One sea slug, (Elysia chlorotica), is green. Recently scientists investigated the color and found out that the sea slug makes its own food with chlorophyll! Chlorophyll, as you probably know, is the pigment plants use to make their food via photosynthesis. This sea slug not only borrows chloroplasts from the algae it eats, but also can make its own chlorophyll. It is the first animal to be shown to have that ability. Cool! ( Wired Science has a copy of the original article from ScienceNews. Both sites have ads, but the Wired site is less busy.)

Here’s a video that shows the sea slug eating algae. (The video is silent.)

This video from National Geographic shows other, more colorful sea slugs (nudibranchs). (You’ll have to close a pop-up ad.)

Why are these sea slugs so bright? The colors are to warn predators that they aren’t good to eat.

Activities:

1. Draw and color your own sea slug.View images of sea slugs by searching images online, or look for photos in books to help you. Research a particular sea slug. Find out where it lives, what its habitat is like and what it eats.

Tidepool Coloring Book has a drawing of a nudibranch you could use, as well as images of other tidepool creatures.

2. Writing Prompt:

Imagine what our world would be like if more animals could make their own food from sunlight. Imagine green cows or elephants. Now, write a story about it.

Related Activities:
Fieldwork has extensive lesson plans for a high school level marine biology/oceanography class. For example, here’s the lesson on Mollusca/beaches. The author recommends that you have access to a body of salt water to be able to do the hands on activities. Check out the “busy fieldworkers.” Now, that’s my idea of learning.

Tide Pool Invertebrates post from last summer

Thanks to Carl for the heads up about the green sea slug and Susan for leading me to the Fieldwork site.

Tracking Trash: Flotsam, Jetsam, and the Science of Ocean Motion (Scientists in the Field Series) by Loree Griffin Burns is about Dr. Curt Ebbesmeyer, an oceanographer who studies the huge streams of water flowing through the ocean, called currents. In 1990 his mother pointed out an article in the newspaper about piles of sneakers washing up on the shores near Seattle, Washington. Dr. Ebbesmeyer turned his scientific curiosity to the problem, and discovered the shoes came from containers that had fallen off a ship during a storm months before. The sneakers floated in the ocean currents and ended up washing up on shore. By tracking how fast and how far the sneakers moved, he and other scientists could map the direction and speed of the ocean currents carrying the sneakers.

Activities:

(Note: always watch children around water).

1. Bathtub or pool currents

Try to create a current in a bathtub or pool using a hose or a handheld shower head. Partially fill the pool or tub with water, then create a fast current by shooting water through it. Try adding a plastic floating toy to track the movement of the water flow.

2. Floating high versus low

Dr. Ebbesmeyer also studied the movement of some floating bathtub toys that had fallen off another boat. He found that the bathtub toys moved to shore more quickly than the movement of currents would have predicted. Then he floated a sneaker and a bathtub toy in seawater. What he saw suggested the answer.

Do you have an old sneaker or similar object that you could use to test this question? Float an old sneaker and a plastic bathtub toy in a tub or pool. Do they look the same in the water? Do they move through the water the same when pushed by currents?

Dr. Ebbesmeyer used seawater for his experiment. How do you think that might change the results?

His idea was that the bathtub toys floated high up out of the water and thus caught the winds. When the wind helps move an object along, it is called the object’s “windage.”

It turns out the plastic tub toys had been packaged in sets of four, yet none of the packages were washed up on shore. He wondered how the packages might influence the movement of the toys, so he placed packages of toys in tubs filled with seawater. He found the packages fell apart overnight, and so the toys were moving freely very quickly.

What else might change how an object moves in the water?

3. Plastic brick floating

In February of 1997 a ship lost containers filled with over four million LEGO pieces into the Atlantic Ocean.

Gather:

• Plastic bricks
• container for holding water, sink or bathtub

Now you are ready to answer some questions.

Do plastic bricks float?
Can you build a boat out of them?
Do you think they would float differently in seawater?

