cool factact - coral reefmanta rays have flat, wing-like fins on each side of their body. they use...

Activity #5

Manta Mysteries

Cool WCool WorordsdsCartilageTough and flexible skeletal tissue

ZooplanktonTiny animals that drift in the water

Cephalic finsThe pair of fins on either side of a manta ray’s head

Acoustic tagA small device that sends out sound waves

Acoustic receiverA device that gathers sound wave data

Cool FCool Factact

Manta rays were named for their wide,flat bodies. Manta means “blanket” inSpanish.

Immersion Presents Secrets of the Gulf1

© Kaile Tsapis

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Immersion Presents Secrets of the Gulf

Manta rays are large, graceful animals that live in warm ocean waters. Like sharks, they haveno bones. Their skeleton is made of a tough, flexible tissue called cartilage (KAR tuh lihj)—the samematerial that’s in the tip of your nose. Manta rays have flat, wing-like fins on each side of their body.They use these fins to fly through the water.

Adult manta rays can be more than 20 ft (6 m) across. Although mantas are very large, their foodis very small. Mantas eat zooplankton (ZOH plank tun), which are tiny animals that drift in thewater. As a manta swims, it uses the specialized cephalic (seh FA lihk) fins on either side of itshead to help direct food and water into its mouth.

Researchers at the Flower Garden Banks have been interested in manta rays for a long time. Theyknow basic things such as how mantas look and what mantas eat. But they have many unansweredquestions. Do any mantas live at the Flower Garden Banks year-round? How far do mantas travelin their lifetime? How many mantas live in the world’s oceans?

To answer these questions, researchers need to be able to identify individual manta rays. Mantaslook similar from above. But every manta has a one-of-a-kind spot pattern on its belly. For severalyears, divers at the Flower Garden Banks have been photographing manta rays from below. All ofthe photographs go into a catalog. The catalog currently includes more than 25 different mantas.

Photographs help researchers identify manta rays. But some researchers want to do more thanjust identify the mantas. Dr. Rachel Graham and Dan Castellanos want to know how and why mantasmove from place to place. They started a research project in 2006 to investigate the movementpatterns of mantas at the Flower Garden Banks.

Graham and Castellanos went on three research cruises tothe Flower Garden Banks between February and October2006. They looked for mantas during each cruise.Castellanos used a long pole and a plastic dart to insert anacoustic (uh KOO stihk) tag into six of the mantas that they found. An acoustic tag is a small device that sends outsound waves. Each tag sends out a distinct pattern ofsound waves.

Dan Castellanos prepares to tag a manta ray.© FGBNMS/Hickerson

3Graham and Castellanos also set up three acoustic receivers. An acoustic receiver gatherssound wave data. When a tagged manta swims close to an acoustic receiver, the receiverrecords the identity of the manta, the date, the time, and other data. The three acousticreceivers are at the East Flower Garden Bank, the West Flower Garden Bank, and StetsonBank. Graham and Castellanos hope to set up more receivers in the future.

This research is still new. But there are already someimportant findings. A manta ray that was tagged at theEast Bank was found to have visited the West Bank,which is 12 mi (19 km) away. This shows that the twobanks are connected by more than just water. Livingthings that travel between the two banks might travel toother areas, too. Following mantas could help scientistslearn more about connections between the FlowerGarden Banks and the rest of the Gulf.

During the Secrets of the Gulf expedition, Graham andCastellanos gathered new data on the movements ofthe tagged mantas. They also looked for more mantas

to tag. They hope that their research continues to unlock some of the unsolved mysteries ofmanta rays.

Now that you know the basics of

manta ray research at the Flower

Garden Banks, follow the steps on

the next page to try your hand at

identifying mantas!

Immersion Presents Secrets of the Gulf .

A tagged manta ray swims near the acousticreceiver at the East Flower Garden Bank.

© FGBNMS/Hickerson

acousticreceiver

4

Ready to Begin?

Steps

1. Six participants should tape a mantaray spot pattern to their shirt.These participants will playthe role of manta rays nearthe East Flower Garden Bank.

2. The rest of the participants shouldchoose a place to stand in the room.These participants will play the role ofscuba divers at the East Flower GardenBank. Their goal is to correctly identify asmany manta rays as possible.

3. When the leader says to begin, themanta rays should begin to walk around theroom. They can walk in a straight line, spin incircles, or stand still. They should flap theirarms back and forth in a wing-like motion asthey walk.

