Crawfish 101
Teacher Instructions
Overview:
The focus of this lesson is learning more about common Louisiana
crawfish biology (i.e., body parts, species types/numbers, molting,
exoskeleton strength and purpose, etc.) by observing a live
specimen and making a simulated exoskeleton.
Grade Levels:
Upper elementary
Learning Objectives:
The students will:
 Observe live crawfish specimens to identify the major
external parts of the crawfish.
 Recognize the functions of the major external parts by
watching crawfish walk, react to stimuli and swim.
 Simulate the molting process.
 Describe the process and purpose of molting.
Duration:
Three class periods
Materials List:
 12-inch (30-centimeter) round balloons
 Antibacterial hand wipes (teacher provides)
 Clothespins
 Distilled water (teacher provides)
 Disinfectant wipes (teacher provides)
 Hot dog meat / wiener (teacher provides)
 Ice chest (teacher provides)
 Large bowl (teacher provides)
 Live crawfish (available from March through May) (teacher
provides)
 Mass scale (teacher provides)
 Newspaper (teacher provides)
 Paper towels (teacher provides)
 Rulers
 Salt (teacher provides)
 Shoebox size plastic containers (teacher provides)
 Small bowls (teacher provides)
 Toothpicks
Subject Area:
Science
Setting:
Classroom
Vocabulary:
Abdomen
Arthropod
Carapace
Cephalothorax
Chelipeds
(kee-luh-peds)
Crustaceans
Decapod
Exoskeleton
Invertebrate
Omnivore
Grade Level Expectations:
Third Grade
1. Ask questions about objects and events in the environment (e.g., plants, rocks, storms) (SILSU AgCenter • 4-H Youth Wetlands Program • 2015 • Upper Elementary • Crawfish 101
E-A1)
6. Use the five senses to describe observations (SI-E-A3)
8. Select and use developmentally appropriate equipment and tools (e.g., magnifying lenses,
microscopes, graduated cylinders) and units of measurement to observe and collect data (SI-EA4)
12. Identify and use appropriate safety procedures and equipment when conducting
investigations (e.g., gloves, goggles, hair ties) (SI-E-A7)
35. Compare structures (parts of the body) in a variety of animals (e.g., fish, mammals,
reptiles, amphibians, birds, insects) (LS-E-A3)
57. Describe the interrelationships of living (biotic) and nonliving (abiotic) components within
various ecosystems (e.g., terrarium, swamp, backyard) (SE-E-A1)
Fourth Grade
1. Ask questions about objects and events in the environment (e.g., plants, rocks, storms) (SIE-A1)
7. Use the five senses to describe observations (SI-E-A3)
9. Select and use developmentally appropriate equipment and tools (e.g., magnifying lenses,
microscopes, graduated cylinders) and units of measurement to observe and collect data (SI-EA4)
12. Use a variety of appropriate formats to describe procedures and to express ideas about
demonstrations or experiments (e.g., drawings, journals, reports, presentations, exhibitions,
portfolios) (SI-E-A6)
13. Identify and use appropriate safety procedures and equipment when conducting
investigations (e.g., gloves, goggles, hair ties) (SI-E-A7)
41. Describe how parts of animals’ bodies are related to their functions and survival (e.g.,
wings for flying, webbed feet for swimming, etc.) (LS-E-A3)
53. Identify the habitat in which selected organisms would most likely live and explain how
specific structures help organisms to survive (LS-E-C2)
Fifth Grade
6. Select and use appropriate equipment, technology, tools and metric system units of
measurement to make observations (SI-M-A3)
7. Record observations using methods that complement investigations (e.g., journals, tables,
charts) (SI-M-A3)
23. Use relevant safety procedures and equipment to conduct scientific investigations (SI-M-A8)
23. Provide appropriate care and use safe practices and ethical treatment when animals are
involved in scientific field and laboratory research (SI-M-A8)
34. Recognize the importance of communication among scientists about investigations in progress
and the work of others (SI-M-B5)
27. Compare common traits of organisms within major ecosystems (LS-M-C3)
Common Core State Standards:
Third Grade
3-LS4-3. Construct an argument with evidence that in a particular habitat some organisms can
survive well, some survive less well, and some cannot survive at all. [Clarification
LSU AgCenter • 4-H Youth Wetlands Program • 2015 • Upper Elementary • Crawfish 101
Statement: Examples of evidence could include needs and characteristics of the organisms
and habitats involved. The organisms and their habitat make up a system in which the parts
depend on each other.]
