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Shark tagging with Firebrand Events

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By Julia Whidden, SRC Intern

On Monday, March 14th, the SRC Crew went to sea with assistance from Firebrand events. We fished the shallow waters (~ 10 feet deep) of Safety Valve, an area of sand flats and tidal channels that connect Biscayne Bay to the Atlantic Ocean. Research dates the formation of this bay to between 5,000 and 2,400 years ago, while it was only “discovered” to European forces by the Spanish explorer Juan Ponce de Léon in 1513. It was around this time that explorers and fishers of the sea began to record their varied superstitions. Their expeditions were plagued by many sources, including – but not limited to: garlic, actual plagues, the number 13, and bananas.

An aerial photo of Safety Valve, the region of shallow sand flats and tidal channels that delimit the entrance of the Atlantic Ocean to Biscayne Bay. The SRC team fishes this spot often.

An aerial photo of Safety Valve, the region of shallow sand flats and tidal channels that delimit the entrance of the Atlantic Ocean to Biscayne Bay. The SRC team fishes this spot often.

While the choppy water kept us from the high seas, and our fishing was for research purposes and not sustenance, we managed to fall victim to the old sailor’s curse of the bananas. Believe it or not, SRC and Diver’s Paradise boat Captains strictly enforce the “NO BANANAS” rule. Not only are they forbidden in the contract that our passengers sign, but even mention of them by SRC grad student and banana-enthusiast Pat Goebel is usually enough to get the team riled up. On this fateful Monday, SRC crew discovered – after pulling up the first set of 10 lines empty – that each of the nearly 20 Firebrand passengers had been packed lunches with… (cue dramatic music)… bananas. Diver’s Paradise Captain Eric Cartaya took matters into his own hands and collected the remaining evil fruit from a very confused set of passengers. The bananas were piled on the bait-cutting table, smashed to bits, and swiftly tossed out to sea. The passengers remained confused. After explaining to them some of the varied and nonsensical origin stories of the banana curse, we had made it back to buoy 1 of the second set of lines.

Diver’s Paradise Captain Eric Cartaya rids our boat of the evil bananas.

Diver’s Paradise Captain Eric Cartaya rids our boat of the evil bananas.

Lo and behold, our luck changed and we caught a 1.52 m blacktip shark! This male blacktip was very freshly caught, having only been on the line for 8 minutes. We conducted a full work-up with assistance from our Firebrand crew, including measuring, tagging, fin clipping, and reflex testing. After releasing this blacktip in great condition, we sped off towards our next buoy.

SRC crew Robbie Roemer and Julia Whidden release our first catch of the day, a male blacktip shark.

SRC crew Robbie Roemer and Julia Whidden release our first catch of the day, a male blacktip shark.

We pulled up another 8 empty lines before feeling any tension on our last line of the second set. This time, we had caught a 2.3 m male nurse shark. The most interesting characteristic of this male nurse was its recently mated claspers. Claspers are the external sexual organs of male elasmobranchs (sharks, skates and rays), and have friendly features such as hooks and barbs that are used to hold onto the female during copulation. Males may only copulate successfully with a female once it has reached sexual maturity, which is physically manifested as fully calcified (hardened) claspers. In male nurse sharks, sexual maturity is reached when the total body length is around 2.1 m. This male nurse shark that we processed showed signs of having recently copulated, which appear as fresh mating scars on the male’s claspers. This type of sexual maturity data is useful in identifying the breeding requirements, including seasonality and habitat preferences, of local shark populations. After finishing the workup, the SRC team released the nurse shark in great condition.

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The mating scars seen on our second catch of the day, a male nurse shark.

Our final 10 lines of the day proved fruitless, but the SRC crew and Firebrand passengers felt lucky to have caught even 2 sharks considering the bad luck that started their day. While it’s difficult to know precisely which life lessons were learned by passengers and crew of the boat, ie. don’t get between a boat Captain and a banana, I personally took this opportunity to learn “The Bananas Aboard Repentance Prayer,” in case I ever need to appeel to the shark gods again.

The Bananas Aboard Repentance Prayer

Oh great Konpira
please, hear my plea
I am sorry for my mistake
A banana I brought to sea

it was an honest gesture
a noble means of nutrition
I had no ill intent
I brought fruit of my own volition

Please forgive my idiocy
I meant my friends no harm
We just want to go fishing
and go home with a sore arm

We beg of you to release the curse
upon which I have brought
In your honor I consume these bananas
a sacrifice all for nought!