4. The scuba divers can also walk around theroom, but they must not touch the mantas.

Each scuba diver should use the MantaRay Photo Catalog to identify asmany of the manta rays as possible.

5. After a few minutes, the leader will telleveryone to stop. At this point, the scubadivers should make a final list of the mantas that they identified.

6. The leader will then reveal the correctidentities of the mantas that were in the

game. Scuba divers should keep track ofthe number of mantas that they identified correctly.

7. Play the game at least twice before discussing the results.

Immersion Presents Secrets of the Gulf

Activity

In this activity, you will play a game to practice identifying manta rays.

Materials

Manta Ray Photo Catalog

manta ray spot patterns

masking tape

notebook

pencil

5Immersion Presents Secrets of the Gulf .

Taking It Further Activity:

Add Acoustic Receivers

Play the game again, but this time use two separate play-ing areas to represent the East Flower Garden Bank andthe West Flower Garden Bank. The manta rays can gobetween the banks, but the scuba divers must stay at asingle bank. One participant at each bank should playthe role of an acoustic receiver. The acoustic receivershould have a notebook and a pencil. Whenever a mantaray arrives at or departs from a bank, it must check in with the acoustic receiver. The acousticreceiver must record the name of the manta and the time of its arrival or departure. The scubadivers should also try to record what time it is when they identify a manta ray. After playing oneor two rounds of the game in this way, discuss how it is different from the original version of thegame. What new information is gathered in this version? What information about the move-ments of the manta rays is still unknown?

Think About It

Rachel Graham and Dan Castellanos hope to add moreacoustic receivers to other banks as well as to oil and gas

platforms. How will having more receivers help the researchersimprove their data? How else could the researchers improve their

data?

6Immersion Presents Secrets of the Gulf

Manta 1 Manta 2

Manta 3 Manta 4

Manta 5 Manta 6

Manta 7 Manta 8

Manta Ray Photo Catalog

© FGBNMS/Hickerson

© FGBNMS/Hickerson

© Joyce and Frank Burek

© FGBNMS/Schmahl

© FGBNMS/Hickerson

© TPWD

© Gary Merritt

© Joyce and Frank Burek

Immersion Presents Secrets of the Gulf .

Activity #5

Manta Mysteries

SummarSummaryy

In this activity, participants play a game tosimulate the identification of manta rays inthe field.

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Difficulty: Easy to Medium

Suggested Group Size: 12 to 25

Time: 45 minutes

GoalsParticipants will:

A. learn how photographs help researchers identify manta rays

B. describe how acoustic tagging is being used to investigate manta ray movement patterns at the Flower Garden Banks

C. play a game to simulate the identification of manta rays in the field

MaterialsFor each “scuba diver” participant:

• Manta Ray Photo Catalog• notebook• pencil

For each “manta ray” participant:• manta ray spot pattern• masking tape

For the leader:• Manta Ray Spot Patterns 1–8• scissors• 8 pieces of cardstock, 8.5-in. x 11-in.• glue stick• Manta Ray Spot Patterns Answer Key

For the Taking It Further Activity:• 2 chairs• clock or stopwatches

Cool Words

CartilageTough and flexible skeletal tissue

ZooplanktonTiny animals that drift in the water

Cephalic finsThe pair of fins on either side of a manta ray’shead

Acoustic tagA small device that sends out sound waves

Acoustic receiverA device that gathers sound wave data

Leader Notes


Think About It

Rachel Graham and Dan Castellanos hopeto add more acoustic receivers to otherbanks as well as to oil and gas platforms.How will having more receivers help theresearchers improve their data? How elsecould the researchers improve their data?Having more acoustic receivers will helpGraham and Castellanos keep track of themantas at more locations over a greaterarea. However, they will still be unable to follow the mantas at all times, as the mantas cannot be tracked when they arenot close to a receiver. (Graham andCastellanos intended to test the range of thereceivers at the Flower Garden Banks in2006, but they were unable to do so due tostrong currents and lack of time. They knowthat the typical range of similar receiversunder similar conditions in Belize is about1,650 ft (500 m) in all directions.)

In order to get a more comprehensive lookat the movement patterns of mantas in theFlower Garden Banks area, Graham andCastellanos could tag more mantas. Theycould also use another kind of tagging system, such as satellite tags. One type ofsatellite tag records temperature, depth,and light level data over a certain period oftime. After data collection is complete, thetag releases from the manta and floats tothe surface to transmit the data. A satelliteorbiting Earth receives the data and sendsthem to researchers via e-mail. Theresearchers can use the data to estimatethe movements of the manta during thetime it was wearing the tag. Graham andCastellanos plan to tag more mantas. Theyalso might explore satellite tagging in thefuture.