Fourth Grade
4-LS1-1. Construct an argument that plants and animals have internal and external structures that
function to support survival, growth, behavior, and reproduction. [Clarification Statement:
Examples of structures could include thorns, stems, roots, colored petals, heart, stomach,
lung, brain, and skin.] [Assessment Boundary: Assessment is limited to macroscopic
structures within plant and animal systems.]
Vocabulary Definitions:
Abdomen – The back part of a crawfish’s body.
Arthropod – Member of the phylum Arthropoda; invertebrate animal with an exoskeleton, a
segmented body and jointed appendages.
Carapace – The thicker part of a crustacean’s exoskeleton that covers the top and sides of its head and
thorax (cephalothorax).
Cephalothorax – The front part of a crawfish’s body that is made up of its head and thorax.
Chelipeds (kee-luh-peds) – The front two legs of a crawfish, which have large claws at the ends.
Crustaceans – Animals with a hard outer shell, such as crawfish, lobsters, crabs and shrimp (a
subgroup of invertebrates).
Decapod – An order of crustaceans that have 10 feet (legs).
Exoskeleton – A crawfish’s hard outer shell.
Invertebrate – Animal that does not have bones or a backbone.
Omnivore – An animal that eats both plant and animal material.
Background Information:
Crawfish are known by many names to Louisianans: crawfish, crayfish, crawdad and mudbug.
This crustacean is similar to a lobster, but much smaller, ranging from 3 to 10 inches as an adult
depending on the species and where it lives. Baby crawfish are about the size of a mosquito.
There are approximately 500 species of crawfish in the world. More than 350 of these species
reside in the streams and rivers of the United States, and 65 of those species are classified as
endangered. More specifically, Louisiana is home to 36 different species of crawfish. Two of those
species, the white river crawfish and the red swamp crawfish, are grown and distributed for human
consumption. You can tell them apart because the red swamp crawfish has heavy and thick pincers.
In contrast, the white crawfish has at least one long and one slender pincher. Red crawfish frequent
LSU AgCenter • 4-H Youth Wetlands Program • 2015 • Upper Elementary • Crawfish 101
swamps, bayous and ditches, and white crawfish can be found in larger bodies of water that are
deeper, such as lakes.
Most crawfish live in fresh water and live to be 2 to 3 years old. They are mostly nocturnal
and prefer cooler temperatures and a wet environment. If crawfish are out during the day, they often
hide under rocks or logs. Their pincers, head and antennae face outside, so they can sense if danger is
approaching and initiate protective measures.
Observing a live crawfish helps students see how it can be classified as an arthropod and
view how its outer parts help the crawfish function. Students probably have had experiences eating
the crustaceans in one form or another, but providing this opportunity to get an “up close” and
focused look at an important part of Louisiana’s culture is beneficial to understanding how a crawfish
interacts in Louisiana’s wetlands.
Crawfish Anatomy
As crustaceans, crawfish have a hard outer exoskeleton that surrounds their bodies. The
exoskeleton is made of calcium and chitin, which make it thin and flexible but also strong enough to
protect their internal tissue. Crawfish outgrow their exoskeleton and go through the molting process
about 11 times during their lifetime. This happens when the shell splits between the carapace and the
abdomen. A crawfish eventually exits its old shell by flipping its tail repeatedly. After molting,
crawfish remain without a shell for about 12 hours. The crawfish’s exoskeleton is still very soft,
which makes them vulnerable. When crawfish have reached their full size, they no longer molt.
The body of a crawfish is divided into three sections: the head, thorax and abdomen. On a
crawfish, the head and thorax are fused together, termed the cephalothorax. The carapace is the
thicker part of a crustacean’s exoskeleton that protects the top and sides of its cephalothorax.
Crawfish have eyes on top of stalks that stick out of the top of their heads. They can see very
well on land because they have compound eyes, like flies, which basically means their eyes are made
up of many small eyes. They can move their eyes all around, too. Their excellent vision helps them to
see danger right away when they are on land. Interestingly, crawfish can regenerate an eye if it gets
hurt or lost.
