M-06: INTERTIDAL BANNER
MATERIALS LIST:
Banner
A map of the North American Continent
Velcro backed laminated photos of plants and animals in five baggies
A few representative preserved tidal zone specimens
ZONE I
ZONE II
SPLASH, OR SPRAY ZONE
HIGH TIDE ZONE
Bagggie with Yellow Spot
Bagggie with Red Spot
a. Sea Spaghetti
a. Rockweed
b. Periwinkles, Barnacles & Limpets
b. Sea Lettuce
c. Barnacles (see also Red #8)
c. Nail Brush
d. Limpet (see also Green #8)
d. Sea Stacks
e. Beach Hopper
e. Hermit Crab
f. Black Turban Snail
g. Aggregated Sea Anemones
h. Barnacles (see also Yellow #3)
i. Lined Shore Crab
ZONE II
MID TIDE ZONE
Baggie with Green Spot
a. Iridaea
b. Nori
c. Surf Grass
d. Coralline Algae
e. Ochre Stars
f. Goose (neck) Barnacles & Mussel Colony
g. Mussels
h. Limpet (see also Yellow #4)
i. Mossy Chiton
j. Brittle Star
k. Green Sea Anemone
l. Sculpin
m. Goose Barnacle
n. Purple Shore Crab
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ZONE IV
LOW TIDE ZONE
Baggie with Blue Spot
a. Oarblade Kelp
b. Sea Palms
c. Leather Star
d. Bat Star
e. Rock Crab
f. Purple Sea Urchin
g. Abalone
h. Sponge
i. Nudibranch
j. Brown Turban Snail
k. Kelp Crab
SUBTIDAL ZONE
Baggie with Orange Spot
Sunflower Star
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INTERTIDAL BANNER
Source: Bobbie Callison, Lenore Carney
M—06
OBJECTIVES:
Students will:
• be able to identify the distinguishing characteristics of the intertidal community and its zones.
• become familiar with some plant and animal species which can be found in the four zones of
the intertidal community .
• have a general idea of hazards (environmental controls) to intertidal life and adaptive
mechanisms for protection.
• be exposed to biological classification of intertidal community invertebrates.
SCIENCE THEMES:
Evolution, patterns of change, energy, stability, systems and interaction
PROCESS SKILLS:
Comparing, categorizing, ordering
GRADE LEVELS:
3–6
FOSCUS WORDS:
ADAPTATION
HERVBIVORE
PREDATOR
ALGAE
HIGH TIDE ZONE
SALT WATER
ARTHROPODS
INDICATOR SPECIES
SCAVENGER
CNIDARIANS
INTERTIDAL COMMUNITY
SPLASH ZONE
COAST
INVERTEBRATE
SUBTIDAL ZONE
CONTINENT
LOW TIDE ZONE
SUBMERSION
DESSICATION
MARINE
SURGE CHANNEL
DETRITUS
MID TIDE ZONE
TERRESTRIAL
EXPOSURE
MOLLUSCANS
TIDE
FRESH WATER
NICHE
TIDAL ZONES
FILTER FEEDING
OCEAN
TIDE POOLS
HABITAT
PHYLUM
UPWELLING
PLANKTON
VERTEBRATE
BACKGROUND INFORMATION:
The Intertidal Banner consists of the banner, with the lifeless intertidal region depicted in Velcrofriendly cloth and a gossamer blue fabric representing the water level, and laminated Velcro-backed
photos. These photos, labeled on the back and marked with a color code for the most appropriate
tidal zone, will be placed on the banner by the students as discussion of the intertidal community
takes place. There are four tide pools on the banner, arranged vertically. We chose not to delineate
firm zone boundary lines, but suggest that one tide pool per zone works well. (The top pool in the
splash zone is shallow and drying up.)
The banner and this script are designed for teaching flexibility. It may not be feasible or appropriate
to use it at all. Indeed, as time passes, plant and animal photos may be added without corresponding
inclusion in the script. They will, however, be zone color coded.
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The script is only a suggestion. It is intended to orient students who have little or no familiarity with
the marine ecosystem and might be going to Fitzgerald Marine Reserve, Moss Beach or Natural
Bridges with their parents.
