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SADDLE UP WITH SEAHORSES!
MASTER TEACHER Helen Mebane
GRADES 5 - 8
OVERVIEW
Students will be introduced to a unique fish found in our marine
habitat called seahorses. Seahorses belong to the species Hippocampus
which comes from a Greek word meaning “bent horse.” Students will view
a video showing their interesting external body parts, eating habits,
reproduction, and how they live in their habitat. The students will also
label a drawing of both the male and female seahorse and an Australian Sea
Dragon Phycodurus eques.
ETV SERIES
Wonders Under the Sea-#409 Family of Fishes: The
Seahorses
LEARNING OBJECTIVES
Students will be able to:
* list the seahorses’ unique characteristics (head, snout,
eyes, body, fins, male’s brood pouch)
* identify the function of seahorses’ dorsal and pectoral fins
* discuss how seahorses reproduce
* identify seahorses’ marine habitat and their food sources
* color and label a drawing of a male and female seahorse and an
Australian Sea Dragon
MATERIALS
(per student)
Activity Sheet with 20 questions pertaining to the video
Handout with drawings of a male and a female seahorse and an
Australian Sea Dragon
Map colors
VOCABULARY
seahorse: a unique fish with a head which resembles a
tiny horse.
armor plating: scales that have fused together.
dorsal fin: the transparent fin located on the fish’s back.
pectoral fins: two fins located on either side of the
head behind the eyes.
caudal fin: the tail fin of the fish.
brood pouch: an incubation pocket where the young
seahorses develop.
abdomen: the portion of the animal containing the
intestines.
bony fish: fish with endoskeletons which is made of bones
such as seahorses, red drum, and trout.
prehensile tail: the unique tail that the seahorse uses
to holds on to sea grass or coral.
crustaceans: invertebrate such as brine shrimp and crabs.
invertebrates: animals without backbones.
marine habitat: saltwater environment such as Gulf of
Mexico or oceans.
gestation period: the time in which the male seahorse
carries the young in his brood pouch
PRE-VIEWING ACTIVITIES
Ask the students if they have ever seen a live seahorse.
Say, “Today we are going to watch a video about seahorses and learn about
their unique body features and functions. You will also be given an opportunity
to view a live pipefish (cousin to the seahorses) which was caught at Port
Aransas using a push net. With the help of your parents, you may build
your own push net to catch your own marine animals.”
FOCUS FOR VIEWING
Say, “As part of our study of bony fish, we will view the
external part of a seahorse and learn their functions.” To give the
students a specific responsibility while viewing say, “Listen to the video to
learn the different characteristics of the male and the female seahorse and the
make up of their armor plating.” Find some interesting facts about these
seahorses such as the differences in sex and armor plating.” Teacher
then passes out the activity sheet. As we view the video, students will be
answering the questions from the activity sheet at the end of the lesson.
Students are to record their answers as the tape is viewed.
VIEWING ACTIVITIES
Begin where Karen James introduces Tom Schmid from the
Texas State Aquarium. Karen says, “But first lets join Tom Schmid and a
group of aquarium sea campers out on the deck to learn more about seahorses.”
Pause the tape after you hear “armor plating”. This is the
answer given to first child’s question of “Do seashores have
scales?” Have students look at the activity sheet, review the first
question on the handout. (They have scales, but their scales have been modified
into armor plating. They are fused together to form real hard, armor
plating around their body. Its head looks similar to a horse’s
head.)
Resume the tape. Pause the tape after you
hear, “dorsal and pectoral fins.” This is the answer given to second
child’s question of, “Do seahorses have fins?” On the activity
sheet, review the second question on the handout. (They do have fins.
They are located so the seahorse can see upright. Since the seahorse swims
a little differently...they still use dorsal and pectoral fins).
Resume the tape. Pause the tape after you
hear, “… the male gives birth to babies.” This is the answer given
to third child’s question of “Which seahorse has the babies?”
On the activity sheet, review the third question on the handout.
(Normally, the female lays the eggs. But female seahorses then give the
eggs to the male. The male fertilizes the eggs in his brood pouch where
they stay until they are born. The brood pouch is located on his abdomen.
So female gives the eggs to the male which gives birth to young.)