To breathe, crawfish have gills, like fish, to take oxygen from the water through their
exoskeleton. The gills are located under the carapace. Crawfish also use their gills to get oxygen from
the air, but the gills must be moist for this to work.
Since crawfish like water, nighttime temperatures and mud, they may not be able to see as
well in the dark, murky waters. So they use their antennae to sense things around them. Antennae
aren’t hair. Instead, the antennae are a sensory organ that contains small hairs that help crawfish
sense things by feeling and “smelling” around them. To accomplish this, a crawfish has four
antennae, two small and two long, on its head. A crawfish can regenerate its antennae, if needed.
A crawfish’s two claws, also called cheliped (pronounced kee-luh-ped), are used to grab, hold
and tear food. Chelipeds are considered to be legs. The claws also are used as a defense mechanism,
during the mating process, to build a crawfish’s home and as an aggressive display where crawfish
wave claws around, opening and shutting them in the air to scare off enemies.
There are four pairs of walking legs that are used to move forward, backward and sideways.
With the two chelipeds included, the crawfish has 10 total legs. This is why it is known as a decapod
(deca = 10, pod = foot). Walking legs are jointed and are attached to the cephalothorax. If a crawfish
loses a leg, it can regenerate another one.
The abdomen ends in a tail fan, which is jointed and can be curled under itself very quickly.
This helps the crawfish shoot backward very quickly in the water, making it hard to catch. The tail
LSU AgCenter • 4-H Youth Wetlands Program • 2015 • Upper Elementary • Crawfish 101
also can be used as a swimming aid. Ten pairs of swimmerets are located below the crawfish’s
abdomen. These swimmerets may look like small legs, but their name hints to their use as a
swimming aid.
Advance Preparation:
1. Visit library to get informational books about crawfish (Some excellent books are cited in the
resource section of this lesson.), encyclopedias, invertebrate or crustacean books with pictures
and descriptions of crawfish and “Why the Crawfish Live in the Mud” book.
2. Purchase 1-3 pounds of live crawfish the day before the lesson is to be implemented. See the
Lesson Safety and Tips section of this lesson (below) for directions on how to keep them alive
and how to handle them.
3. Make copies of all student activity sheets. (See blackline masters.)
a. Crawfish Parts and Functions (1 per pair of students)
b. Crawfish Parts and Functions KEY (1 for teacher)
c. Vocabulary (1 for teacher)
d. Live Crawfish Exploration (1 per pair of students)
e. Crawfish Comparison Chart (1 per pair of students)
f. Crawfish Comparison Chart KEY (1 for teacher)
g. Crawfish Quiz (1 per student)
h. Crawfish Quiz KEY (1 for teacher)
4. Cut out the Vocabulary Cards. (See blackline master.)
5. Make the papier-mache mixture just prior to the class period on Day 2 of the procedure.
a. Papier-mache paste recipe:
3/4 white glue to 1/4 water (If using a thick glue, go 1/2 and ½.)
Lesson Safety and Tips:
Maintaining live crawfish overnight and the next day
1. 1. Put crawfish in a container with a quarter-inch of distilled water. The water should only be
high enough to keep their undersides wet.
2. Cut holes in the lid of the container for air.
3. The crawfish can remain alive for weeks if the distilled water is changed regularly and they
are fed every few days.
4. Note: Do not release the crawfish into the environment after the activity. Instead, bring them
back home and boil them for dinner or give them to someone who can.
Crawfish Safety Tips
1. Have students wash hands before and after this exploration.
2. Pick up crawfish by placing the carapace (just above the walking legs) between the thumb and
forefinger. Demonstrate this for students before you allow them to interact with the live
crawfish.
3. You can ask the seafood vendor to bind at least one claw for you. That way students can at
least view how one pincher works.
LSU AgCenter • 4-H Youth Wetlands Program • 2015 • Upper Elementary • Crawfish 101
4. Even though crawfish have a hard exoskeleton, they also can be extremely delicate. Handle
live crawfish with care.
5. Place the crawfish down in the bowl and on the table. Be careful not to drop them because a
short fall can injure or even kill a crawfish.