Also included is a map of the North American continent for orientation purposes and some preserved
specimens of animals found in intertidal zones.
For older/more experienced classes, placement of plants and animals may go quickly and the
remainder of the time can be spent looking in some detail of food webs, adaptations, as well as the
presence of shore birds, fresh water (creeks, heavy rainfall), human development, etc.
ACTIVITY:
Mix up all of the laminated photos. Have each student take one photo at random. There are 38
photos so there are probably enough to give some students more than one. Ask who has photo
Yellow #1, the first one to be put on the banner, and give that person another draw. Then ask who
has photo Orange #1, The last photo to be put on the banner and give that person another draw.
Continue this way until all the photos are passed out. Students should put the photos on the desk or
table in front on him/her, with the face down so the number and colored spots show.
Step One: Geographical Orientation and Focus on Target Community
The beach is the place where the land meets the OCEAN. The land meets the ocean at the edges
of a CONTINENT. We call that the COAST of the continent.
Point to the map of the North American Continent and outline the coasts with your pointer.
Most of the states of our country do not have land which meets the ocean, but because California
is on the western edge of the North American CONTINENT, people who live in California are
on or near a coast.
What ocean is California on the coast of?
We are on the coast of the Pacific Ocean, so we call our coast the PACIFIC COAST.
Point to California on the map.
When we go to the beach, where the SALT WATER ocean meets the land, we see that
sometimes the beach is wider and sometimes it is narrower. We find that the ocean varies as to
how far up the edge of the continent it comes at different times of the day, at different times of
the month, and at different times of the year. This movement is called "the TIDE."
Point to the Intertidal Banner.
This banner is a model of a piece of the coast. This light blue curtain represents the ocean. I can
make the tide come in, "FLOOD," and go out, "EBB." When the tide is as far up the beach as it
will go on this cycle it is called HIGH TIDE. When it is as far down it is called LOW TIDE.
Show high tide and low tide on the banner by raising and lowering the light blue curtain which
represents the water of the ocean.
The special area of the coast which is EXPOSED sometimes and SUBMERGED other times is
called the INTERTIDAL COMMUNITY. Northern California has a particularly diverse intertidal
community because of UPWELLING, the constant arrival of cold, nutrient-rich ocean bottom
water. This community, or HABITAT, is divided into sections called TIDAL ZONES.
Move the curtain to cover all but the SPLASH ZONE.
The area that is almost always exposed to the sun we label ZONE I and call it the SPLASH
ZONE. It gets some splash and spray when the tide is the highest, maybe only six to eight times a
year.
Move the curtain down to expose the HIGH TIDE ZONE.
This is the area that is exposed to the sun as much as 75% of the time, but it gets submerged at
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least once a day. It is known as the HIGH TIDE ZONE, and we label it as ZONE II.
Move the curtain down to expose the MID TIDE ZONE.
This area is submerged most of the time, but gets exposed at least once a day. It is called the MID
TIDE ZONE, and is labeled as ZONE III.
Move the curtain down to expose the LOW TIDE ZONE.
This area is exposed only when the tides are the lowest. It may not be exposed at all on some
days. It is called the LOW TIDE ZONE, and is labeled as ZONE IV.
Within each zone are special habitat areas, such as sand, rocks, rock crevices and pools of
trapped ocean water called TIDE POOLS.
Point to corresponding places on the banner as you mention them.
People who visit the coast to see the creatures of the tidal zones are said to be "tidepooling." Let's
stop and think for a minute, about the life of the plants and animals in the intertidal community.
Imagine being able to survive periods under water AND periods exposed to sun, wind, shore
birds and TIDE POOL VISITORS! At any given time would you be wet or dry? Cool or warm?
Hidden or visible? Near your food or away from it? We must always be aware of the
environmental controls on the populations of living things we are about to examine.
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Step two: Plants and Animals of the Intertidal Community
When you go tidepooling, you may start on a sandy beach along which you will see many things
washed up by the waves. Look carefully at what is there. You may see some kelp rotting and
smelly, a favorite hang-out for the small shrimp-like BEACH HOPPER (photo #5 Yellow ).