Check out the Techbrick Site for some photos of a LEGO boat race to give you ideas.

Tracking Trash: Flotsam, Jetsam, and the Science of Ocean Motion (Scientists in the Field Series) by Loree Griffin Burns

I admit, I wanted to be an oceanographer when I was in fourth grade. Now through this awesome book I can catch a glimpse of the world of oceanography.

For your information, the last two chapters are more about the trash found in the oceans, the giant pool of trash that is circulating in the Pacific Ocean, and how damaging adrift fishing nets can be. The information would be a tie-in to a study unit on environmental issues, as well.

Winter’s Tail is a new children’s book coming out in October. It is the heartrending story of a young dolphin named Winter who lost her tail after becoming entangled in a crab trap line.  After she healed, she was fitted with a prosthetic tail.

Scholastic and Turtle Pond Interactive have put together some activities to coincide with the book’s debut. You can see a short video introduction (Note: the video shows a mauled tail ), and find teaching materials at http://www.scholastic.com/winterstail/.

One of the events will be a webcast of a virtual field trip to the Clearwater Marine Aquarium in Clearwater Florida on Wednesday, October 7, from 1:00 p.m. to 1:45 p.m. (Eastern Standard Time).

Check out the science activities included in the educational materials.
There’s also an excerpt of the Winter’s Tail book.

Winter’s Tail: How One Little Dolphin Learned To Swim Again
by Juliana Hatkoff, Isabella Hatkoff and Craig Hatkoff

What kind of creatures are sea horses? Are they fish? They have an exterior that looks rather hard, so some people might wonder if they are crustaceans. The tiny fins and gills give it away though, sea horses are fish! If you replay the video, look for the tiny gills and fins moving.

Sea horses and their relatives, the pipefish and seadragons, are called gasterosteiform fish because they lack scales and have bony plates instead. They are poor swimmers and often rely on camouflage to hide from predators. The seadragons in particular have so many leafy flaps on their bodies they look like floating seaweed instead of animals.

Sea horses are carnivores and eat small crustaceans, such as tiny shrimp and planktonic invertebrates.

Activities:

1.Gyotaku and fish anatomy

Are you familiar with the Japanese art of gyotaku, making prints or rubbings from fish?

Traditionally, prints were made by applying paint to actual fish. Today you can also buy rubber or plastic replicas if you don’t have access to whole fish. You can print on paper or cloth as you choose. This particular fish is printed on cloth.

Gyotaku is great because it incorporates both art and science into a fun learning experience. While the children are looking at the fish they can learn fish anatomy (see resources below) and also details useful in identification of individual species. There are loads of places to learn more about gyotaku on the Internet, just load up your favorite search engine and go.

Try this gyotaku lesson plan at ArtsEdge for ideas.

Dick Blick art supplies has a model sea horse.

Acorn Naturalists also sells gyotaku supplies.

2. Moving Through the Water.

Different fish have different shaped bodies. Do some move through the water more easily than others?

(See fish body shapes .pdf in resources below) Edit: no longer available

Gather:

• modeling clay
• string or yarn
• scissors
• sink with water

Cut a few pieces of string about 18 inches long (at least two). Form a few golf ball-sized lumps, the same number as pieces of string. Take a small lump of clay and wrap around one end of the string, so the string is embedded. Form the lump into a rough sea horse shape. Now take another ball of clay and wrap around another piece of string. Form this into a typical fish shape, such as a trout. This shape is called fusiform. Put each shape into the sink and drag across the water. Does one shape move more easily than others? Try some other fish shapes as well. Which shape moves through the water most easily?

Resources:

Nova Program: Kingdom of the Seahorse Resources

National Geographic Seahorse

Tennessee Aquarium Seahorses

(Edit: broken links were removed.)

Now it is time to finish our summer beach science series and get ready for fall. We’ll miss the sand between our toes (although I think I still have some in my hair), but look forward to a brisk change of pace and some autumn foliage.

