1. Kelp Forest Food Web Activity
Objectives:
To learn about interesting kelp forest organisms
To learn how to look for specific information in paragraphs
To categorize organisms according to trophic level
To create and interpret a food web
To determine how various events and disturbances impact the food web
Materials:
Kelp Forest Critter Cards (4 single-sided pages)
Scissors
Glue or tape
Colored pencils or pens
Large piece of paper
Highlighter
Organisms:
Procedure:
Read the information on each species and highlight what it eats.
Write on the card which organisms in the food web it eats.
Using the information provided, write each organism’s ecological role on the line below its name on the card: producers, primary consumers (herbivores), secondary/tertiary consumers (carnivores), decomposers. Note that some organisms may fill two roles. The Sun’s ecological role is “ultimate energy source”
Carefully cut out the cards (left side of table).
Move the cards around to create a food web for the following organisms. The decomposers eat all organisms, so they should be off to one side under the heading “Decomposers.”
Add the card for the Sun in the appropriate place.
Glue or tape down the cards. Draw arrows to show the flow of energy from each organism to the organism(s) that eat it (pointing toward the consumer – example: grass → deer).
Answer the questions on the next page.
Bald Eagle
Bat Star
California Sheephead
Decorator Crab
Giant Kelp
Phytoplankton
Purple Sea Urchin
Red Abalone
Sea Cucumber
Sea Otter
Spiny Brittle Star
Sunflower Star
White Shark
Zooplankton

2. Kelp Forest Food Web Activity
Name: ___________________
Period: ___________________
Kelp Forest Food Web Activity
Questions:
As sea otters recover and become more numerous throughout California, what do you predict is happening to the number of sea urchins? Amount of giant kelp?
If a huge storm wipes out all the kelp, what happens to the other organisms in the community?
La Nina events bring particularly cold water with lots of nutrients, causing kelp and phytoplankton to grow very well. For organisms that will increase in number or biomass, outline the card in blue. For organisms that will decrease in number or biomass, outline the card in red.
In Alaska, orcas (killer whales) have begun eating lots of otters because their normal prey (seals, sea lions, whales) are less numerous. What do you expect is happening to the otter population? Sea urchin population? Kelp population?
In addition to energy, proteins, vitamins, minerals, and chemicals are passed from one organism to another. From 1947 to 1983, a chemical plant dumped 1,700 tons of DDT (an insecticide) off the coast of Southern California. Because it dissolves in the fat of animals, DDT builds up in the body of animals even if they do not die. DDT is taken up by kelp and phytoplankton and accumulates in the bodies of the organisms that eat the kelp and phytoplankton. Which species on this food web will have the highest amount of DDT in their bodies?

3. Bald Eagle Haliaeetus leucocephalus
Bald eagles are not actually bald, but have white heads and brown bodies. They scavenge many meals by harassing other birds or by eating dead animals or garbage. They eat mainly fish, but also hunt mammals (including sea otter pups), gulls, and waterfowl. The bald eagle has been the national emblem and bird of the United States since They usually live near the ocean or large bodies of freshwater with lots of fish. They have recovered from being endangered in the early 20th century by hunting and pesticides.
Bald Eagle
____________________
Bat Star Patiria miniata
[size: to 8 in. (20 cm)]
Bat stars come in a wide variety of solid and mottled colors, including red, orange, yellow, brown, green and purple. They have webbing between their 5 (or sometimes more) short, triangular arms, which gives them a batlike look. They eat algae (like kelp) and small animals (like tubeworms), but mostly scavenge dead animals on the bottom. Like all sea stars, a bat star’s stomach can come out of its mouth and cover its food to eat.
MBA - Kelp Forest Critter Cards
Bat Star
____________________
California Sheephead Semicossyphus pulcher
[size: to 3 ft (91 cm)]
Sheephead swim above rocky areas and are eaten by bald eagles, sea lions, harbor seals, and humans. They are all born female, but turn into males when they grow to about 12 inches (7 or 8 years old). They also change color from red to red and black with white chins. Sheephead eat snails, crabs, urchins, and other invertebrates. They are now rare because they are often targeted by spear fishermen. They can live up to 50 years.
MBA – KelpForest Critter Cards
California Sheephead
____________________
Decorator Crab Loxorhynchus crispatus
[size: to 3.5 in. (8.8 cm)]
A decorator crab camouflages its shell with algae, sponges, and other things that grow on local rocks. When the crab sheds its outer skeleton to grow larger, it has to redecorate. Decorator crabs eat sea urchins, small crustaceans, and sponges. Decorator crabs are an important food source for some fishes, including croakers and cabezon.
MBA – Kelp Forest Critter Cards
Decorator Crab
____________________

