Our family finally made it to the beach and had a lot of fun. We visited the Monterey Bay Aquarium and saw the “Secret Life of Sea Horses” exhibit. It was awesome, take a peek (the aquarium was packed, so excuse the noise):

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.

This pretty silly video from National geographic gives more fun facts.

Activities:

1. Gyotaku and fish anatomy

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

gyotaku

Traditionally, prints were made by applying paint to actual fish. Today you can buy rubber or plastic replicas, including those for sea horses. You can print on paper or cloth as you choose. This particular fish is printed on cloth.

Our instructions for making gyotaku (previous post).

2. Moving Through the Water.

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

Check the CDAS website or the Catalina Island Marine institute for an introduction to fish body types.

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 (perpendicular to string).

Now take another ball of clay and wrap around another piece of string. Form this into a typical fish “tube” shape wrapping around the string.

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?

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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.

ocean

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