Extra Background

You might want to share with participantsthat Rachel Graham and Dan Castellanos tryto minimize any pain that mantas might feelduring the tagging procedure. Mantas tendto react when they are tagged, but each onereacts differently. Some swim away quicklyas soon as they are tagged. Others start toswim away but then come right back tohang out with the scuba divers in the water.Graham and Castellanos use plastic dartswhen they tag mantas because they believethat they are less painful to the mantas thanmetal darts. The darts are only a coupleinches long and a couple centimeters wide.When Graham and Castellanos tag mantas,they approach the animals in their blindspot. This way the mantas do not see themand do not associate humans with the tagging event. In general, mantas seemmore startled or surprised than anythingelse when they are tagged.

The acoustic tags and the acoustic receiversare battery operated. The batteries in theacoustic tags are designed to last at leastthree years. When the batteries in a tag die,the tag no longer transmits sound waves.Eventually, the tag falls off the manta. Thebatteries in the acoustic receivers last about15 months. Graham and Castellanoschange the batteries in the receivers everytime they go back to the Flower GardenBanks, or at least every six months.


Set-Up

Make a copy of the Manta Ray PhotoCatalog for each participant.

Prepare the manta ray spot patterns priorto beginning the activity. First cut out eachspot pattern. Then use a glue stick to mounteach pattern on an 8.5-in. x 11-in. piece ofcardstock. The cardstock will give the patterns more stability. If possible, laminatethe cardstock and patterns to give themeven more stability. You might want to writea small note on the back of each card tohelp you remember which manta is which(use the information on the Manta Ray SpotPatterns Answer Key).

This activity is best done in a large openspace such as a gym.

Working With Groups

This activity works best in a large group of atleast 12 participants.

Activity Notes

Split the participants into two groups: mantarays and scuba divers. For the first round ofthe game, six participants should be mantarays and the rest of the participants shouldbe scuba divers. In this round, use onlyManta Ray Spot Patterns 1–6. Have each ofthe manta rays use masking tape to affixone of the manta ray spot patterns to thefront of their shirt, over their belly.

After the manta rays are ready, distribute acopy of the Manta Ray Photo Catalog toeach scuba diver. Also make sure that thescuba divers have notebooks and pencils sothat they can record their manta ray identifications.

Have the manta rays stand with their spotpatterns facing a wall while the scuba diversspread out in the room. After all of thescuba divers are in place, announce that it istime to begin and tell the manta rays to moveaway from the wall. Remind all participants towalk at all times during the game.

Depending on the size of the group, eachround of the game should last between oneand five minutes. Allow enough time so thateach scuba diver has a chance to correctlyidentify at least a few mantas. Do not allowso much time that all of the scuba divers areable to correctly identify all of the manta rays.

After the first round of the game is over,have participants switch roles. For the second round of the game:

• If you have fewer than 16 participants,have half of the participants be mantarays and have the other half be scubadivers.

• If you have 16 or more participants,have eight of the participants be mantarays and have the rest be scuba divers.

If you wish, include Manta Ray Spot Patterns7 and 8 in the second round. Note thatthese two spot patterns do not match up toany of the mantas in the Manta Ray PhotoCatalog. They represent manta rays thathave not yet been identified. Do not sharethis information with participants—let themfigure out how to deal with the mystery man-tas during the course of the game.

Also note that Manta 3 and Manta 7 fromthe Manta Ray Photo Catalog do not appearon any of the Manta Ray Spot Patternsheets. They represent mantas that wereidentified previously at the Flower GardenBanks but are not currently in the area.

4After participants have played two rounds ofthe game (or more, if desired), have themdiscuss the experience as a group. If youchose to include Manta Ray Spot Patterns 7and 8, discuss with participants how theyhandled seeing mantas that were not includedin the Manta Ray Photo Catalog. Some participants might have tried to force a fitbetween the mystery mantas and the mantas in the catalog. Others might havedecided to not identify those mantas. Stillothers might have tried to sketch the spotpatterns of the mantas in order to establishthem as new identifications.