4. Giant Kelp Macrocystic pyrifera
[size: to 175 ft tall (53 m)]
Like trees of the sea, giant kelp (a type of marine algae) conducts photosynthesis and creates its own ecosystem that hosts many fishes, invertebrates, and other organisms. Held upright by gas-filled bladders, kelp fronds grow inches per day straight up to the surface, where they form a dense canopy. Its stems are tough but flexible, allowing the kelp to sway. Like a plant’s root system, the holdfast anchors the kelp to a rock. Kelp is harvested for use in foods such as ice cream and toothpaste.
Giant Kelp
_________________
Phytoplankton [size: 2×10−6- 2×10−4 m]
Phytoplankton are photosynthesizing microscopic organisms that inhabit the upper sunlit layer of almost all oceans and bodies of fresh water. Although too small to be individually seen without a microscope, when present in high enough numbers, they may appear as a green discoloration of the water due to the presence of chlorophyll within their cells. Phytoplankton account for half of all photosynthetic activity on Earth and much of the oxygen present in the Earth's atmosphere. They are limited by nutrients, such as nitrogen and phosphorous.
Phytoplankton
____________________
Purple Sea Urchin Strongylocentrotus purpuratus
[size: to 4 in. (10 cm)]
A sea urchin looks like a pin cushion because it has a round inner shell, called a “test,” covered with spines, pincers, and tube feet. The spines spear kelp and protect an urchin from predators. An urchin uses its many tube feet to move, hold onto rocks, and move food to its mouth. During a population surge, sea urchins—which normally eat pieces of kelp that fall to the seafloor—will feed on the stipes of giant kelp plants and can completely destroy a kelp bed.
MBA – Kelp Forest Critter Cards
Purple Sea Urchin
____________________
Red Abalone Haliotis rufescens
[size: to 11.8 in. (30 cm)]
Red abalone, a type of snail, live in crevices, rarely moving far from a chosen spot on the rock. The holes in the shell are outlets for water circulation. When their tentacles sense a large pieces of drifting kelp, the abalone rears toward it, then grabs the seaweed with its big foot. Due to overfishing and disease, today abalone face extinction (the white abalone is officially endangered), so commercial fishing is not allowed and there are very strict rules for sport fishing.
MBA – Kelp Forest Critter Cards
Red Abalone
____________________

5. Sun Sea Cucumber Parastichopus californicus Sea Cucumber
[size: to 16 in. (40 cm)]
Relatives of the sea stars and urchins, sea cucumbers have soft bodies and look like a big worm. They swallow sand and mud and filter out food particles from dead organisms. They move very slowly and are eaten by humans in some Asian cultures. When a predator attacks a sea cucumber, it can shed its sticky internal organs, which entangle and distract the predator while the sea cucumber escapes. The shed organs soon grow back.
MBA – Kelp Forest Critter Cards
Sea Cucumber
____________________
Sea Otter Enhydra lutris
[size: to 5.5 ft (1.7 m)]
Hunters nearly drove sea otters extinct in the 1700s and 1800s, but they’ve recovered to nearly 2000 in California waters today. For warmth, the sea otter relies on its thick fur coat and burns calories at nearly three times the rate you do! An otter fuels its fast metabolism by eating up to a quarter of its weight in food every day. The otter dives for food and then eats it lying on its back at the surface. It consumes many small animals like abalone, snails, sea urchins, and crabs.
MBA – Kelp Forest Critter Cards
Sea Otter
____________________
Spiny Brittle Star Ophiothrix spiculata
[size: to 5.7 in. (14.4 cm)]
Brittle stars hide among rocks and in the rootlike kelp holdfasts, anchored into cracks by their long spines. Their delicate arms break easily, but also grow back quickly. They catch suspended food particles and plankton by waving their arms through the water. Small tube feet on each arm transfer the food to the mouth. They also scavenge detritus and dead things from the bottom. A single holdfast may house hundreds of brittle stars!
MBA – Kelp Forest Critter Cards
Spiny Brittle Star
____________________
Sun
The sun is the star at the center of Earth’s solar system. It is located 149.6 million kilometers from Earth (8 min 19 s at light speed). By fueling photosynthesis of plants, algae, and phytoplankton, the sun is the ultimate source of energy on Earth.
Sun
_____________________