To check the rest of the posts on beach science, follow these links:

Shore Birds

Tide Pool Invertebrates

Beach Science- Boats

Beach Science Algae

Beach Science-Sand

Beach Science-Seawater

To continue beach science, let’s take a look at some other common visitors to the seashore. Grab an identification guide and some binoculars, and a camera if you want, and let’s investigate.

You may have seen sea gulls dozens of times, but have you really looked at one? Check out those pink webbed feet.

Investigation 1. How do the beaks and feet of shore birds differ from those of the song birds in your community? How are they similar? Ever seen a pelican at the beach?

Shore birds always seem busy.

Investigation 2. What do shore birds eat?

Investigation 3. Do shore birds drink? Where do they get their water?

Shore birds are often in big groups, like these cormorants.

Investigation 4. Why are shore birds often seen in flocks?

Investigation 5. Where do different types of shore birds nest?

(Hint for 4 and 5: think about bird movement or migration).

Now lie down on the beach, close your eyes and listen.

Investigation 6. What sounds do shore birds make?

Hope you have fun discovering shore birds.

Drop us a note in the comments and let us know what you find out.

Edit: To check the rest of the posts on beach science, follow these links:

Sea Horses and Other Fish

Tide Pool Invertebrates

Beach Science- Boats

Beach Science Algae

Beach Science-Sand

Beach Science-Seawater

Wow, what are all those weird creatures? Did you recognize the arms with the suckers? How about the purple spiny things?� Ever see a seashell scoot around like that? Tide pools are fascinating places to study science.

A majority of the animals you see in a tide pool are classed as invertebrates, which means they lack backbones. Invertebrates include animals like

jellyfish,

hermit crabs,

sea stars or starfish,

(Courtesy of Free Stock Photos for websites – FreeDigitalPhotos.net)

and

sea anemone.

(For more videos of tide pool creatures, try Marine Invertebrates Race Rocks.)

Activity: Today we are going to hone the observation skills needed to identify and classify the many diverse marine invertebrates by creating models.

First let’s get some inspiration by taking a look at models of marine invertebrates in the article More Than Art: The Blaschka Marine Invertebrates by William Warmus. Warmus tells the story of how when Thomas Eisner arrived Cornell University during the 1950s, he discovered a locked cabinet full of dusty sea creatures made of glass, and eventually traced their origins. Cool story with awesome photos!

Gather:

• Photos/drawings of various marine invertebrates such as the Invertebrate Guide at the Monterey Bay Aquarium
• Toothpicks, paint, markers, chenille, wikki stix (optional)
• Your favorite modeling compound such as:

- Salt dough
- Modeling clay
- We used: Crayola Model Magic (see below) with a coupon from the craft store

Study the examples and then create your own models. You can push in toothpicks as spines, and chenille or wikki skix as legs. Let the models dry and then paint and decorate them. You can use your models to create fun tidal pool scenes by adding rocks and/or construction paper algae.

Ideas:

If you have never tried it, Crayola Model Magic is a lot of fun. Look for sales and coupons. It is very easy to use and forgiving, so have fun and let your creativity loose!

If you are interested in downloading a poster of marine invertebrates, go to SPC Coastal Fisheries brochures and posters site and scroll down about half way to the “Marine Invertebrates of the Pacific Islands” poster.

I also recommend realistic aquatic invertebrate toys, especially is you live far from the beach. They are wonderful for bath play and can be used to build vocabulary. We used ours for sorting games too, a classification skill.

Books:
Children’s

A House for Hermit Crab by Eric Carle
Eric Carle’s beautiful illustrations make this book a perennial favorite.

How to Hide an Octopus and Other Sea Creatures by Ruth Heller
Ruth Heller is another favorite author of ours. This is a fun introduction to camouflage in the animal kingdom that teaches about a number of novel sea creatures.

