Build a Model Tidepool Background The intertidal zone is the area of land between high and low tide. The intertidal is comprised of four distinct zones. Starting with the most inland zone, the spray zone is moistened by the splash of waves at high tide and is occasional submerged during extreme high tides or severe storms. Next, the high intertidal zone is dry most of the day and is only flooded during the peak of daily high tides. Then, the middle intertidal zone is where the daily tidal changes ebbs and flows. Finally, the low intertidal zone is almost always underwater except during the lowest tides of the year. As the tide recedes, saltwater is trapped in the low points along the shoreline, forming tidepools. These isolated pools can vary drastically in their size and depth and can be located in any of the intertidal zones.

The marine life that can be found living in tidepools is abundant, including barnacles, mussles, snails, crabs, algae, urchins, anemones, sea stars, cucumbers, small fish, and many more! The plants and animals that live in and around tidepools must be very hardy. During low tide these plants and animals are exposed to the harsh sun, strong wind, or near freezing temperatures (depending on the season), increasing water temperature, and increasing salinity.

The tides are influenced by the gravitational forces of the moon, sun and Earth, the Earth’s rotation, and the shape of the shoreline.

Materials Needed

 Dish pan or plastic bin  Lots of rocks and stones in various sizes  Mini sea creatures (You can make your own out of clay or use plastic toys)  Water  Pitcher or cup

Directions

1. Make mini sea creatures.

2. Fill your pan or bin with rocks. Arrange them so there are varying levels of rocks in your pan, creating a tide pool.

3. Place your mini sea creatures in the tide pool model.

4. Discuss which animals will be underwater first as water is added.

5. Add water one pitcher or cup at a time. (Pay attention to which animals are covered with water first.)

Continue adding water until you reach high tide. Notice how all the animals are underwater during high tide.

6. Discuss which animals will be exposed to the air first.

7. Remove water one pitcher at a time until you’ve reached low tide. Notice how at low tide most animals are exposed to air. (This is a great time to talk about any body parts, adaptations, or movements sea creatures have to help them with low tide!)

Explore Further Even more activities to inspire creativity and critical thinking for various ages.

1. Create waves in your tide pool. Talk about how waves and tides are different.

2. Place animals in the different intertidal zones. Talk about how different animals are adapted to live in different environments.

 Does the animal have a hard shell or soft body?  Is the animal stationary or can it move locations?  How can the animal keep from drying out during low tide?

3. If you live near the beach, go on a tide pool scavenger hunt.

4. Write a diary/journal entry about what a day in the life of your favorite tidepool animal would look like.

Literature Resources Check out the children’s books below to discover even more about sea life in tidepools!

In One Tidepool: Crabs, Snails, and Salty Tails by Anthony D. Fredericks

Information about tidepools: https://oceanservice.noaa.gov/facts/tide-pool.html

Information about the Intertidal habitat and its zones:

https://oceanservice.noaa.gov/facts/intertidal-zone.html

Information about tides: https://oceanservice.noaa.gov/facts/tides.html

Vocabulary Habitat- Environmental area where a particular animal normally lives.

High intertidal zone- Floods during the peaks of daily high tides but remains dry for long stretches between high tides.

Intertidal- The area where the ocean meets the land between high and low tides.

Invertebrate- An animal that does not have a spine, such as, a sea star, sea anemone, or clam,

Low intertidal zone-Virtually always underwater except during the lowest of tides.

Middle intertidal zone- over which the tides ebb and flow twice a day, and which is inhabited by a greater variety of both plants and animals.

Predator- an animal that lives by killing and eating other animals

Prey- an animal that is hunted or killed by another animal for food

Salinity- the amount of salt in a solution or liquid

Spray zone- Dampened by ocean spray and high waves and is submerged only during very high tides or severe storms.

Tide- The rise and fall of the ocean caused by the gravitational pull of the moon and the sun.

Tidepool- An isolated pocket of seawater found in the ocean’s intertidal zone

Vertebrate- An animal with a spine, such as a human, fish, seal, or whale,

Next Generation Science Standards Disciplinary Core Ideas Practices Crosscutting Concepts

 ESS3A: Natural  Developing and  Patterns Resources Using Models  Cause and Effect o K-ESS3-1  Constructing  Structure and  LS4C: Adaptations Explanations and Function o 3-LS4-3 Designing Solutions