Tidepool Activities -- PreK-2

Pre Visit Goals HABITAT  - Identify and appreciate the extreme changes constantly taking place in the tidepool environment:  High/low tide, wet/dry, cool/warm   CLASSIFICATION - Living vs. Non living tidepool finds ADAPTATION -  Camouflage Visit Goals HABITAT – Identify characteristics of marsh, dune and tidepool CLASSIFICATION – Scavenger hunt helps group animals (Ex. “find three animals that have a shell”) ADAPTATION – Observe examples of camouflage, holding on, closing up, hiding, etc Post Visit Goals HABITAT - Mud, Sand and Rocks CLASSIFICATION - Mobile vs. Sessile animals ADAPTATION -  Holding on, Staying Moist, Protection from Predators

Pre Visit

HABITAT – Identify the characteristics of a tidepool habitat.  Appreciate the extreme environmental changes that take place as the tide goes in and out. 

Activity:

Tidal fluctuations are a repeating pattern in nature.  Discover the similarities and differences in a given area during high tide and low tide. 

1. Give children a simple picture of a rocky shoreline.  Have children indicate the water level at the top.  What goes on under the water?  Barnacles extend their feather-like feet for feeding.  Mussels open slightly to feed.  Sea stars, periwinkles crabs, and fish move about under the water.  Large fish may be found.  Algae floats and sways with the water’s movement.  Birds fly overhead.  Affix appropriate cutouts to the appropriate areas on the picture and color. 
2. Give children a second picture identical to the first.  Now indicate a low water level, so that only the pools are filled with water.  Now where are the animals and algae?  How are they behaving?  Barnacles and mussels are closed up tight, still on their rocks.  Crabs hide under rocks.  Dry periwinkles hold on tight and stop moving.  Moving periwinkles, sea stars, and fish gather in the wet spots.  Algae sits limp and motionless.  Large fish have retreated to deeper waters.   Birds walk around, hunting for food.   Affix cutouts and color. 
3. Discuss the differences in these pictures.  Which situation is the most wet/dry?  The coolest/warmest?  Which is the best time to hunt for food?  (The answer depends on whether you’re talking about a barnacle or a gull).  When are the best hiding places available?
4. What would happen if the tide stayed low all the time?   The animals and algae would dry out and die.  The shallow pools of water would eventually evaporate.  
5. What would happen if the tide stayed high all the time?   Gulls would have to find someplace else to look for food but large fish would be able to spend lots of time looking for food. Algae and plants would never dry out, and in fact may grow so well that species may start to compete for resources like food, access to sunlight, space on rocks, etc.     

Contrast Tidepools to Marsh and Dune habitats

Ambassador from each habitat describes differences.

Salt Marsh – wetland, peat, mosquito trenches, nursery, estuary, swallows, gulls

Dunes – dry, sandy, grasses hold sand, bird nests, holds back storms

Tidepools – rocky, tidal rack, tide pools, marine life

 

CLASSIFICATION – Living vs. Non-Living Tidepool Discoveries

Tidepools are teeming with life.  Some of the living creatures and algae may not look like they are alive (especially at low tide), but they are!  Discuss the difference between living and non-living tidepool finds.  How can you tell if something is alive?  Sort pictures/words into groups:

ADAPTATIONS - Camouflage

Many tidepool creatures are difficult to see at first, because they are so well camouflaged. Their coloration, shape, and/or texture may make them look like their environment. These adaptations help tidepool creatures hide from hungry predators who search the area during low or high tides.

Activity: Cryptic Crabs

1. Cut out 3 crabs from newsprint, 3 from three different colors of construction paper.  Affix all to newspaper, and cover before students enter.  Tell students they will have 20 seconds to count as many crabs as they can in this mock “tidepool”.  Unveil the creation for 20 seconds, and then recover.
2. Discuss how many crabs the children saw.  Then examine the mock tidepool closely.  Which crabs would be the last to be eaten, and why?  Many crabs are not only cryptic in their coloration;  some are shaped or textured like rock or sand.  Others decorate their shells with algae to further camouflage themselves.
3. Optional:  Add “rocks” to the tidepool, and hide some of the crabs under the rocks.

Follow-up Activity:

Pass out pictures of different marine organisms and have students describe what features help their animal camouflage/hide in its environment.