6. Sunflower Star Pycnopodia helianthoides
[size: to 39 in. (1 m)]
An array of 24 arms distinguishes this magnificent sunflower star from other sea stars. Soft skin in colors ranging from purple to brown, orange or yellow adds to its beauty. This sea star is a voracious predator - feeding on sea urchins, mussels, crabs, sea cucumbers, snails, brittle stars, and more. When on the prowl for food using their strong sense of smell and very sensitive indicators of light and dark, the sunflower star can move at the remarkable speed of over 40 inches (1 m) per minute.
michiganscienceart.com
Sunflower Star
____________________
White Shark Carchardodon carcharias
[size: to 30 ft (9.1 m)]
At any one time, a white shark has more than 3,000 razor-sharp teeth arranged in rows. It uses the first two rows to grab food and rotates the other rows in as teeth are lost. White sharks eat fishes, sea birds and mammals (such as sea otters), turtles and invertebrates. Like all sharks, the white shark has no bones; its skeleton is made of cartilage, the same tissue that gives shape to our ears and nose. Their torpedo-shaped bodies and symmetrical tails are adaptations for efficient swimming.
MBA – Sharks & Rays Critter Cards
White Shark
____________________
Zooplankton [size: > 2×10−7  m]
Zooplankton are non-photosynthesizing organisms drifting in oceans, seas, and bodies of fresh water.  Individual zooplankton are usually too small to be seen with the naked eye, but some species are very big such as jellyfish and squid. Ecologically important zooplankton include foraminiferans, radiolarians, copepods, krill (all on card), and many juvenile fishes and invertebrates. Like phytoplankton, zooplankton are distributed in patches restricted by temperature and salinity gradients. Most zooplankton eat smaller phytoplankton.
Various
Zooplankton
____________________

7. Kelp Forest Food Web Activity
KEY
Questions:
As sea otters recover and become more numerous throughout California, what do you predict is happening to the number of sea urchins? Amount of giant kelp?
Sea otters increase → sea urchins decrease → kelp increase
If a huge storm wipes out all the kelp, what happens to the other organisms in the community?
No kelp → no community until it starts to recover through ecological succession
Phytoplankton, zooplankton, brittle stars, sunflower stars may survive
La Nina events bring particularly cold water with lots of nutrients, causing kelp and phytoplankton to grow very well. For organisms that will increase in number or biomass, outline the card in blue. For organisms that will decrease in number or biomass, outline the card in red.
All are blue!! Since kelp and phytoplankton are bottom of food web, if they increase, everything increases!
In Alaska, orcas (killer whales) have begun eating lots of otters because their normal prey (seals, sea lions, whales) are less numerous. What do you expect is happening to the otter population? Sea urchin population? Kelp population?
Otters decrease → urchins increase → kelp decrease
In addition to energy, proteins, vitamins, minerals, and chemicals are passed from one organism to another. From 1947 to 1983, a chemical plant dumped 1,700 tons of DDT (an insecticide) off the coast of Southern California. Because it dissolves in the fat of animals, DDT builds up in the body of animals even if they do not die. DDT is taken up by kelp and phytoplankton and accumulates in the bodies of the organisms that eat the kelp and phytoplankton. Which species on this food web will have the highest amount of DDT in their bodies?
Top predators – bald eagle, white shark, sheephead, otter

8. Kelp Forest Food Web Activity
KEY
Kelp Forest Food Web Activity
Decomposers
Spiny Brittle Star
Sea Cucumber
Bald Eagle
White Shark
Bat Star
California Sheephead
Sea Otter
Sunflower Star
Decorator Crab
Spiny Brittle Star
Purple Sea Urchin
Red Abalone
Zooplankton
Giant Kelp
Phytoplankton
Sun

9. Kelp Forest Food Web Activity
KEY
Kelp Forest Food Web Activity
Organism
Trophic Level
Bald Eagle
Bat Star
California Sheephead
Decorator Crab
Giant Kelp
Phytoplankton
Purple Sea Urchin
Red Abalone
Sea Cucumber
Sea Otter
Spiny Brittle Star
Sun
Sunflower Star
White Shark
Zooplankton
Tertiary consumer
Detritivore/Decomposer
Secondary/tertiary consumer
Secondary consumer
Producer
Primary consumer
Secondary consumer, detritivore/decomposer

10. Kelp Forest Energy Pyramid
Objectives:
To create an energy pyramid with trophic levels
To show transfer of energy from the sun and to heat
To show the efficiency of energy transfer between trophic levels
Materials:
Completed kelp forest food web activity results (or cards showing trophic level)
Grid
Colored pencils of pens
Glue or tape
Procedure:
Label x-axis as “Units of Energy in Each Trophic Level.
Label y-axis as “Trophic Level”
Label the bottom trophic level, which covers 100 squares, symbolizing 100 units of energy..
Sketch with appropriate size 3 higher trophic levels, assuming 10% energy transfer efficiency.
Color and label each trophic level as below.
Trophic Level Color
Producers green
Primary consumers (herbivores) blue
Secondary consumers (carnivores) orange
Tertiary consumers (apex predators) red
Tape next to the appropriate trophic level each of the cards below.
Use colored arrows to show how the physical environment (sun and heat) interact with the energy pyramid.

11. Kelp Forest Energy Pyramid

12. Kelp Forest Energy Pyramid
KEY
Kelp Forest Energy Pyramid
Trophic Level
Tertiary Consumers
Secondary Consumers
Primary Consumers
Producers
Units of Energy in Each Trophic Level