6. Use only distilled water.
7. Do not keep the crawfish out of the water longer than 5 to 10 minutes.
8. Do not splash the water.
9. Do not pick up the container of water. Leave it on a flat surface.
10. Do not force or tease anyone who may be scared of touching the crawfish.
11. Only pick up a crawfish to place it where the exploration tells you. Do not pick up the
crawfish and put it on someone or near someone’s face or hands.
12. When working with crawfish, make sure students keep their hands away from their faces.
Papier-mache
1. If the humidity is high, add less water (up to 1/4 less) to your papier-mache mixture.
2. Cover your project with no more than four layers of papier-mache. Two layers is a good
amount for kids because they will probably overlap more than they should.
3. When allowing the papier-mache to dry, keep in a dry, well ventilated and well lit place.
Otherwise, mold may grow.
4. Add salt to the recipe to prevent mold.
5. Let the papier-mache dry completely.
6. Look for the So Cool Science website: Insects Shedding Exoskeleton and Papier-mache
Balloon Experiment in the reference section of this lesson. It models insect molting, but it also
is helpful for the crawfish molting process. View the video ahead of time to make sure you
guide students correctly through the balloon molting process.
Procedure:
Guiding Questions
 How does an exoskeleton protect a crawfish?
 What are the different purposes for those parts of a crawfish?
 Where does a crawfish live?
 How is the crawfish burrow made and what is it made of?
 How is a burrow important to a crawfish?
Day 1: Crawfish Exploration
Note: Make sure to get through steps 1-9 in 10 minutes to have time for the activity.
1. Familiarize yourself with crawfish by reading the background section and the safety and tip
section of this lesson. Very important information is located in both of these places, and it
must be adhered to for a safe and successful live crawfish observation.
2. Students should work in pairs for this activity.
3. Pass out the Crawfish Parts and Functions work sheet to each pair of students.
LSU AgCenter • 4-H Youth Wetlands Program • 2015 • Upper Elementary • Crawfish 101
4. Ask them to look at the prediction chart carefully to see if they can name the parts that are
being identified by the arrows. Make sure they are not writing on the sheet yet. Give them
about two minutes.
5. Have them stop and look at you. One at a time, hold up the Vocabulary Cards for the parts of
the crawfish. Have students quietly point to (not write) where they think each part is. (This
process will work best, because through process of elimination; they will be able to make a
better identification.)
6. Next, display all the vocabulary cards where students can see them, such as on a chalkboard
tray or taped on the wall.
7. Discuss with the students where they decided the parts were located. Use the Crawfish Parts
and Functions KEY to make sure students have identified the part names correctly.
8. Give the students three to five minutes to predict the function of each part. They will fill in the
actual function after the activity.
9. Tell them to set the Crawfish Parts and Functions work sheet to the side for now. They will
use it as a resource during the exploration.
10. Pass out the Live Crawfish Exploration work sheet to each pair of students.
11. Read the Crawfish Safety Tips (included earlier in this lesson) to the students.
12. Tell the students they will be observing live crawfish today to explore crawfish anatomy and
behavior. Tell them they must maintain respect for the live creature during this opportunity.
a. Make sure they do not horseplay with or hurt the crawfish in any way.
b. Make sure they demonstrate care and respect for the crawfish.
13. Pass out all the materials needed for the exploration (rulers, scales, one crawfish per clear
container with water that just covers the crawfish but not submerges it and paper towels for
water cleanup or to dry hands after handling the crawfish).
14. Allow the students 30 minutes to complete this activity.
15. Regularly squirt or pour distilled water on the crawfish to keep them hydrated.
16. Walk around the classroom and closely observe the students. If you stop to talk or question
pairs of students, make sure you stand so you can still watch the rest of the class. This will
help maintain the safety of the class and the crawfish.
17. Make sure students remain on task and strictly follow the safety and tips you reviewed.
18. When time is up and students have completed the observation, make sure to have students
clean up their areas and put the supplies back where they belong. Put live crawfish back in ice
chest.
19. Have students clean their areas with a disinfectant wipe and then wash their hands thoroughly.
20. As students return to the classroom, have students look back at the predictions they made on
the Crawfish Parts and Functions and discuss what they have learned with their partners
before a class discussion occurs.
21. As a class, have students discuss thoughts about what the actual function of each labeled part
is. Review the answers (KEY) with the students to make sure they have the correct answers.