You may see driftwood and parts of shells, broken, then worn smooth by the wave action of
water against the sand. Look carefully, for all of this is a collection of clues about life near the
shore.
You may notice some cliffs, or bluffs, or large rock outcrops which the ocean reaches some of
the time. This is where Zone I, the Splash Zone, begins. You know you are there if you see the
plant which grows ONLY in Zone I — that zone's INDICATOR SPECIES.
The plant that grows only in the splash zone, the INDICATOR SPECIES, is SEA SPAGHETTI,
photo #1 Yellow.
The student with that photo will read the name and place it on the banner.
Near the SEA SPAGHETTI you may notice a variety of small animals, and they may show up
more clearly if the area is still wet from its latest splashing. These are PERIWINKLES, small
BARNACLES, and LIMPETS (photo #2 Yellow).
The student with that photo will read the name and place it on the banner.
The barnacles are FIILTER FEEDERS. They filter microscopic organisms called PLANKTON
from the water and PERIWINKLES and LIMPETS "graze" on a thin algae film covering the
rocks. Because these animals are exposed to the heat of the sun most of every day they must be
able to prevent DESSICATION; drying out. To prevent DESSICATION they must clamp down
tight to the rock and close all of the openings in their shell to trap their moisture inside. They can
only feed when things are wet.
Barnacles (photo #3 Yellow which also has a Red sticker #8) live on rocks and other hard
surfaces in both the splash zone and the high tide zone; that's why there are two colored stickers
on the photo. They do not live in sand or mud.
The student with that photo will read the name and place it on the banner.
Limpets (photo #4 Yellow and Green #8) live on rocks and other hard surfaces all the way from
the splash zone to the mid tide zone. They do not live in sand or mud.
The student with that photo will read the name and place it on the banner.
The BEACH HOPPER (photo #5 Yellow) can usually be found near the decaying sea weed.
The student with that photo will read the name and place it on the banner.
Lower the curtain to expose ZONE II the HIGH TIDE ZONE.
The indicator plant for ZONE II is called ROCK WEED (photo #1 Red). Where do you think it is
found?
The student with that photo will read the name and place it on the banner.
Another plant you might see in this zone is called SEA LETTUCE (photo #2 Red).
The student with that photo will read the name and place it on the banner.
A dark plant so short and stiff you might be able to clean your finger nails with is called NAIL
BRUSH (photo #3 Red).
The student with that photo will read the name and place it on the banner.
You will recognize Sea Stack (photo #4 Red) because it looks like tan, elongated water balloons.
It is found on the rocks in the high tide zone.
The student with that photo will read the name and place it on the banner.
When looking into a tide pool you might see a BLACK TURBAN SNAIL (photo #6 Red). It will
be motionless on the bottom. But, then along side of it you might see another BLACK TURBAN
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SHELL and this one is walking on crab-like legs. This one is a HERMIT CRAB (photo # 5 Red).
The TURBAN SNAIL is an HERBIVORE feeding on algae or kelp, where the HERMIT CRAB
is a scavenger, whose job, or niche, is to keep the pool clean. The HERMIT CRAB does not
have a shell to protect its soft abdomen, so it borrows an empty snail shell that fits and slips into
it. It carries the shell around for its mobile, protective house. When it grows too big for the
shell it has been using, it goes shopping for a larger one.
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The students with that photos will read the names and place them on the banner.
If you find what looks like a sandy patch on the side of a rock in Zone II, gently touch it. If it is
soft you have found a colony of AGGREGATING ANEMONE (photo #7 Red). These
ANEMONE gather together in large colones. As wind and waves carry grains of sand or bits of
shell to the animone, they stick to it and give it protection against the hot sun when the tide is
out.
The student with that photo will read the name and place it on the banner.
Do you remember, up in the SPLASH ZONE we had a photo of BARNACLES that had a yellow
spot and a red spot. That was because those barnacles are also down here in the high tide zone.
They are attached to the rock with barnacle "super-glue," so waves and even birds cannot move
them.