Resume the tape. Pause the tape after you
hear, “…pectoral fin on the sides of head.” This is the answer given
to fourth child’s question of, “How do seahorses swim?” On the
activity sheet, review the fourth question on the handout. (Most fish use
caudal fin to propel them through the water. But since seahorses are
vertical to the water column their dorsal fin propels them through the water.
The pectoral fins, which are on the side of the head, help them navigate through
the water.)
Resume the tape. Pause the tape after you
hear, “saltwater or grassland environment.” This is the answer given
to fifth child’s question of, “Where do seahorses live?” On
the activity sheet, review the fifth question on the handout. (You can
find seahorses in the saltwater oceans all over the world. Seahorses live
in a marine environment and different species live in grass flats, shore areas,
and maybe even around Corpus Christi Bay and Port Aransas. They live
anywhere there is saltwater and a grassland environment.)
Resume the tape. Pause the tape after you
hear, “bony fish.” This is the answer given to Karen’s question by
Sally Hoke, guest speaker of Texas State Aquarium. Karen asks, “Are
seahorses unusual fish?” On the activity sheet, review the sixth
question on the handout. All of the rest of the questions will be asked by
Karen and Sally will answer them. (Seahorses are classified as bony fish
just like red drum, snapper, or trout. Seahorses have an unique
appearance. They look like a pez dispenser. Their head is at a 90
degree angle to the rest of their bodies, giving it a vertical appearance. The
red drum’s head is connected to the backbone in a continuous line.)
Resume the tape. Pause the tape after you
hear, “…higher up on evolutionary scale.” Next question asked is, “Are
seahorses prehistoric?” On the activity sheet, review the seventh
question on the handout. (Although, scientists classify seahorses up
higher on the evolutionary scale; they are not prehistoric.)
Resume the tape. Pause the tape after you
hear, “…have binocular vision.” Next question asked is, “What
about the seahorses’ eyes?” On the activity sheet, review the eighth
question on the handout. (Each eye can move independent of each other.
They can see in two different directions at once. They can focus forward
like we do...they have binocular vision.)
Resume the tape. Pause the tape after you
hear, “…hang on to sea grasses or coral.” Next question asked is,
“How do seahorses use their tails?” On the activity sheet, review the
ninth question on the handout. (Seahorses use their prehensile tail just like a
monkey does. They hang on to sea grasses or coral where they wait
for food to come along.)
Resume the tape. Pause the tape after you
hear, “…two days to swim a mile.” Next question asked is, “With
their tiny fin, how fast do seahorses swim?” On the activity sheet,
review the tenth question on the handout. (Seahorses do have the ability
to move. Their fins on either side of their head behind the eyes are
called the pectoral fins. They also have a transparent, fluttering fin
called a dorsal fin which helps the seahorse move through the water. On
the dorsal fin, there are rays which move independent of each other which create
a wave affect.)
Resume the tape. Pause the tape after you
hear, “…tube-like snout.” The next question asked is, “How do
seahorses catch their food if they move so slowly?” On the activity
sheet, review the eleventh question on the handout. (Seahorses
us their tail to hang on to something, they camouflage their bodies to match
with the environment, they wait for food to come to them, and they use their
tube-like snout to catch food.)
Resume the tape. Pause the tape after you
hear, “…live food.” Next question asked is, “What do seahorses
eat?” On the activity sheet, review the twelfth question on the handout.
(Seahorses eat small crustaceans, small fish, and other live food. They
are very picky eaters.)
Resume the tape. Pause the tape after you
hear, “…male seahorse bear them.” The next question asked is, “How
do the seahorses reproduce?” On the activity sheet, review the thirteenth
question on the handout. (The female produces the eggs. She deposits the eggs
into the male brood pouch and the male then fertilizes them. The seahorses
then swim in a intertwining pattern down the volume of the water. She
swims away after she is done. That’s all she sees of her young.)
Resume the tape. Pause the tape after you
hear, “…seahorses get oxygen from pouch.” Next question asked is,
“How are the eggs nourished?” On the activity sheet, review the
fourteenth question on the handout. (The eggs have a yolk sac which nourishes
them. The male seahorse has many more blood vessels in the pouch than the rest
of the seahorses’ body which provides oxygen to the young.)
