Gulliver Field Studies in Marine Science Students have Amazing Day Shark Tagging with the University of Miami

By Frank Gissoni

On June 19th 2015, we were greeted at the Diver’s Paradise boat at Crandon Marina by Captain Eric and the University of Miami’s RJ Dunlap Marine Conservation team. Cap and the team went over some basic rules and procedures with us. Our special guest, fishing celebrity Peter Miller, host of the TV show Bass to Billfish and proud Gulliver parent arrived at the dock with a large fresh Amberjack that he caught for our trip while filming an episode the day before.  The RJ Dunlap Team briefed the students and the rest of our group. Our team included Luis Ceballos, whose daughter was in the class, and Miller Drive Registrar Miriam Vizoso.  Our tasks would include; buoy and bait deployment, measuring the animals, taking a fin clip for future DNA analysis, and tagging the animals. We were also charged with testing the reaction of the shark’s nictitating membrane (eyelid) to determine whether the animal is under any stress during the procedure!  If any shark displayed any stress during the tagging and data collection process the team released the animal immediately.  The safety of the team and of the sharks was paramount and all information the RJ team convey was intensely absorbed by the students.  Before we knew it the engines roared and we were off.

Cruising along at idle speed through the Manatee Zone just outside of the marina, our optimism was palpable.  After all, we all had reasons to be optimistic, there were clear blue skies, light wind, calm seas and we were armed with the freshest bait anyone could ask for.  As we headed north past Government Cut, signs of life were everywhere.  Birds hovered over schools of bait, flying fish took to the air as we passed, and even a free jumping sailfish playfully danced for us in an amazing acrobatic display. Finally we had arrived at the location. We were about 3 miles (4.8KM) offshore in about 150 feet (45M) of water, when we began setting our lines. We were using a drum line setup. First the baited hook and line went in followed by a 35 pound weight and lastly the buoy.  The students stepped up one by one to deploy the lines, after all why not get the youngest and strongest involved first.  We placed our lines one by one, a line of golden Sargassum Seaweed guided our path like our own yellow brick road.  As the team was deploying buoy number nine the Cap called down from the flybridge.  We had a shark already on the number eight buoy.  The tone was set for the day.  There indeed was a shark, a beautiful female sandbar shark golden brown in color and about 7 feet long.  Everyone got to work. The students and the UM team worked with the speed and efficiency of a Nascar pit crew, measuring, recording data, taking samples and finally implanting a spaghetti tag.  In just a few moments the shark was safely off on her way.  The specialized circle hook, designed to catch in the jaw of the shark, did its job as usual and the shark with a powerful sweep of her tail splashed the team at the boat’s stern as she swam off.  We barely had time to high five and celebrate when the Cap yelled down again, “buoy number six!”  Off we went.  This time it was a large bull shark, a powerful stubby nosed dark grey boy 7.5 feet (2.3 m) long.  This was what we were looking for, a perfect candidate for a sonic tag.  This time only the RJD team worked on the shark.  The tag about the size of a thumb drive was implanted in the shark’s abdominal cavity, and after a few stitches he was on his way.  This shark was going to be the first specimen of a new research project studying the movement of local populations of bull sharks.  We told the RJD team we would be interested in adopting this shark through their adoption program and naming him Gulliver, so we could all watch Gullivers’ travels.