Post Visit

HABITAT – Compare substrates from marsh, dune and tidepool habitats

Bring small containers on your field trip to collect sand, dirt and rocks.  Make sure you label the containers so you know whether the contents came from the MARSH, DUNES or BEACH.  When you get back to school, examine your collections more carefully.

Activity:  Sand Cards

Fold a 3x5” index card in half, and cut a small wedge in the fold.  Unfolded, the card will have a small diamond-shaped hole in its center.  Cover the hole with clear cellophane tape, and place the card on a table, with the sticky part of the tape facing up through the hole.  Carefully sprinkle SMALL amounts of substrate onto the sticky tape.   Cover with another piece of tape.   Label the card with the date the sample was collected and where it was collected.  Use a microscope or magnifying glass to look at the sample under a bright light.  Record your observations.

Follow-up Activity:

Keep the sand cards in a file box and add to it throughout the year.  Encourage students to bring in soil samples from other places (backyard, beach vacations, etc.)

Questions:

What does the sample look like?

What sizes are the particles?

Are all the particles the same?

What are the particles made of?

Are there differences in the substrates in the marsh, dune and beach locations?

ADAPTATION – Holding On

Some animals are mobile, meaning they can move from one place to another.  Others are sessile, or stuck to something.  Some animals are mobile for some parts of their lives and sessile for other parts (for example, barnacle larvae move throughout the water column before settling on a substrate in an adult stage).

Activity:

Sort animals into groups based on whether or not they are mobile or sessile.  

Whether mobile or sessile, many tidepool animals and algae have mechanisms for “holding on”.   Why?  Discuss the turbulence of crashing waves and strong water currents sweeping back and forth.  HOW do these animals hold on? 

Activity:

Ask the children to fill in the blanks below for one organism they saw on their field trip.  Use pictures of tidepool organisms to help the children remember. 

I saw a: _______ and it held on to _______ by its ______________

Discuss different ways some tidepool animals and algae hold on.  For example:

Tidepool Activities -- Grades 3 to 5

Pre Visit Goals HABITAT  - Identify and appreciate the extreme changes constantly taking place in the tidepool environment:  High/low tide, wet/dry, cool/warm CLASSIFICATION - Mobile vs. Sessile animals ADAPTATION - Holding on, Staying Moist, Protection from Predators Visit Goals HABITAT – Identify characteristics of marsh, dune and tidepool CLASSIFICATION – Scavenger hunt helps group animals (Ex. “find three animals that have a shell”) ADAPTATION – Observe examples of camouflage, holding on, closing up, hiding, etc   Post Visit Goals HABITAT - Food Chain in a tidepool habitat CLASSIFICATION - Univalves/Bivalves, Mollusk/Crustacean/Echinoderm ADAPTATION -  Create your own tidepool creature

Pre Visit

HABITAT – Identify the characteristics of a tidepool habitat.  Appreciate the extreme environmental changes that take place as the tide goes in and out.

Activity:

Tidal fluctuations are a repeating pattern in nature.  Discover the similarities and differences in a given area during high tide and low tide. 

1. Give children a simple picture of a rocky shoreline.   Have children indicate the water level at the top.  What goes on under the water?  Barnacles extend their feather-like feet for feeding.  Mussels open slightly to feed.  Sea stars, periwinkles crabs, and fish move about under the water.  Large fish may be found.  Algae floats and sways with the water’s movement.  Birds fly overhead.  Affix appropriate cutouts to the appropriate areas on the picture and color. 
2. Give children a second picture identical to the first.   Now indicate a low water level, so that only the pools are filled with water.  Now where are the animals and algae?  How are they behaving?  Barnacles and mussels are closed up tight, still on their rocks.  Crabs hide under rocks.  Dry periwinkles hold on tight and stop moving.  Moving periwinkles, sea stars, and fish gather in the wet spots.  Algae sits limp and motionless.  Large fish have retreated to deeper waters.   Birds walk around, hunting for food.   Affix cutouts and color. 
3. Discuss the differences in these pictures.  Which situation is the most wet/dry?  The coolest/warmest?  Which is the best time to hunt for food?  (The answer depends on whether you’re talking about a barnacle or a gull).  When are the best hiding places available? 
4. What would happen if the tide stayed low all the time?   The animals and algae would dry out and die.  The shallow pools of water would eventually evaporate.  
5. What would happen if the tide stayed high all the time?  Gulls would have to find someplace else to look for food but large fish would be able to spend lots of time looking for food. Algae and plants would never dry out, and in fact may grow so well that species may start to compete for resources like food, access to sunlight, space on rocks, etc.     