Give them time to write the correct answers on their sheets.
LSU AgCenter • 4-H Youth Wetlands Program • 2015 • Upper Elementary • Crawfish 101
Day 2: Exoskeleton Preparation and Comparison Chart
1. Prepare papier-mache paste just prior to the class period (see Advance Preparation section).
2. Pass out a balloon, newspaper strips, a small bowl with papier-mache paste and a clothespin
to each pair of students.
3. Leave enough supplies for you to make a teacher model.
4. Show each of the following steps and allow the students to perform each step after you
demonstrate it.
a. Blow up the balloon to about the size of a grapefruit. Have students complete the task.
b. Twist the end of the balloon closed, but do not tie it. Instead, secure the twisted end
with the clothespin. Have students complete the task.
c. Dip a newspaper strip in the paste mixture and stick the strip on the balloon. Repeat
this with a second paper strip, placing it on the balloon so it overlaps half of the first
strip. Have students complete the task.
d. Explain that you will continue adding strips, overlapping each one until most of the
balloon is covered with paper. Try to only put two layers of strips. Make sure to leave
an opening around the end of the balloon (clothespin side). Have students complete
the task.
5. Leave overnight to dry. (See safety and tips section of this lesson to help with this task.)
6. Pass out the Crawfish Comparison Chart for students to complete individually.
7. Read the directions with the students and review the crab example that’s included.
8. Give students about 10 minutes to complete this task.
Day 3: Molting Exoskeleton (Papier-mache)
1. Make sure the paper from yesterday’s papier-mache project is completely dry. A firm paper
shell will cover the balloon.
2. Discuss with the students how the firm shell represents the exoskeleton of the crawfish and
the balloon represents the soft body of the crawfish. Refer back to the background
information.
3. Remove the clothespin but don’t let the air out of the balloon.
4. Gently blow into the balloon, making it slightly larger.
a. Ask the students what they think will happen? (When you blow up the balloon, the
uncovered section of the paper shell separates slightly.)
b. Ask the students why they think this happens. (The balloon and hard paper shell
represent an arthropod such as the crawfish. Its body is covered by an exoskeleton
because it is an invertebrate – without a backbone. This exoskeleton does not grow
with the crawfish. As the rest of its body grows, the exoskeleton becomes too small. A
new exoskeleton begins to form under the old one.)
c. Explain that when the old exoskeleton becomes too small for the growing crawfish,
blood and sometimes air or water inside the insect is forced into the thorax by the
contraction of muscles in the abdomen. This splits the exoskeleton, usually along the
middle of the back side. The crawfish repeatedly moves its tail to help shed the skin
and then crawls out. This process of shedding the exoskeleton is called molting.
Crawfish molt about 11 times in their lives, but this process stops when they reach the
adult stage.
LSU AgCenter • 4-H Youth Wetlands Program • 2015 • Upper Elementary • Crawfish 101
5. Demonstrate how to pull the balloon out. Use one hand to gently hold the exoskeleton and tug
the balloon with the other hand. Don’t rip the paper on purpose to get it out. Instead, slowly
tug on the balloon in different directions until the balloon slides out. The paper may get torn
slightly from the tugging. Just be gentle and patient, and it will happen. A crawfish has to do
the same thing with its tail’s movement helping it exit the old exoskeleton.
a. When the crawfish first crawls out of its old exoskeleton, its new exoskeleton is still
moist and flexible – like the wet paper strips when they were put on the balloon. The
crawfish gulps in air or water to expand the flexible exoskeleton before it dries and
hardens like the paper strips. The dried, stretched exoskeleton provides growing space
until the next molt.
6. Show the balloon that represents the fragile crawfish. Since the crawfish has lost its
exoskeleton, it has nothing to protect it from predators or the elements.
a. What do you think the crawfish does now? (It hides in its burrow.)
7. Allow students to reflect in their science journals about:
a. What it means to have no bones but to have an exoskeleton.
b. What happens if part of the exoskeleton rips during molting?
c. Where crawfish go after they have molted?
d. What types of threats the crawfish might be susceptible to right after molting?