Resume the tape. Pause the tape after you
hear, “…eight to ten days”. The next question asked is, “How long
do the young seahorses stay in the pouch?” On the activity sheet, review
the fifteenth question on the handout. (It takes eight to ten days for
eggs to develop. The male then bends back and forces the young out the
opening on the brood pouch. They may have from a few hundred to a few
dozen young. Survival is very low because they are prime food for other
fish.)
Fast forward the tape through Natalie Jenkins “The
Octopus Garden” segment.
Resume the tape after you hear, “We are back now
with our guest speaker Sally Hoke to learn more facts about seahorses.” Pause
the tape after you hear, “…between 30 to 50 different species.” The
next question asked is, “How many species of seahorses are there?” On the
activity sheet, review the sixteenth question on the handout. (There are
between 30 to 50 different species. Many problems arise with the color
variation in the same species. Scientists have difficulty telling if there is
one species of seahorses or two totally different species. There are new
species of seahorses still being discovered today.)
Resume the tape. Pause the tape after you
hear, “…number of rays on dorsal fin.” Next question asked is,
“How do you tell the differences in seahorses...is it just by color or other
adaptations?” On the activity sheet, review the seventeenth question on
the handout. (Differences in seahorses species can be determined by the
number of rays on their dorsal fin. Local marine biologists use this
technique to identify Lion seahorses which are common to our area.
Sometimes, you can tell by looking at the seahorse. Leafy Sea dragon are
found in Australia. They live in water temperatures of 50 degrees.
It is too warm for them to live here in the Gulf of Mexico. They get their
name from Chinese mythical dragons.)
Resume the tape. Pause the tape after you
hear, “slurp up their food.” The next question asked is, “How does
the Leafy Sea dragon eat their food?” On activity sheet, review the eighteenth
question on the handout. (They slurp up their food especially brine
shrimp.)
Resume the tape. Pause the tape after you
hear, “eight weeks.” Next question asked is, “How long does it take
a young Leafy Sea dragon to develop?” On the activity sheet, review the
nineteenth question on the handout. (Their gestation period is eight
weeks.)
Fast forward throughthe segment on “Pipefish.”
Resume the tape. Pause the tape after you
hear, “think before you buy seahorses at a gift shop.” The next
question asked is, “Is there anything else Sally, you wish to remind our
audience?” On the activity sheet, review the twentieth question on the
handout. (These seahorses were once live animals. Sally encourages the audience
not purchase seahorses. If people don’t buy them, there would not be a
market for them. Keep general conservation rules. Don’t pollute!)
Stop and eject the tape.
POST-VIEWING ACTIVITIES
Explain, “Now that you have a better understanding how unique
seahorses are, lets color and label this handout on male and female
seahorses.” Give each student a handout and a handful of map colors.
Also see if you and your partner can figure out this problem. If it takes
five minutes for a seahorse to travel the length of a bathtub, how many days
would it take the seahorse to travel one mile? (Hint: A bathtub is 4.5 feet in
length. You take 5 min. divided by 4.5 feet multiply by 5,280 feet divide
by 60 minutes divide by 24 hours= 4 days)
ACTION PLAN
Students could either take a field trip to the Texas State
Aquarium or write Sally Hoke, Marine Biologist from the Texas State Aquarium to
invite her to the classroom. Ask her questions: Do seahorses see in color?
How long do seahorses feed per day? Is it true that during the mating of
the seahorses, they spiral down the water column until all the eggs are
deposited into the male seahorse? Do seahorses make any sounds? Do male
seahorses ever have any birth complications? What are some uses for the seahorse
according to Chinese medicine? What is the life span of seahorses?
Students could write letters to the government expressing
their concerns of the possible destruction of seahorse population (decreasing
50% in the last five years) due to use of traditional Chinese medicine, aquarium
trade, tourist curios, and destroying of coral reef, sea grass habitat.
Have students visit the following web sites that have more
information on seahorses:
http://www.oit.itd.umich.edu/projects/adw
http://www.pbs.org.wgbh/nova/seahorse/
http://www.pbs.org.wgbh/nova/seahorse/basics.html
http://www.pbs.org.wgbh/nova/seahorse/roundup.html
http://www.sesahorse.mcgill.ca/faq.htm
#FAQ
EXTENSIONS
Science
For more information on seahorses, students may visit the
website of Texas State Aquarium: http://www.txstateaq.com SeaWorld:
http://www.seaworld.org/ask_shamu/seahorse.html
or National Aquarium in Baltimore: http://www.aqua.org./education/teachers/
Make a push lesson net. See intructions at the end of
the lesson.