Sources:
http://miamifishing.com/bananas-and-fishing-boats
http://www.discoverbiscaynebay.org/history-and-ecology.htm
https://upload.wikimedia.org/wikipedia/commons/6/6f/Biscayne_Bay_Safety_Valve.png

National Geographic Filming: Day 1

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By Julia Whidden, SRC Intern

On February 15th, a crew of 8 SRC members and 7 National Geographic filmmakers merged together for a 3-day tagging excursion in search of the Ferraris of the ocean: the great hammerhead shark (Sphyrna mokarran). With cloudy skies and a slim chance of rain, we made brief introductions and set off together from Diver’s Paradise at Crandon marina to the shallow waters of Cape Florida Channel. Spoiler alert: we got skunked.

SRC Intern Shannon Moorehead being filmed recording data.

SRC Intern Shannon Moorehead being filmed recording data.

While the etiology of the fishing term ‘skunked’ is debatable, most anglers can agree that catching no fish – oh, the irony – stinks. It was a first for many of the SRC interns on the boat that day, including myself, but we remained hopeful as we pulled in each of the 45 lines set that this next line would be the one. We baited our circle hooks with bonito (of the tuna family Scombridae) and barracuda (of the barracuda family Sphyraenidae, and the 1977 hit by Heart), and had several lines come up with the bait nearly intact! The sharks just weren’t ready for their on-screen close-up. The film crew used their free time to record us doing the less glamorous side of shark fishing, including cutting bait, organizing tools in our beloved “FatMax” toolbox, setting and retrieving (empty) drumlines, recording data, performing interpretive shark dances, and the fishing highlight of our day: retrieving the fish traps. At the beginning of most shark trips, we set out 2 baited fish traps near our fishing site to investigate the species assemblage of the area, or what fish our sharks may be feeding on. Today we baited both traps with cross-hatched jack, which we cut into to release juices and draw in nearby fish. After soaking for nearly 5 hours, we retrieved the 2 traps to find a combined 4 fish, including 2 white grunts, a juvenile redtail parrotfish, and a Houdini fish that escaped my slippery grip before we could identify it. From both a fishing and filming perspective, the day ended quite anticlimactically. However, we took the time to get to know the film crew, and the film crew took some time to learn about obscure and underappreciated sharks, thanks to SRC Intern Rachel Skubel having brought along her copy of “Sharks of the World”. While sound engineer Eddy’s newfound knowledge of lanternsharks did not prove useful over the rest of the trips, the chance to become friends with the film crew on our quiet first day was really valuable. Besides the obvious benefit of knowing someone before you end up in a confined space with them and a shark, talking to the film crew gave me the chance to ask questions about the holy grail of nature journalism that is National Geographic. Having grown up with the magazine being a staple of my family’s coffee table selection, I was beyond thrilled to be even somewhat involved with them, and mentally checked off “do work with Nat Geo” from my bucket list. As it turns out, getting skunked wasn’t so bad after all.

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Film crew sound engineer Eddy reading about the sharks we weren’t catching in “Sharks of the World”.

At the end of the day, we had collected data about the day’s environmental variables, including water temperature, salinity, and dissolved oxygen. Even though we weren’t able to add to it with any shark data, the saying in science goes that “no data is still data”. This means that despite not having caught any sharks in the Cape Florida Channel today, we can still learn something about why the sharks weren’t there or why we weren’t able to catch them, possibly relating to seasonal movement patterns, the day’s weather, species-specific behaviors, feeding and habitat requirements, fishing location, and a variety of other factors. Our crew remained optimistic through 45 lines of empty hooks that tomorrow would bring more action, and that today was the calm before the storm! Spoiler alert: we were right.

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One of the two white grunts that we caught in our fish traps, looking like he’s not happy about his impending physical exam.

Shark Tagging with South Broward High School

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By Grace Roskar, SRC Intern

The morning of February 12th, 2016 was a beautiful day for the SRC team, the Diver’s Paradise captain and crew, and students of South Broward High School to set out for a day of shark tagging. We also had two citizen scientists on board, ten-year-old Tristan and his father Jivan from North Carolina. South Broward has been a participating school group of SRC for several years, and after enduring traffic from the Miami Boat Show, the group was anxious to board the boat and embark on a day of science, sharks, and sunshine.