What Lives in a Shell? (Let’s-Read-and-Find-Out Science 1) by Kathleen Weidner Zoehfeld and Helen K. Davie (Illustrator)

Simon & Schuster Children’s Guide to Sea Creatures by Jinny Johnson

There are a number of books about a single group of invertebrates, here are just two examples:

Sea Stars by Lola M. Schaefer

Crab by Lloyd G. Douglas

Adults might enjoy:

The Secret Life of Lobsters: How Fishermen and Scientists Are Unraveling the Mysteries of Our Favorite Crustacean (P.S.) by Trevor Corson

Edit: To check the rest of the posts on beach science, follow these links:

Sea Horses and Other Fish

Shore Birds

Beach Science- Boats

Beach Science Algae

Beach Science-Sand

Beach Science-Seawater

Boats!

Children are fascinated by boats and floating. You can do a lot of interesting science projects with boats, starting with some basic questions: How can huge pieces of heavy metal float? How are boats propelled? Can you really make a boat out of paper?

We already have covered some floating and boat topics in previous posts.

Why Things Float contains some experiments on floating and sinking.

The How long can a paper boat float? challenge, with the early results for paper boats challenge.
The yellow legal pad boats lasted five days.

The Bathtub Buoyancy Challenge asked kids to find ways to propel boats across a bathtub without using their hands or electrical motors. The Bathtub Buoyancy results show several ways to propel toy boats.

It is always fun to build bathtub-sized boats. This video shows two handmade boats powered by battery packs and small electric motors that my son invented recently. A modified toy car powers the paddle boat; the air boat fan is a modified toy airplane propeller.

Why don’t you try inventing a boat?

For more ideas, try

A Simple Steam Boat at Curious Cat

Miniature Boats at HowStuffWorks

Hope you have fun and let us know what kind of boat you invent!

Edit: To check the rest of the posts on beach science, follow these links:

Sea Horses and Other Fish

Shore Birds

Tide Pool Invertebrates

Beach Science Algae

Beach Science-Sand

Beach Science-Seawater

Have you ever found something plant-like on the beach and wondered what it was?

Seems like a lot of beach plants are hard to classify. Are they algae, a sort of seaweed, or are algae and seaweed the same thing? Are algae plants or do they belong to a different kingdom? These are all good questions, and scientists are just beginning to answer some of them.

Many of the plants and plant-like creatures you see at the beach are technically algae. For example, kelp are giant brown algae.

Algae come in many colors, like these red ones.

The green algae are often found in freshwater ponds and lakes.

Ready to learn more? Here are some suggestions for activities to investigate algae. I’d love to hear your ideas, as well.

Activity 1. Make an algal collection

Gather algae on the beach and keep it moist in seawater. If you have never worked with algae, the Hawaii Botany Department tells you how to make an algal herbarium. Or if you don’t want to disturb nature, you can take close up photographs of what you find.

Once you have a collection, visit these websites to help you identify what you have.

Michael Guiry’s Seaweed Site covers all things seaweed and the identification of algae.

Life on the Australian Shores and Algae: The Forgotten Treasure of Tidepools are also helpful, although the later tends to get a bit silly at times.

You may be wondering why anyone would care about algae. Turns out, algae are important in a lot of ways.

Activity 2. Investigate food chains.

Algae are the basis for aquatic food chains in both seawater and freshwater.

If you are unfamiliar with the concept of food chains, this book is a great introduction to food chains and food webs. It has been a family favorite.

Who Eats What? Food Chains and Food Webs (Let’s-Read-and-Find-Out Science, Stage 2) by Patricia Lauber and Holly Keller (Illustrator)

Find out as much as you can about food chains in the oceans. Gather, print and cut out pictures of ocean critters to illustrate your own posters of food chains or webs.

Activity 3. People eat algae too.

You have probably eaten algae and didn’t even know it. Carrageenan, a thickener used in a variety of foods, is extracted from a red alga. For more information, see http://encarta.msn.com/encyclopedia_761573848_3/algae.html.

