Fiddler Crabs

Mrs. Gridley, Grade 4 Pfaff Elementary School

What Do You Think About Fiddlers?Where do they live? Do you think their habitat has salt

or fresh water? Do they like warm or cold climates?

What might they eat? Do they eat meat, plants, or both? (carnivore, herbivore, or omnivore)

Who is an enemy of the Fiddler? How can they protect themselves?

What are some special adaptations of the Fiddler? (something special it can do, or a special feature on its body)

BASIC NEEDSCan you name the FIVE basic needs of ALL

living things?

F - - -W - - - -A - -S - - - - (room to grow)S - - - - - - (safety, cover from bad weather)

HABITAT Your habitat is where you find all of your basic needs. The Fiddler’s habitat is…

a salt marsh! Muddy, grassy, flat area- between low and high tides

They love to burrow and can go about two feet deep.

Look for little mud balls known as “plugs” which close up the Fiddlers’ burrows. (The crabs take nutrients from the mud with their mouths, and they use what’s left to make the mud balls!)

Think about an ocean you’ve visited. Describe where the marsh is located, and what you find in a marsh. What types of plants and animals live in a marsh?

Check out the Fiddler’s Home!

These places have sand, salt water, grasses, mud, some rocks, and low and high tides. The Fiddlers like to burrow in a flat, murky area. They only need about a square foot of space to make their home.

APPEARANCEThe male Fiddler has a large claw shaped like a “fiddle”

that can be two inches long. What do you think the large claw is used for?

Four pairs of walking legs- Can you describe how a crab moves?

Crustaceans- what does this mean? The shell is called a “carapace” and is square-shaped, about one inch across.

Cold blooded- how is that different than having warm blood? What temperature is a human’s blood?

Changes colors when the temperature changes- range of colors from tan, brown, pinkish, purple, and even turquoise

ADAPTATIONSAnimals (even humans!) have special things they can do

(behaviors), or special features on their bodies, to help them survive.

For example, a dog has excellent night vision. A cat can flip itself in the air so it lands on its paws (most of the time). Hawks have sharp talons to grab their prey.

The Fiddler has many adaptations such as: eye stalks, gills (for holding in water), one large claw (males), and more!

Discuss how these adaptations might help the crab survive.The Fiddler can absorb oxygen from the environment around

them if they keep their gills moist. They can stay on land for months if needed! That is one awesome adaptation!

DIETA Fiddler Crab is…an omnivore.

The Fiddler eats something called:P - - - - - - -

The Fiddlers eat tiny bits of plants and animals that a human eye can hardly see. Their food floats or swims in the water. These crabs like to eat in puddles and will scrape the food into their mouth.

Look for their sharp teeth!

Predators…and How to Survive Against ThemWhich of these animals do you think are the

Fiddler’s predators? How can the Fiddler protect itself or hide

from their enemies?

Fascinating Fiddler FactsThe female Fiddler carries her eggs for two weeks

and then releases them into the water (in nature).Adult fiddlers molt twice a year in nature- what does

this mean? What other animals molt?The male’s large claw will grow back if it is lost!A female has an easier time getting food. Why?Very active during the day (in nature)The Marsh Fiddler is the smallest type of Fiddler

found in the Chesapeake Bay in Maryland.Some people say these crabs look like spiders.About 100 species living in various parts of the world

Male, Female, or Can’t Tell?

Think About It…For each scenario, decide if the Fiddler would

move to a new location, adapt (adjust), or die.

The water in the marsh is becoming polluted by people’s trash and oil from boats.

Many new homes are being built in the area, and some of the marshes are being filled in with land.

There is a bad bacteria that has killed off a lot of the marsh grass.

The climate has changed and has become much colder. Many of the Herons have flown off to warmer locations.