Math
Research information from websites given, students could
determine the smallest to largest seahorse ever found and draw them to scale
using metric ruler and place outside classroom for student body to observe.
Art
Create a 3-D of a seahorse by first making a transparency of the
seahorses from their handout. Then place the transparency on an overhead
projector and make the seahorse as large as they wish. Students could use
any materials they wish to make giant seahorses.
Language Arts
Research information from the websites given, or read books
listed below. Student would choose and draw a seahorse of their choice,
record its scientific name, its characteristics (size, shape, and color) and
write a 1/2 page report about their seahorse. Each student would then help
to construct a marine environment outside hallways and then hang their seahorse
from the ceiling.
Read any of these books:
Garrick-Maidonent, Neil. Seahorses: Conservation and Care, August,
1997
Clark, Nikia, Sandcastle Seahorses, January, 1988
Vincent, A. C. J. The International Trade in Seahorses 1996.
TRAFFIC International. Cambridge, U.K.
Vincent, Amanda. The Improbable Seahorse, National
Geogrpahic Magazine. October, 1994.
Social Studies
Students could draw a large world map by using a
transparency. Then by researching, they would find the geographic
distribution of common seahorses. Students would place a one inch size
seahorse by the areas they are commonly found.
Activity Sheet
Directions: Answer these questions to the best of your
ability!
1. Do seahorses have scales?
2. Do seahorses have fins?
3. Which seahorse has the babies?
4. How do seahorses swim?
5. Where do seahorses live?
6. Are seahorses unusual fish?
7. Are seahorses prehistoric?
8. What about the seahorses’ eyes?
9. How do seahorses use their tails?
10. With their tiny fins, how fast do seahorses swim?
11. How do seahorses catch their food if they move so slowly?
12. What do seahorses eat?
13. How do seahorses reproduce?
14. How are the eggs nourished?
15. How long do the young seahorses stay in the pouch?
16. How many species of seahorses are there?
17. How do you tell the differences in seahorses...is it by
color or by other adaptations?
18. How do Leafy Sea dragons eat their food?
19. How long does it take young Leafy Sea dragon to develop?
20. Is there anything else Sally, you wish to remind our
audience?
Instructions: How to make a push net
You need to purchase
one 2x2 six foot piece of lumber
one 1x4 eight foot piece of lumber
one brass door handle
two 1 1/2 inch wood screws
one 3 inch carriage bolt
two 3 1/2 inch carriage bolt
five wahsers
one PVC T-connection 2 inches in diameter
50 inches length by 4 feet wide of 1/4 inch netting
one roll of nylon string from a hardware store
eighteen large staples
four horseshoe nails
Steps:
1. Using a circular saw, cut the 1x4 in half. Drill one
hole one inch on each end of these two boards. (Four holes total)
2. Place the door handle in the center of the 2x2 and attached
the door handle by using the wood screws.
3. Attach the 2x2 to the 1x4 using 3 inch bolt. Place a washer
between the 2x2 and the 1x4 board.
4. Drill two holes into the PVC T-connection about one inch from
the open ends of the PVC connection.
5. Attach the PVC T-connection to the center of other 1x4 using
two 3 1/2 bolts.
6. Spread the netting between the two1x4 and attach the netting
my using a large stapler. Use nine staples along each. 1x4 board
7. Run the nylon string all along the netting and tie to the 1x4
where the holes are located.
8. Use four horseshoe nails to attach the nylon string to
reinforce the netting on the 1x4 boards.
See the illustration:
Handout - Seahorses
*Color and label: Female Seahorse (Hippocampus),
the Male Seahorse (Hippocampus), Australian Sea Dragon (Phycodurus
eques), pectoral fin, dorsal fin, brood pouch, young seahorses
For: Teacher Use for more information on
Seahorse's Aantomy
NATIONAL.AQUARIUM IN BAI.TIMORE:
Updated: April 01, 2008
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