Once you have an idea what to look for, head to your kitchen and check to see if you have any foods that contain carrageenan or other products made from algae. Look at the cookbook listed below (or a similar one), and make some of your own dishes using algae. Asian markets are often an excellent source of ingredients.

If you are interested, a fun research project would be to investigate all the ways people use algae for food throughout the world.

Activity 4. Other important uses for algae.

See if you can make a list of other uses for algae. Here are some I found:

Algae are thought to make much of the oxygen we breathe.

This video shows a camera zooming in on the leaves and then the cells of a common water plant, Elodea. In the cells you can see the chloroplasts moving around. The chloroplasts are the sites of photosynthesis, the process that turns sunlight into chemical energy we can use as food. A by-product of photosynthesis is the release of oxygen. Although Elodea is actually a vascular plant, the process in green algae is the same.

If providing food and oxygen weren’t enough, now scientists have discovered ways to use the oils found in algae to make biodiesel. In fact, algal oils can be made into jet fuel. See this previous post for more information about algal research at ASU.

If you are interested in algae, here are a few books you might want to try:

The Seaweed Book: How to Find and Have Fun With Seaweed (Paperback) by Rose Treat and Randy Duchaine (Illustrator, Photographer)

For Adults:
Seaweeds of the Pacific Coast: Common Marine Algae from Alaska to Baja California by Jennifer Mondragon and Jeff Mondragon

The New Seaweed Cookbook: A Complete Guide to Discovering the Deep Flavors of the Sea by Crystal June Maderia, Josephine K. Spilka (Foreword)

Have fun with some seaweed science and let me know what you discover!

Edit: To check the rest of the posts on beach science, follow these links:

Sea Horses and Other Fish

Shore Birds

Tide Pool Invertebrates

Beach Science- Boats

Beach Science-Sand

Beach Science-Seawater

Today we are going to continue our series on beach science by looking at sand. Although not all beaches are sandy, if you are lucky enough to visit one you can do some interesting science activities and experiments.

1.    Where does sand come from?

Find a tough metal or heavy plastic container with a tight-fitting lid. Add some relatively clean pebbles inside (a mix of different kinds works best). Close the lid tightly and let the kids shake it for as long as they want. Even after a few minutes, if you pour the pebbles onto a white piece of paper you will begin to see chips of rock that have broken off.

Or if your child has some rocks in a rock collection that have been jumbled together, you will often see “sand” starting to build up in the bottom on the container. When rocks bang against rocks they break apart.

Now think about where rocks might tumble against each other in nature. Where might sand form?

2.    Sand grains “from an ant’s eye view.”

One of our favorite exhibits at the local Arizona Mining and Mineral Museum shows different types of sand from “an ant’s eye view,” that is magnified so the grains look like boulders. When you pack for the beach, consider taking a sturdy magnifying glass to explore the sand up close (and any creatures you might encounter).

If you don’t have a magnifying glass or microscope to study sand grains, check out
A Grain of Sand Picture Gallery. Wow! These pictures are from a book of the same title listed in the books for adults and older children below.

On the same topic, see Sand Grains: Chips Off The Old Rock

3.    Sand Magnetism

Quite by accident we discovered that if you roll a magnet through sand, you can pick up bits of particles that contain iron. Note: it is really hard to get the iron bits off again. Put your magnet in a plastic sandwich baggie and it will make clean up much easier. You’ll be amazed at what your children will pull out of the sand.

4.    Sand and Water

Sand and water play is so important for children, even older ones. All you need are a few buckets, old plastic tubs and maybe some shovels and you have the recipe for some serious study.

Hey, there’s water down there.

Future physicist?