8. Pass out the Crawfish 101 Quiz to individual students.
9. Collect and grade the quiz, using the Crawfish 101 Quiz KEY.
Extension Ideas:
 Wikihow: Catch live crawfish by building a crawfish trap!
www.wikihow.com/Make-a-Crawfish-Trap
 If available, show students live examples of both the red swamp crawfish and the white river
crawfish. Students can compare and contrast them. See LSU AgCenter: Crawfish Biology in
the resource section of this lesson plan for a link to a detailed comparison and contrast.
Blackline Masters:
 Crawfish Parts and Functions
 Crawfish Parts and Functions KEY
 Vocabulary
 Live Crawfish Exploration
 Crawfish Comparison Chart
 Crawfish Comparison Chart KEY
 Crawfish Quiz
 Crawfish Quiz KEY
Resources:
Blaxland, Beth. Crabs, Crayfishes and Their Relatives (2002). Macmillan: Australia
LSU AgCenter • 4-H Youth Wetlands Program • 2015 • Upper Elementary • Crawfish 101
Downing, Johnette. Why the Crawfish Lives in the Mud (2009). Pelican Publishing Co.: Gretna, La.
(Summary: When crawfish takes advantage of crab’s generosity, his trickery costs him his
friendship.)
Education.com Balloon Molting Lesson (adapted).
www.education.com/science-fair/article/break1
Foss Web: Crawfish Resources
http://lhsfoss.org/fossweb/teachers/materials/plantanimal/crayfish.html
Grimm, Phyllis W. Crayfish (2001). Learner Publication Co.: Minneapolis: Minn.
Kalman, Bobbie. The Life Cycle of a Crayfish (2007). Crabtree Publishing Co.: New York, N.Y.
Louisiana Public Broadcasting: Crawfish Observation
www.lpb.org/education/classroom/itv/crawfish/crawfish1.pdf
Louisiana Seafood News: Crawfish Picture for Media Use
www.louisianaseafoodnews.com/2013/03/11/lenten-season-creates-opportunities-forfishermen/crawfish/
LSU Agricultural Center: Crawfish Biology
http://text.lsuagcenter.com/NR/rdonlyres/86E9F5D0-6D8A-436B-BF838D7C21258C1D/41301/chapter2.pdf
Microsoft Office Clip Art: Clip Art Images
http://office.microsoft.com/en-us/images/?CTT=97
So Cool Science: Insects Shedding Exoskeleton and Papier-mache Balloon Experiment
www.youtube.com/watch?v=fUsEV0OOq6M
Virginia Cooperative Extension: The Control of Burrowing Crayfish in Ponds
http://pubs.ext.vt.edu/420/420-253/420-253.html
LSU AgCenter • 4-H Youth Wetlands Program • 2015 • Upper Elementary • Crawfish 101