The waters were calm as we motored out to a certain location among the group of shallow tidal flats known as the Safety Valve in Biscayne Bay. Drumlines were prepared with tuna or jack for bait and set out to let soak for an hour. Many of the South Broward students had been on an SRC trip before, but they were still eager to listen to trip leader Jake’s demonstration of the workup process for a shark. They were already knowledgeable about different shark species, as well as how they breathe by swimming to actively force water through their mouths and over their gills, allowing for the uptake of oxygen, in a process known as ram ventilation.

Trip leader and SRC Master’s student Jake tells students about the workup process for a shark and uses Sharky, the stuffed shark, to demonstrate the procedures

Trip leader and SRC Master’s student Jake tells students about the workup process for a shark and uses Sharky, the stuffed shark, to demonstrate the procedures

After an hour had passed, we set out to retrieve the first set of ten drumlines. On one line was a blacknose shark, which is a smaller species that SRC does not encounter often. This blacknose was a male and about 119 centimeters long, or a little shorter than 4 feet. Due to its small size, Jake and Rock brought the shark directly onto the back of the boat instead of setting up our large platform, and it was safely secured on deck. Next, our citizen scientists and South Broward students assisted the SRC team with a nictitating membrane test to test the shark’s stress levels, several length measurements, taking a sample of the dorsal fin, and inserting a dart tag into the shark’s dorsal fin. Rock took morphological measurements and Hannah swiftly drew blood from the caudal vein of the shark, to be used for several different measurements such as glucose and hematocrit levels, which is valuable data for Jake’s ongoing Master’s thesis. After a quick workup, students were able to take a few moments to touch the shark and feel its dermal denticles, which are scales that are basically modified teeth, as dermal denticles means “small skin teeth.”

A South Broward student quickly pumps seawater into the shark’s eye to watch for its ‘eyelid’, called a nictitating membrane, to pop up. This reflex is a possible measure of stress levels in the animal.

A South Broward student quickly pumps seawater into the shark’s eye to watch for its ‘eyelid’, called a nictitating membrane, to pop up. This reflex is a possible measure of stress levels in the animal.

The blacknose shark was quickly and safely released, and we moved on to set out to retrieve the rest of the drumlines. There were no more sharks on the lines, so they were set out for two more sets. While pulling up one line, Jake felt tension for a moment, thinking it could be a shark, but then the line was released and the tension dissipated. It is possible there was a shark on the line but was not hooked completely and was able to get away. Even with some South Broward students choreographing their own “shark dance” in hopes of good luck, after thirty lines, we had only caught the one shark. With hopes still high, we had time to set out five more lines, but trip leader Jake and Captain Eric decided to try a new spot. We motored closer to Stiltsville, a group of houses built on stilts in a different part of the general area of the Safety Valve. We quickly set out five more baited drumlines and let them soak for about forty-five minutes. To our delight, another blacknose was hooked! It was carefully brought onto the back deck of the boat and secured by Jake and Rock. Our trip guests helped again with the nictitating membrane test, measuring the shark, taking a fin clip, and tagging the shark. Hannah was able to successfully draw blood once more and I helped with morphological measurements, including the span of the shark, clasper measurements, and taking pictures of its fins to be digitized for scale to see how sharks grow over time.

Tristan and Jivan, our citizen scientists for the day, help insert a spaghetti tag into the sharks dorsal fin.

Tristan and Jivan, our citizen scientists for the day, help insert a spaghetti tag into the sharks dorsal fin.

After thirty-five lines, the team and students were elated and grateful to have caught two blacknose sharks, which is a more rare occasion on the SRC boat! With beautiful weather all day, it was overall an exciting day on the water with South Broward High School and our citizen scientists. Although many South Broward students had been on a trip with us before, their excitement to learn about and see these apex predators never faltered. We were honored to have Tristan and Jivan onboard with us and were grateful for their help throughout the day. The SRC team gathered valuable data from the two blacknose sharks and we hope that South Broward will come out with us again soon!