As you are looking closely at those barnacles, your attention might be drawn downward to the
crevice beneath the rock and tiny eyes looking back at you. They belong to the LINED SHORE
CRAB (photo #9 Red).
The student with that photo will read the name and place it on the banner.
Lower the curtain to expose ZONE III the MID TIDE ZONE.
As the tide goes out we will be able to walk farther down the beach into the MID TIDE ZONE.
Here we will see a soft, iridescent seaweed floating in the shallow pools or strewn on the rocks.
Because this IRIDAEA (photo #1 Green) is the indicator for Zone III you know you have reach
the MID TIDE ZONE.
The student with that photo will read the name and place it on the banner.
Another plant you might see are the shiny NORI (photo #2 green). This is cultivated as a food
plant in Japan.
The student with that photo will read the name and place it on the banner.
You may see SURF GRASS (photo #3 Green). Surf Grass is not a real seaweed, but as the name
implies, it is a grass.
The student with that photo will read the name and place it on the banner.
CORALLINE ALGAE (photo #4) is hard and brittle, and does not resemble what we think of as
algae. When it is living it is a delicate pink color, but when it is washed up on the beach it has
bleached to white.
The student with that photo will read the name and place it on the banner.
The OCHRE STAR (photo #5 Green) is one of the common kinds of sea star. We do not use the
term "starfish" because they are not fish. Ochre stars are found in two colors, as seen in the
photo. You may see them near MUSSELS, their favorite food.
The student with that photo will read the name and place it on the banner.
Photo #6 Green shows the white GOOSE BARNACLES near the MUSSELS. The MUSSELS
and GOOSE BARNACLES both enjoy the same environment and can live tightly packed
together. Mussels and Barnacles, and many other animals, are filter feeders. To them the ocean is
one large bowl of soup with enough microscopic food particles in it for everybody. MUSSELS
and GOOSE BARNACLES both close up tightly when exposed to prevent DESICCATION.
When you look at the photo of the barnacle you can see why they are sometimes called
GOOSENECK BARNACLES.
The student with that photo will read the name and place it on the banner.
MUSSELS (photo #7 Green) live in tightly packed colones. They are firmly attached to rocks or
other hard surfaces by their BYSSAL FIBERS. These fibers stick firmly to the rocks so that
ocean breakers, birds and sea stars have a hard time dislodging them.
The student with that photo will read the name and place it on the banner.
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When we were in the SPLASH ZONE we had a photo with a yellow spot and a green spot. This
is because the LIMPET (photo #8 Green & #4 Yellow) lives in the HIGH TIDE ZONE and the
MID TIDE ZONE as well as in the SPLASH ZONE.
The student with that photo will read the name and place it on the banner.
The MOSSY CHITON (photo # 9 Green) is a mollusk with eight shell plates each shaped like a
butterfly. The shells are often comouflaged with seaweed. They move around when submerged.
We won't disturb the chiton when we see one, remembering that this is their home, and we are
visitors.
The student with that photo will read the name and place it on the banner.
The BRITTLE STAR (photo #10 Green) is a tiny and delicate animal who hides under rocks. It is
a DETRITUS feeder, eating decaying organic matter. If you should turn over a rock and find one
you should take a quick look and then carefully replace the rock.
The student with that photo will read the name and place it on the banner.
Is the GIANT GREEN SEA ANEMONE (photo #11 Green) a plant or an animal? It looks like a
flower, but it is actually an animal, a stinging celled predator which eats other animals. But it is
also a bit of a plant; the green color is caused by tiny algae which actually live inside the animal's
transparent tissue using sun's light energy for PHOTOSYNTHESIS!
The student with that photo will read the name and place it on the banner.
If you should stare into a tide pool looking for all the different plants and animals you will
probably not see a fish, but then there might be a quick movement from one place to another.
You follow that movement and find a very well camouflaged little fish that is perfectly
stationary. You have just found a SCULPIN (photo #12 Green); the only VERTEBRATE that
commonly inhabits tide pools.
The student with that photo will read the name and place it on the banner.
The next photo (photo # 13 Green) is another photo of the GOOSE BARNACLE. This photo
gives a better view of what this BARNACLE looks like.