Optional: Have participants do the activityagain, but this time do not allow the scubadivers to carry the Manta Ray Photo Catalogwith them. Instead, have them carry onlytheir notebooks and pencils. Have themsketch the spot patterns of any mantas thatthey see. Then, after the game is over, havethem try to match up their sketches to themantas in the photo catalog. Have them discuss whether it was easier or harder toidentify the mantas this way. In reality, scubadivers do not usually bring a photo cataloginto the water with them. Instead, theysketch or photograph the mantas that theysee. Only later do they compare the imagesto the mantas in a photo catalog.

Taking It Further Activity

If possible, set up two playing areas at least30 ft (9 m) apart. Have one participant ineach area play the role of an acoustic receiver.Each acoustic receiver should sit in a chairwith a notebook and a pencil. If there is novisible clock in the playing area, supply eachacoustic receiver with a clock or stopwatch.

Remind the manta rays that in this versionof the game, they must check in with theacoustic receiver whenever they arrive at ordepart from a bank. Either allow the mantarays to decide on their own how often tomove between the banks, or assign themmovement patterns (e.g., two mantas stay atthe East Bank; two mantas stay at the WestBank; and two mantas travel between thebanks). After playing one or two rounds ofthe game in this way, ask participants to sharehow this version differs from the originalversion of the game. Participants shouldexplain that this version includes informationabout time. Knowing how long a manta waswithin range of an acoustic receiver is potentially more useful than knowing onlythat the manta was identified as being in thearea. Even in this version of the game, someinformation about the movements of themantas is still unknown. For example, nodata exist for the time periods when themantas are between the banks.

Discussion Questions

How are photographs helpful toresearchers in identifying manta rays? (Thebelly of every manta ray has a unique spotpattern. Divers take photographs of thesespot patterns. The photographs are then putinto a catalog that researchers can use toidentify manta rays in the field.)

What is one of the goals of the mantaray research project that Rachel Grahamand Dan Castellanos began in 2006? (Oneof the goals of the manta ray research project is to learn more about the movement patterns of manta rays at theFlower Garden Banks.)


What are some advantages of usingacoustic tags to track manta rays? Whatare some disadvantages? (One advantageis that acoustic receivers can gather dataabout manta rays even when no people arepresent in the water. Also, the manta raysdo not have to be in a particular position—such as belly-down—for the acousticreceivers to identify them. Finally, theacoustic receivers can track the movementsof the mantas over time. A disadvantage isthat the acoustic receivers cannot track allmanta rays—they can track only manta raysthat carry acoustic tags. Also, there are alimited number of acoustic receivers, andeach one has a limited range; the receiverscannot track mantas in all places at alltimes.)

One of the manta rays that Grahamand Castellanos tagged at the East FlowerGarden Bank was later found to have visitedthe West Flower Garden Bank. Why is thisan important finding? (This is an importantfinding because it shows that the East Bankand West Bank are connected. Scientistsknow that the banks are connected bywater, but they did not have any prior evidence of a single large fish visiting bothbanks. If one manta was observed to do this,maybe other mantas and even other typesof marine life also move between the banks.It is possible that manta rays seen at theFlower Garden Banks travel to other banks,too. They might also travel to oil and gasplatforms. Researchers are very interestedin learning more about how different areasof the Gulf are connected to one another.Understanding these connections can helpscientists better manage and conserve theresources of the entire Gulf region.)

As a scuba diver, what was the easiestpart of this game? What was the hardestpart? (Answers will vary. Participants mightsay that the easiest part was identifying amanta ray when its belly was facing them.They might say that the hardest part was fig-uring out what to do when they saw a mantathat was not present in the Manta RayPhoto Catalog.)

Additional Information

Books

Sharks and Rays of the World, by DougPerrine.

Sharks, Skates, and Rays of the Gulf ofMexico: A Field Guide, by Glenn R. Parsons.

Videos

Manta Ray Videos (online), produced byManta Pacific Research Foundation.

Web Sites

Flower Garden Banks National MarineSanctuary Web site

Immersion Presents Web site

The Manta Network’s Indo-Pacific MantaMigration Study Web page

Manta Pacific Research Foundation’s KonaRay Manta ID Catalog Web site

ReefQuest Centre for Shark Research’sManta Ray (Manta birostris) FAQ Web page

Note: Links to all Web resources can be foundat www.immersionpresents.org/gulf/links.html.


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Manta Ray Spot Patterns Answer Key

= Manta 1

Manta Ray Spot Pattern 1

= Manta 4


= Manta 6


= not inManta RayPhotoCatalog


= Manta 2


= Manta 5


= Manta 8



= not inManta RayPhotoCatalog

cool factact - coral reefmanta rays have flat, wing-like fins on each side of their body. they use...

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