 

 

 

Shark Tagging with Hialeah High School

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By Casey Dresbach, SRC Intern

On the fairly windy and overcast morning of December 3rd, the SRC team and honorary audience members set sail on yet another successful venture. The SRC team and I met at Crandon Park at 8 AM, along with high school students from Hialeah High School, and a very special guest, a Canadian documentary filmmaker. As we boarded the boat, the skies began to clear up and ensured a day filled with adventure.

Catherine Macdonald, the trip leader for the day, and Jake Jerome, my fellow intern, began to speak to the students about our fishing methods and why we use such specific gear. The two briefed the students on why SRC does what we do and how each and every one of them were about to help in collecting crucial data which impacts both shark research and management. While the explanation took place, I, along with the rest of the team began to set up the gear, bait the hooks, and deploy the drums. This was repeated three times, a total of 30 deployed drums for the day. After the first set of ten, we held tight to let the bait soak in the water for about an hour. Upon waiting, I got to speak with a couple of the students and their very enthusiastic teacher. For some students, it was their first time seeing sharks, let alone being aboard a boat! Having such an avid educator on board made all the difference; the energy was wonderful and not only did the team respond, but the sharks were pretty responsive too! Our first cartilaginous friend hooked onto line four to join our educational soirée. The beautiful male Black Tip came aboard at around 170 cm, about five and a half feet long. To avoid setting up the platform in such rough seas, we landed the shark onto the boat. Little did we know that this little guy would foreshadow the rest of our catches… all to whom were in fact Black Tips! I’m honored to say I took part in such a remarkable set of catches! Teams of four students were set up and each one got to take part in the four primal procedures: nictitating the eye membrane, measuring the shark, taking a fin clip sample, and of course, tagging the shark.

A student conducts a reflex test on the shark’s eye with a stream of ocean water, checking for its ‘eyelid’ called a nictitating membrane. This reflex is being tested as a possible measure of stress levels.

A student conducts a reflex test on the shark’s eye with a stream of ocean water, checking for its ‘eyelid’ called a nictitating membrane. This reflex is being tested as a possible measure of stress levels.

The rest of the day seemed to go by fairly quick; five more sharks were caught throughout the next several hours. We landed a male Black Tip at 157 centimeters (a little over five feet), followed by a male Black Tip at 159 centimeters (a little over five feet), yet another male at 170 centimeters (about five and a half feet), and two female: one with a total length of 170 cm and another at 173 centimeters (almost 6 feet!). The team aided the participants in their tasks, snapped photos of each to get accurate measurements to scale, and drew blood from each shark, which that was taken to the back of the boat and examined by my fellow intern, Stephen Cain. Eager students head back to join him and soak in his masterly shark blood handling. Catch after catch I was able to see the spark in each and every one of the students. In being apart of such an incredible Shark Research Program, I have learned to appreciate the most satisfying recognition: inspiring high school students to take in new knowledge.

A student assists intern, Casey Dresbach, with measurements of the shark.

A student assists intern, Casey Dresbach, with measurements of the shark.

Honorary Hialeah High School’s biology teacher helps pull in a line, with Blacktip hooked on!

Honorary Hialeah High School’s biology teacher helps pull in a line, with Blacktip hooked on!

Overall, we had an extraordinary day on the sea with Hialeah High School and the Canadian documentary team, in spite of the choppy waters. After catching a record six Black Tips, I can only presume that everyone on board left feeling satisfied and content with the day. The SRC team was able to gain valuable data from our catches and workups. The trip was made best because of the enthusiasm instilled in all of the students, thank you for your hard work and energy! We only hope you continue to instill your passion in the future; it truly is remarkable. Hope to you again soon!

Shark Tagging with Our Lady of Lourdes Acadamy

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By Christopher Brown, RJD Intern

As dawn broke on Saturday, November 7, 2015, eight sharky RSMAS students and one fearless lab manager awoke to the call of the sea. The RJD team assembled at Diver’s Paradise in Crandon Marina at 8:00am to begin loading the boat with the shark-friendly fishing gear that is utilized to conduct tagging and sampling procedures. Everyone was in a great mood because the forecast for the day called for perfect fishing weather. Once the high school students from Our Lady of Lourdes Academy arrived, brief introductions were made, and the crew set out for an eventful day of shark tagging!