Sand physics links for older children:

The Physics of Sandcastles

Compression of Sand

Some relevant books:

Sand (Jump Into Science) by Ellen Prager

Ribbons of Sand: Exploring Atlantic Beaches by Larry Points and Andrea Jauck

Adults and Older Children

A Grain of Sand: Nature’s Secret Wonder by Gary Greenberg

Sand: The Never-Ending Story by Michael Welland

Edit: To check the rest of the posts on beach science, follow these links:

Sea Horses and Other Fish

Shore Birds

Tide Pool Invertebrates

Beach Science- Boats

Beach Science Algae

Beach Science-Seawater

What do you usually see at the beach? Of course you’ll see sand, rocks and water. If you are lucky you may also spot some wildlife and algae. Over the next few weeks we are going to have a series of science discussions, experiments and activities on things you find at the seashore.

This week:  Seawater Science

It doesn’t take long at the beach to discover that seawater is salty. You can taste the spray on your lips. Ever wondered why seawater is salty or what is in it that makes it taste salty? There really is science in seawater.

1. Seawater pH

One easy experiment is to take along some pH paper and check how acid or basic seawater is. Compare it to other substances and to tap water.

Typically seawater is basic, that is higher than 7.0. Seawater pH is an important aspect of its chemistry because it impacts such processes as the laying down of calcium by corals.

2. Seawater salts

Gather:

• Seawater
• Plain water
• 2 similar stainless steel or glass pans, or better yet, beakers
• Heat source like a stove
• Potholders

With the help of an adult, bring one cup of seawater in one pan and one cup of tap water in another pan to a boil. Turn down the heat and simmer until the water is almost dry. Watch carefully. Try not to let it boil completely dry because that will harm the metal of the pan. Remove from the heat and set in a warm place to finish evaporating away the water. What’s left?

Optional:  in a third pan place tap water and add a Tablespoon of salt. Boil as above. What happens when you evaporate the water in this case?

You should see a residue in the seawater pan. Pretend you are a chemist. How would you figure out what is in the residue?

One way is to do a flame test. When different chemicals are added to a flame, the resulting colors can give you information about what salts or elements are present. Here a trained chemistry teacher shows how this works.

Note: If you’d like to see how to do this, the book Fireworks by Vicki Cobb and Michael Gold (Photographer) has instructions for performing flame tests included as one of the activities. See Fireworks for the Fourth of July for a review.)

Using flame tests and other techniques, scientists have found over 70 elements in seawater.

How did those elements get into seawater? When I was young, I learned that the movement of freshwater over the earth’s crust picked up salts and carried them into the sea. Over time the salts built up because they are left behind when the water evaporates to move through the water cycle.

When I watched Going Deep on Scientific American Frontiers I found out that isn’t the only way salt gets in the ocean.

About thirty years ago, deep sea explorers found features known as hydrothermal vents along mid-ocean rifts. These are places on the ocean floor where seawater seeps into cracks in the crust. The water becomes extremely hot when it comes into contact with magma under the surface. It can’t boil, however, because of the extreme pressure at those depths. It dissolves some of the minerals from the crust and then flows back up into the ocean, carrying the dissolved minerals with it. Scientists have figured out that these vents are a significant source of the salts in the ocean.

A final process that provides salts to the oceans is the eruption of volcanoes under water. This is similar to the vents because the seawater is reacting with hot magma and lava, and dissolving some of the minerals in the liquid rocks.

Seawater is fascinating stuff and we still have a lot to learn about it.

Hope you have fun at the beach and watch out for those waves!

Resources:

For the youngest set:

Hello Ocean by Pam Munoz Ryan and Mark Astrella (Illustrator)

For older kids:

The Magic School Bus on the Ocean Floor by Joanna Cole and Bruce Degen (Illustrator)

Blue Planet: Seas of Life DVD

Note: the linked page has some video clips.

For Adults:

A Scientist at the Seashore (Dover Science Books) by James S. Trefil

Smithsonian Ocean: Our Water, Our World (Hardcover) by Deborah Cramer

Edit: To check the rest of the posts on beach science, follow these links:

Sea Horses and Other Fish

Shore Birds

Tide Pool Invertebrates

Beach Science- Boats

Beach Science Algae

Beach Science-Sand