Name ______________________________________________ Date _____
Crawfish 101
student activity sheet
Vocabulary
Swimmerettes
Cheliped/pincer
Abdomen
Walking legs
Compound eye
Short and long
antennae
Wetlands Program
provided by LSU AgCenter
provided by LSU AgCenter
Actual function: ___________________________
Wetlands Program
Actual Function: __________________
________________________________
Actual Function: __________________
________________________________
Predicted Function: ________________
______________________________
Part Name: ______________________________
Predicted Function: ________________________
________________________________________
Predicted Function: ________________
Part Name: ______________________________
Predicted Function: ________________________
Actual Function: ____________________________
__________________________________________
Part Name: _______________________
Predicted Function: _____________
Actual Function: __________________
________________________________
Part Name: _____________________
Crawfish 101
student activity sheet
Part Name: _______________________
Predicted Function: __________________
___________________________________
Actual Function: _____________________
Part Name: _______________________
Crawfish Parts and Functions Chart
Name ___________________________________________ Date ___________________
Wetlands Program
provided by LSU AgCenter
Actual Function: Walking in different directions,
picking up food
Predicted Function: Answers may vary
Actual Function: Aids in swimming
Actual Function: Holding food in
place, burrowing
Predicted Function: Answers may vary
Part Name: Walking legs
Predicted Function: Answers may vary
Actual Function: Sensory organs for feeling, tasting
Predicted Function: Answers may vary
Part Name: Long and short antannae
Part Name: Chelipeds/pincers
Actual Function: Seeing in all different
directions in color
Predicted Function: Answers may vary
Part Name: Compound eye
Crawfish 101
student activity sheet KEY
Part Name: Swimmerettes
Actual Function: Moving backward quickly,
swimming
Predicted Function: Answers may vary
Part Name: Abdomen
Crawfish Parts and Functions Chart
Name ___________________________________________ Date ___________________
Crawfish 101
Name ____________________________________ Date_______
student activity sheet
Live Crawfish Exploration
Anatomy Identification
1. Inspect live crawfish to find each part from the chart.
2. Complete the following information.
Body Part
Compound Eyes
Walking legs
Pincers/chelipeds
Abdomen
Swimmerettes
Antennae
Measure and Observe
Number Counted
Length (in centimeters):
Mass (in grams):
Color(s)
Smell(s)
Sound(s)
Behavior
1. A stimulus is something you do that excites an organism or part,
so you can note a reaction or function.
What do you think the crawfish will do if you reach
for it? Do not do it yet. Predict.
Reach for the crawfish, but do not touch it.
What did it do?
2. Focus on these specific stimuli. Write the results in the response column.
Note: Be gentle with the crawfish. Do not pull or poke roughly. You may want to pick up the crawfish, as
instructed, to perform this part of the exploration.
Body Part
Walking legs
Abdomen
Swimmerettes
Antennae
Stimulus
Light touch
Light touch
Light touch
Light touch
Response
3. Observe the tail fin. Does it bend? If it does, that means it is jointed. What part of your body is jointed?
Explain how that one of your body parts is similar to the tail fin of the crawfish. How is it different?
4. Place the crawfish on the table. What did it do? Observe how it moves and what body parts are used to
accomplish different tasks.
Wetlands Program
provided by LSU AgCenter
Name ____________________________________ Date_______
Crawfish 101
Live Crawfish Exploration
(continued)
Functions
Pick up your crawfish and gently rub the exoskeleton of the crawfish. Make sure not to rub near the
pincers. What does it feel like? Why does it feel like
that?
Gently squeeze the cephalothorax and then
squeeze gently nearer to its tail? Do those places
feel the same or different? Explain. What do you
think is the function of the cephalothorax?
Try the different methods of feeding the crawfish
that are shown to the right.
Crawfish Feeding Methods
What does the crawfish do when you try to feed it?
•
•
•
When it is eating the meat, what do you observe? Be
specific.
Place the crawfish in the water and put meat in
the water next to it.
Place a piece of meat on one of its free pincers.
Dip meat on a toothpick into the water and
place it near the crawfish’s mouth so the water
runs into its mouth.
Place the crawfish back in the clear
container of water. Observe it. What
did it do? What parts were used?
Wetlands Program
Join another pair of students. Put your
crawfish facing their crawfish on the
table. What do they do?
provided by LSU AgCenter
Name ____________________________________ Date_______
Crawfish 101
student activity sheet
Crawfish Comparison Chart
Directions: After observing the crawfish in class today, compare and contrast the crawfish with other animals found in
Louisiana. Write one similarity and one difference for each. Do not mention color in what you write. Instead, use parts of the
anatomy and the functions of each. You may use jots. One example has been completed for you.
Similarity: Both have claws to help capture food
Similarity: __________________________________
Difference: Body shape is wider for crab
Difference: _________________________________
Similarity: _________________________________
Similarity: ________________________________
Difference: _______________________________
Difference: _______________________________
Similarity: _______________________________
Similarity: ________________________________
Difference: _______________________________
Difference: _______________________________
Wetlands Program
provided by LSU AgCenter
Crawfish 101
Name ____________________________________ Date_______
student activity sheet-KEY
Crawfish Comparison Chart
Directions: After observing the crawfish in class today, compare and contrast the crawfish with other animals found in
Louisiana. Write one similarity and one difference for each. Do not mention color in what you write. Instead, use parts of the
anatomy and the functions of each. You may use jots. One example has been completed for you. (Possible answers given.
Students’ answers may vary.)
Similarity: Both have claws to help capture food
Similarity: Both have legs for walking
Difference: Body shape is wider for crab
Difference: Does not have claws
Similarity: Both have a tail
Similarity: Both invertebrates
Difference: can fly
Difference: Lives only in the water
Similarity: Grabs its food
Similarity: Has more than two walking legs
Difference: Has feathers; can fly
Difference: Creates a web
Wetlands Program
provided by LSU AgCenter
Crawfish 101
Name ____________________________________ Date_______
student activity sheet
Crawfish 101: Quiz
Directions: Read the following selection carefully.