As Captain Nick Perni set course for fishing grounds south of Key Biscayne, and the RJD crewmembers cut bait and prepared the drumlines for deployment, lab manager Christian Pankow briefed the high school group on how the fishing equipment is deployed and retrieved throughout an entire day of fieldwork. Even though Our Lady of Lourdes Academy are old hands at tagging and sampling procedures, they were surprised to learn that fish traps are now being utilized by the RJD team to investigate fish morphologies and population assemblages associated with the presence or absence of shark populations. The two fish traps were deployed south of Stiltsville, a group of wood stilt houses positioned on the edge of Biscayne Bay along the sand banks of the Safety Valve. Then, after watching RJD Intern Samantha Owen demonstrate how to safely and properly cast out the baited circle hook and line, Our Lady of Lourdes Academy students helped deploy the remaining nine drumlines.

While the lines “soaked” for an hour, the students assisted with taking environmental measurements, including the salinity and dissolved oxygen content of the surrounding ocean water. Lab manager Christian Pankow gave another briefing to Our Lady of Lourdes Academy to prepare them for the participatory day of shark research, which would include fin clips, measuring, and collecting vital tissue samples and data. However, the briefing was cut short when a blacktip shark was spotted breaching around the first research buoy, which meant a shark was on the line! The first group of students assembled to assist with data collection as the RJD team sprung into action. The 1.46 meter (4.79 ft) blacktip shark, which was one of the smallest sharks of the day, was swiftly and carefully secured onto the stern of the boat and the water pumped was inserted into the shark’s mouth. RJD graduate student Jake Jerome collected a blood sample from the caudal vein and Our Lady of Lourdes Academy students assisted with taking morphological measurements and inserting a dart tag into the shark’s dorsal fin. After completing a successful workup, the blacktip shark was released back into the water in great condition. The breaching blacktip shark was an amazing sight to see and was only the beginning of a fantastic day of shark tagging.

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The largest shark of the day was a 2.00 meter (6.56 ft) great hammerhead that was caught while pulling in the second round of drumlines. Great hammerhead sharks are easily stressed and become quite delicate when kept on the line for an extended period of time, so the students watched from the top deck as the RJD team worked up the shark in less than four minutes. RJD graduate student Jake Jerome was able to collect a blood sample from the caudal vein of the great hammerhead for his ongoing Masters’ research, and the crew worked efficiently enough to conduct an entire workup procedure before the great hammerhead needed to be returned to the water.

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In total, the RJD team landed a 2.00 meter (6.56 ft) great hammerhead shark, a 1.67 meter (5.47 ft) nurse shark, a 1.25 meter (4.10 ft) black nose shark, and six blacktip sharks ranging from 1.18-1.71 meters (3.87-5.61 ft). Each shark was swiftly and carefully brought to the boat and secured on the platform for a brief sampling and tagging procedure. It is safe to say that Our Lady of Lourdes Academy students are now well practiced in tagging, sampling, and morphological measurement techniques. One of the procedures performed by the students included the nictitating membrane reflex test. The nictitating membrane is a clear, inner eyelid that protects the eye of a shark during feeding events. The reflex of the nictitating membrane is one visual factor that can be used to determine the stress impairment of sharks.

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After the remaining drumlines were brought on board, the crew finished the day by checking the fish traps set earlier in the morning. A series of morphological measurements and images was taken of each of the several bony fish caught in the fish traps for future analysis. Overall, the RJD team had a fantastic day out on the water with Our Lady of Lourdes Academy. We hope they enjoyed the opportunity to participate in a day filled with exceptional scientific research and education, and we cannot wait for them to join us again on future shark tagging trips.

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Shark Tagging With Palmer Trinity High School

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By Melissa Soto, RJD Intern

It was a warm November morning as the students from Palmer Trinity high school made their way onto the boat. This was my first trip of the semester so I was just as eager as they were to see sharks. After placing all the gear onto the boat, RJD and our guests were off to tag some sharks.

A Palmer Trinity student kissing the bait for luck.

A Palmer Trinity student kissing the bait for luck.

Our trip leader for the day was Christian Pankow, who kindly greeted everyone on board and continued by explaining the work up the team does on the sharks. After a calm thirty-minute boat ride we started deploying the 10 drumlines around Stiltsville, off of Key Biscayne.

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A student carefully released a drumline into the water.