The learning opportunities and cross curricular ties would be enriching for Gulliver Schools.  Our day continued at the same frantic pace it began with. Shark after shark was brought onto the boat, another male bull shark, and six more female sandbar sharks all about the same size were caught.   Each of these sharks displayed tooth rakes on their heads and sides, the tell-tale signs of mating.  These bite marks are the result of sort of a shark embrace and the female is anatomically prepared for this with her extra thick skin. What a day!  Muscles were sore, skin was sunburned, gallons of water had been consumed, eight sharks tagged and safely released. The day could get no better, then it did. As we began retrieving the last of the setups, one had a heavy shark on the line.  As we got the shark closer we could believe our eyes.  It was a very large great hammerhead shark.  The whole boat exploded into action.  Hammerhead Sharks are particularly sensitive to stress so this shark had to be tagged quickly. Members of the RJD team grabbed hold of the sharks’ body after a safety lasso was secured and the Gulliver team grabbed on to the RJD Team to keep them from going overboard.  One member of the RJD team got in the water with his GO Pro and recorded the event.  It was controlled mayhem.  This shark was to be satellite tagged.  The tag was quickly affixed to the dorsal fin of the shark and measurements were taken.  The Cap yelled down from the bridge, “My boat is 13 feet across the stern.”  We could all see the shark was longer!  “Ninety three centimeters across her head from eye to eye” someone yelled out.  “Over three feet wide, and her dorsal fin is almost as tall!”  We were all amazed!  After a few minutes she was ready to go.  Pat from the RJD Team was already in the water. He swam her off and gave her a little push, she faded from our view into the cobalt blue water and our experience with the great ocean predator was over.  We had accomplished our mission.  On the way back to the dock we reflected on our day.  Eleventh grader Niles Miller called the day “Epic!” Miriam Vizoso claimed, “What an amazing day for the students!” Jasmin Thernhurr said, “This was a once in a lifetime experience.”  Freshman Paula Ceballos gushed, “Best field trip ever Mr. Gisonni.”  I could not have agreed more.


Shark Tagging with Maritime Academy

by Jacob Jerome, RJD student

Last Sunday the RJD crew had a VERY exciting and successful day of shark tagging with citizen scientists off the coast of Miami. We left the dock on Key Biscayne early Sunday morning and headed for the waters off Miami Beach. Blessed with calm seas and beautiful weather, we set out our first ten drumlines and waited to see what we were going to get.
After the short one hour soak time, we headed to the first line and started pulling. On just our second line there was tension on the monofilament and we knew that we were in for a great day. As we were pulling in the shark, we heard Captain Eric shout from above “Hammerhead!” With total excitement, everyone got into their places as we brought the shark up to the boat. Knowing that hammerhead sharks are more sensitive, we completed our workup in record time while still being able to attach a satellite tag! With the satellite tag pinging the shark’s location every time it surfaces, we will be able to learn more about where the shark is going and hopefully help to protect the areas that sharks like to hang out. After watching the beautiful shark swim off, we headed to line number three.

 A great hammerhead shark is secured next to the boat.

A great hammerhead shark is secured next to the boat.

With complete dismay, we pulled up the third line to find another great hammerhead! Working even faster, we collected any data that we could and then released our second shark of the day in great condition.

Our luck didn’t end there. Just two lines later, we pulled up a large dusky shark. Nearly everyone on the boat had never seen this species before and we were all very excited to begin our work. After holding down the feisty shark long enough to collect our data, we released the large male in great condition. With three sharks on our first six lines everyone was pumped to see what the rest of the day would bring!

Rounding out our first ten lines we managed to catch two more sharks, a tiger and lemon. A satellite tag was placed on the juvenile tiger shark so we can track where sharks at this age are hanging out. With a busy day so far, we decided to only set out five more drumlines so we could get back to the dock at a reasonable time. Already averaging one shark for every two lines, we were very excited to see what these last five would produce.

A fin-mounted satellite tag on a juvenile tiger shark.

A fin-mounted satellite tag on a juvenile tiger shark.

Of the five lines we set, four of them had sharks! What was even more incredible was the species diversity and rarity of those sharks. We caught two more great hammerheads, a dusky and nurse shark. While we often sample from powerful nurse sharks, it is rare for us to get hammerheads, let alone four in one day! The dusky sharks that we collected data from were also a rarity for the lab. In the history of the lab we have only collected data from two other dusky sharks. Meaning in one day we doubled our sample size for this species!

It’s safe to say that last Sunday was one of the best trips I’ve ever been on! In just fifteen lines we were able to catch nine sharks of five species. Our team would like to thank the citizen scientists that joined us for their hard work pulling in lines and helping us in our data collection.

A large lemon shark is secured while blood is being drawn.

A large lemon shark is secured while blood is being drawn.