral cover in Caribbean Reefs. It
shows a decline over time.
2. Why do you think corals have declined since 1977? People are killing and selling them.
Gizmo Warm-up
Coral reefs are some of the most diverse habitats on
Earth, home to over a quarter of all marine species. The
Coral Reefs Gizmo™ provides a simplified model of
interactions among 10 key species in Caribbean reefs. In
the Coral Reefs 1 exploration, you will focus on the effects
of environmental factors on Caribbean reefs.
1. Click Advance year 10 times. Look carefully at the composition of the reef over time. Do
you see any major changes? The reef stayed consistent.
2. Select the DATA tab. Check that Staghorn coral, Star coral, Sponges, and Algae are
selected. Populations are given as a percentage of normal populations.
What do you notice about these populations? Sponges poulation goes up while the others don't.
3. On the right side of the Gizmo, select the SUMMARY tab. In a healthy reef, what are the
values for Nutrient load, Water clarity, Coral cover, and the total number of fish species?
Nutrient load: 4 ppt Water clarity: 94% Coral cover: 49% Total fish species: 442
FINISH ACTIVITY A TODAY
, Get the Gizmo ready:
Activity A:
On the CONDITIONS tab, click Return to original
The Caribbean
settings. Click Restart.
reef ecosystem
Select the CORAL REEF tab.
Introduction: A healthy Caribbean reef is home to over 50 species of coral and over 400 fish
species. In this simplified model, we only consider the interactions of ten important species.
Question: How do different species interact in a healthy coral reef?
1. Describe: On the CORAL REEF tab, click on each organism shown in the table below. For
each organism, give its name and what it eats (or how it obtains energy).
Picture Name What it eats (or how it obtains energy)
Staghorn Coral photosynthetic symbiotic algae
Boulder Star Coral photosynthetic symbiotic algae
plankton
Sponge
sun
Algae
Stoplight Parrotfish algae
sponges
Queen Angelfish
Yellowtail Snapper young fish, crabs, shrimp, and worms
Nassau Grouper many reef fish
Long-spined Sea Urchin algae
Hawksbill Sea Turtle sponges
2. Corals obtain energy from tiny photosynthetic algae, called zooxanthellae, which live inside
the coral’s tissue. How do you think corals would be affected by cloudy, muddy water?
Their food supply would be low because the cloudy, muddy water would block the sun from
reaching it
(Activity A continued on next page)