If the water dries out of a nearby ditch, a crawfish will dig a hole called a burrow in the mud next to the ditch. It builds a mud
tower that looks like a smokestack on top of its burrow. The burrow goes down into the ground like an ant tunnel. The crawfish
then lives inside the moist, cool burrow under the tower until it rains. When it rains heavily, the tower will wash away, but the
crawfish is safe deep inside the burrow. The crawfish stays in its home until the storm has ended.
Directions: Read each statement and determine if it is true or false. Refer to the selection
above for eviden to support your answer. (2 points each)
1.
2.
3.
4.
Crawfish build their own homes. ___________________
Crawfish live near water. ________________________
Crawfish enjoy hot, dry weather. ___________________
Crawfish build their homes and towers from grass and leaves. ____________________
Directions: Use the selection above to answer the following short answer questions.
5.
What do you think the crawfish will do after a heavy rain ends? Explain by providing evidence from
the selection to support your answer. (2 points)
6.
Which parts of the crawfish’s outer anatomy will be used to build the burrow? Choose two parts of
the anatomy and explain how each will be used to help build the burrow. (4 points)
7.
What does molting mean for an arthropod? Explain how the crawfish will use its burrow during the
molting process. (2 points)
Directions: Fill in the blanks. (1 point each blank)
Crawfish are decapods, meaning they have how many legs? __________
Crawfish are _______________________ along with shrimp, crabs and lobsters.
In Louisiana, there are at least two other terms for crawfish. Those are: _______________________________
Crawfish are omnivores. This means they eat both __________________and ______________________.
The hard outer shell of the crawfish is called the ____________________________________.
Wetlands Program
provided by LSU AgCenter
Crawfish 101
Name ____________________________________ Date_______
student activity sheet-KEY
Crawfish 101: Quiz
Directions: Read the following selection carefully.
If the water dries out of a nearby ditch, a crawfish will dig a hole called a burrow in the mud next to the ditch. It builds a mud
tower that looks like a smokestack on top of its burrow. The burrow goes down into the ground like an ant tunnel. The crawfish
then lives inside the moist, cool burrow under the tower until it rains. When it rains heavily, the tower will wash away, but the
crawfish is safe deep inside the burrow. The crawfish stays in its home until the storm has ended.
Directions: Read each statement and determine if it is true or false. Refer to the selection
above for eviden to support your answer. (2 points each)
1.
2.
3.
4.
Crawfish build their own homes. True
Crawfish live near water. True
Crawfish enjoy hot, dry weather. False
Crawfish build their homes and towers from grass and leaves. False
Directions: Use the selection above to answer the following short answer questions.
5.
What do you think the crawfish will do after a heavy rain ends? Explain by providing evidence from
the selection to support your answer. (2 points) Rebuild the tower because it washed away.
6.
Which parts of the crawfish’s outer anatomy will be used to build the burrow? Choose two parts of
the anatomy and explain how each will be used to help build the burrow. (4 points)
(Some possible answers include, although answers may vary:
Claws – grabbing and placing mud, burrowing into the ground and moving mud to the side;
Legs – walking in and out of the burrow;
Eyes – to see what crawfish is doing; and
Tail – for pushing mud out of the way)
7.
What does molting mean for an arthropod? Explain how the crawfish will use its burrow during the
molting process. (2 points)
Molting occurs when an invertebrate has outgrown its exoskeleton. It eventually will shed the exoskeleton
during the molting process. After a crawfish sheds its exoskeleton, it will stay inside its burrow for protection, since it lost the protection of its exoskeleton.
Directions: Fill in the blanks. (1 point each blank)
Crawfish are decapods, meaning they have how many legs? 10
Crawfish are crustaceans – along with shrimp, crabs and lobsters.
In Louisiana, there are at least two other terms for crawfish. Those are: crawdad, mudbug, crayfish.
Crawfish are omnivores. This means they eat both meat and plants.
The hard outer shell of the crawfish is called the exoskeleton.
Wetlands Program
provided by LSU AgCenter