CLASSIFICATION – Moving and Holding On

Some animals are mobile, meaning they can move from one place to another.  Others are sessile, or stuck to something.  Some animals are mobile for some parts of their lives and sessile for other parts (for example, barnacle larvae move throughout the water column before settling on a substrate in an adult stage).

Activity:

Sort animals into groups based on whether or not they are mobile or sessile.    Discuss how each animal moves or holds on.

 

Activity:

Pretend a new creature is coming to live in the tidepools.  Should it be mobile or sessile?   Divide the class into two (or multiples of two) and have one half become advocates for being MOBILE and the half other proponents of a SESSILE lifestyle.  Hold a mock debate, or have the new creature (a hand puppet?) interview the groups.  

What are some advantages to being mobile?  You can move in search of food, away from predators, away from competition, and away from problem environmental conditions.

What are some advantages to being sessile?  Less energy is spent on movement, and resources are spent on growth and reproduction.  Sessile tidepool organisms take advantage of the movement of the water around them… the water brings food, oxygen, and gametes from other animals.  Strong holding mechanisms help them avoid being swept away by the tide.  

 

ADAPTATIONS – Drying out

Life in a tidepool is marked by extreme changes in water level.  Tidepool creatures may be completely submerged at high tide, yet high and dry at low tide.  Discuss some of the adaptations tidepool animals have for keeping themselves moist and healthy during periods of low tides.

Closing up – Barnacles, mussels, and periwinkles are only a few of the animals that can tightly close their shells to the drying air.  Later, when submerged again, they can open their shells and feed.

Try this experiment:

Set up models of different tidepool animals.  Place wet paper towels inside a three plastic containers with lids.  Close the lid of the first container tightly.   Pop off the lid of the second container, and place it lightly over the top without sealing it.  Remove the lid entirely from the third container.  Place all three containers outside on a sunny day.  Check periodically to see what happens to the paper towels.  Which towels stayed damp?  Which dried out?  What do the paper towels and containers represent?

Hunkering down – Crabs hide in wet places under rocks.  They can be exposed to air for short periods of time as long as they stay moist.

Moving to the water – Sea stars, sea urchins, and crabs collect in tidepools during low tide.

Swimming away – Large fish swim to deeper waters. 

Post Visit

HABITAT – Web of Life

Use pictures of different tidepool organisms to play the Web of Life game.  Each child takes a picture of a tidepool organism, and the players sit or stand in a circle.  The first player holds the end of a long piece of yarn.  The first player, who may hold a picture of a sea star, identifies another player whose organism a sea star will eat or will be eaten by (for example, a sea star will eat a mussel).  The two players connect themselves using the yarn.  The second player (the mussel), finds another player holding something a mussel will eat or be eaten by, and the yarn ball gets passed along. Each player holds the yarn when the connection is made, and soon there is a tangled web of connections extending across the circle!

CLASSIFICATION – What’s in a name?

Scientists classify organisms into groups of organisms that are similar to one another.

One large group of animals often found in tidepools is called Mollusks.  These animals all lack backbones, have soft bodies, and many create shell homes.  There are two groups of mollusks with shells:

1. Univalves – Just as a unicycle has one wheel, and a unicorn has one horn, a univalve has one shell.  Uni means one!  
2. Bivalves – Bivalves have two shells, attached together at a hinge.  Think of other words where bi- means “two”.  Try bicycle, bicentennial, binoculars… 

Question:  If there were such a thing as a mollusk with three shells, what would you call it? 

Activity:

Write as many words as you can think of that have the words uni- meaning “one”, bi- meaning “two”, and tri- meaning three. 

ADAPTATION –  Creature Features

Invent a new tidepool creature, and draw its picture.  Explain how your creature will:

eat

drink

breathe

move (or not)

reproduce

protect itself from predators

avoid competition

withstand tidal fluctuations

Be creative!