After waiting an hour, we started to check the drumlines and after a three tries, we found ourselves a shark. A female black tip was safely worked up on the platform. The students broke up into groups of five and began the work up consisting of fin clip, tagging, measuring and two nictitating membrane tests. This beautiful shark was 1.65 meters and healthy. Once the work up was completed, the shark was released.

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Students and the RJD crew quickly work up the blacktip.

We continued to check and redeploy the drumlines but they were no sharks. Our second and third sets of deployments were a success. Three more black tips with lengths of 1.67 meters, 1.58 meters, 1.62 meters and a 2.35-meter nurse shark were pulled up. These four female sharks were worked up with the help of the students and RJD.

Another bait kiss for luck.

Another bait kiss for luck.

After pulling up the rest of the drumlines we made our way back to marina and took some group photos. Palmer Trinity was a great group of enthusiastic children and chaperones. We hope that they come out for another trip soon.

 

Shark Tagging with South Broward High School

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By Dana Tricarico, RJD Intern

Friday October 23, 2015 was officially my second trip as an RJD intern. Needless to say, I was extremely excited to get the day started and to become more familiar with all the jobs on board. It was a beautiful morning for some shark tagging as the team met at the University of Miami’s RSMAS campus to begin the transport of the gear to the dock at Diver’s Paradise. Upon arrival at the dock, we met the group of South Broward High School students, specifically from aspiring marine scientists in the Marine Magnet program, better known as the South Broward “Reef Dogs.”  Many of these students were also part of the high school’s Shark Club and/or were RJD citizen science veterans. We also had local volunteers and two science communicators on board as well to help in our efforts and to document the day!

At the start of the day, the team makes the final preparations before the fish traps and drumlins are deployed.

At the start of the day, the team makes the final preparations before the fish traps and drumlins are deployed.

Our trip leader for the day was David Shiffman, who explained to the group the benefits of our gear and how our team deploys it. While David explained this, our team got the gear ready as the boat headed out to our destination.  Despite the sunny skies, the wind was strong, so the decision was made to tag in shallower areas within Biscayne Bay. Once all 10 drum lines were placed into the water, Eric Cartaya, captain of our ship, gave a brief history of the area while we waiting for the bait to soak in the water. We learned that the area we chose to tag in that day was right near Soldier Key, the northernmost of the Florida Keys. He also explained that although Key Biscayne is further north, it is not a true key because it is made of sand, and not limestone.

After a full hour passed from the deployment of the first drumline, we began pulling up each of the drumlines with the help of our citizen scientists on board. The first set of 10 drumlines was pulled without any sharks, but we definitely did not lose hope. We continued to place them back in and keep our spirits high with several group shark dances! They must have worked because after we pulled up almost half of the second set up drumlines, we got our first shark- a nurse shark! This was by far the largest nurse shark I had ever seen as it was well over 2 meters. The coloration was extremely interesting because it was so dark.

A student assists with taking a series of morphological measurements of a nurse shark.

A student assists with taking a series of morphological measurements of a nurse shark.

The South Broward High School students and other volunteers broke into four different teams. Each person within the team had a job which they helped us with once we pulled the shark onto the platform. These jobs routinely include measuring the shark, taking a fin clip and tagging the shark with something we call a “spaghetti tag.” For other species of sharks, we also have the volunteers help us with a stress test by checking the presence of the nictitating membrane on the eye with a squirt of salt water. All of the data collected through these jobs is used in ongoing research projects in the lab, in order to protect these species and to learn more about them. Additionally, volunteers were able to watch RJD intern Laurel Zaima take photos of some of the fins of the shark for morphology information, and were also able to watch intern Jake Jerome take blood from the underside of the tail for his ongoing Master’s research.

Fin Clip

A student takes a finclip, a small cartilage sample that will help reveal long-term toxicology and dietary patterns. Trip leader David Shiffman, and RJD Graduate intern Emily Nelson assists in the process.

The day moved quickly with small rain showers every once in a while to help and cool us off. Later on in the day we were able to tag another large nurse shark with similar coloration to the first we found. David, who has seen a great deal of nurse sharks throughout his research, said that the two nurse sharks we saw were two of the darkest nurse sharks he had ever seen!  From my experience, sometimes, people tend to overlook nurse sharks and do not realize how incredible they are. As someone who personally has now had to secure a nurse shark in order to get the necessary data collected, the sheer strength of Nurse Sharks is impressive in itself. I was very lucky to be able to work with both of these sharks, and to do so with a very enthusiastic group of volunteers! Not only that, but I was able to learn from experienced RJD interns who made me increasingly more confident in all the jobs onboard, so I can be even more knowledgeable next time!