The student with that photo will read the name and place it on the banner.
The PURPLE SHORE CRAB scampers behind rocks and in rock crevasses in middle and low
tide zones.
The student with that photo will read the name and place it on the banner.
Lower the curtain to expose ZONE IV the LOW TIDE ZONE.
We will now enter the LOW TIDE ZONE, this is ZONE IV. Here the rocks are slippery, and we
must be careful. This is as far as people can go without getting wet. Here we find OAR BLADE
KELP (photo #1 Blue) floating in pools nearby, indicating the Low Tide Zone, Zone IV
The student with that photo will read the name and place it on the banner.
On the rocks nearby you will see what looks like small wet palm trees. These are called SEA
PALMS (photo #2 Blue),
The student with that photo will read the name and place it on the banner.
In the Low Tide Zone we find two kinds if SEA STAR, The smooth backed one is the
LEATHER STAR (photo #3 Blue), and the webbed looking one is the BAT STAR (photo #4
Blue).
The students with those photos will read the names and place them on the banner.
If you look in the crevice you might see the ROCK CRAB (photo #5 Blue), scavenging after
anything he can find to eat, earning his reputation as the intertidal garbage collector.
The student with that photo will read the name and place it on the banner.
In the SURGE CHANNEL, the rocky crevice into which the waves are now flowing, there are
spiny PURPLE SEA URCHINS (photo #6 Blue), safely fitting into depressions in the rock.
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In the LOW TIDE ZONE you might notice a large ABALONE (photo #7 Blue) attached in the
style of the smaller limpets and chitons you have already seen.
The student with that photo will read the name and place it on the banner.
If the tide is especially low, you may see a colony of SPONGE (photo #8 Blue) lining the wall of
a rock which is nearly always submerged.
The student with that photo will read the name and place it on the banner.
You may also see a NUDIBRANCH, (photo #9 blue) also known as a SEA SLUG. It is a snail
which has no shell. Since it is very bad tasting, it does not need a shell for hiding from predators.
The student with that photo will read the name and place it on the banner.
In this zone you will also see the BROWN TURBAN SNAIL (photo #10 Blue) and the KELP
CRAB (photo #11 Blue). The KELP CRAB is one of the few herbivorous crabs.
The students with those photos will read the names and place them on the banner.
Look just beyond. You see water covering a descending continental shelf. Some call this the
SUB TIDAL ZONE. If you could see under the surface of the water you would see more abalone
and sponge. You would see a SUNFLOWER STAR (photo #1 Orange) with many more than 5
arms, in fact it can have as many as 20 arms. and you would see the red sea urchin and
vertebrates such as rock fish. If, someday, you will become the kind of scientist who studies
these areas, you will be called a MARINE biologist. Even before then, you may discover that
there are many more plant and animal species in the intertidal community than those we have
looked at this morning. There are marine worms, small shrimp relatives, and many, many more.
Studying the food web is very interesting.
Part Three: Biological Classification of Familiar Intertidal Animals
Did you notice that almost all of the animals we have talked about are INVERTEBRATES,
meaning animals without backbones? You probably know that biologists group animals with
similar characteristics together, but you may be surprised to learn which animals are "relatives."
For example, would you believe that the sea stars and the sea urchins are in the same PHYLUM?
They are both in the phylum for ECHINODERMS, or spiny-skinned animals. It took scientists a
long time to discover that barnacles have jointed legs, so they are in the same group as all of the
crabs and other jointed legged animals, called the ARTHROPODS.
Remember all of those soft bodied animals with one or two shells, which include the snails,
limpets, chitons, mussels, and abalone, are called the MOLLUSCANS. Does anyone remember
the relative of these animals who has no shell? Hint: it tastes bad (nudibranch).
As you can imagine, all of the anemones, big and small, are in the same phylum because they all
have stinging cells. They are the CNIDARIANS (as are the by-the-wind-sailors you may see
blown onto the beach in the spring).
Perhaps, at another time, you can study FRESH WATER and land dwelling, or TERRESTRIAL
relatives of intertidal creatures, but that is for later.
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