It was a great day for some shark tagging. Thanks to South Broward High School for all of your help!

It was a great day for some shark tagging. Thanks to South Broward High School for all of your help!

 

Shark Tagging with Pine Crest School

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By William Evans, RJD Intern

I woke up on Thursday morning and saw that it was slightly overcast and drizzling. For more people, this would be a sign of a gloomy day inside but for me and the rest of the RJD crew, it was the perfect set up for a day of shark tagging. The crew met at Crandon Park at 8 AM, along with high school students from Pine Crest School in Fort Lauderdale. As we boarded the boat, reviewed some boat safety and pulled out from the marina, the skies began to clear up and the sun was shining.

Our trip leader for the day, Christian Pankow, began to speak to the students about our fishing methods and why we use the specific gear that we do. While Christian was talking, the rest of the team began to set up the gear, bait the hooks, and deploy the drums. After the 10th drum was deployed, we waited to let the bait soak in the water and allow time for sharks to get on the hooks. While we were waiting, Shannon Moorhead, an undergraduate student at UM, and I saw a blacktip breach on the 6th drum! We knew it was a good sign for how the rest of the day was going to go. Because of our sighting, we went to the 6th drum first and sure enough, there was a blacktip shark on the line. That was only 1 of 4 blacktips from that days trip. Of the four, the last blacktip that we pulled in was 1.92 meters, slightly over 6 feet, which Christian said was the “first or second largest blacktip” that he’s ever seen!

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A closeup image of a blacktip eye and ampullae of lorenzini.

The Pine Crest students were able to interact with each shark by assisting the team in collecting data. The student tasks were checking the presence of the nictitating membrane on the eye with a squirt of water, measuring the shark, taking a fin clip, and tagging the shark. These opportunities allow students to not only interact with sharks but to participate in meaningful research and will hopefully light a spark in them to pursue science or at least be more knowledgeable about sharks importance to the ocean ecosystem. It was also beneficial to the students to be able to witness another graduate student, Robbie Roemer, be able to collect blood samples from all of the blacktip sharks.

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The RJD team secures the shark as graduate intern, Hannah Calich, assists a Pine Crest student in tagging the blacktip shark.

Towards the end of the day, we also caught a small, adult blacknose shark in addition to the 4 blacktips that we caught before.  Because of its size, it was placed on the deck for the work up and the students on board were able to get a chance to see the differences between the blacktips we caught before and this new species. We made it back to the dock to unload and clean the gear for the next trip going out the following day. Aside from all of the sharks, not having to remove the drums from the boat was my favorite part of the day! Although it was an exhausting day, that was the most amount of blacktips that I have personally seen on a trip and even though they are not my favorite shark, they are still beautiful animals. Every tagging trip makes me more excited than the next because I come on the boat more equipped with knowledge than the time before!

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Trip Leader, Christian Pankow, and undergraduate intern, Casey Dresbach, secure this blacknose shark as graduate intern, Robbie Roemer, draws blood for analysis.

 

 

 

Shark Tagging with Westminster Christian School

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By Hannah Calich, RJD Graduate Student

Last Friday the RJD team was joined by the fabulous students and teachers from Westminster Christian School for another day of shark tagging!

The Westminster students, teachers, and the RJD team after a great day on the water

The Westminster students, teachers, and the RJD team after a great day on the water

The RJD team met at Crandon Marina at 8 am to begin loading up Divers Paradise. Despite the hurricane over the Bahamas, Miami’s coastal waters were calm and the weather was great, so we were eager to get out on the water. Once everyone was on the boat the RJD team introduced themselves, our trip leader, Emily Nelson gave everyone a briefing, and we set off!

Once we got to the site, the RJD team deployed a baited fish trap as part of a new project we’re working on to learn more about the fish communities at our tagging sites. Once the trap was deployed we set 10 drumlines, took some environmental data, and had some lunch while we let the lines soak. After the hour-long soak we began checking our lines. Our first line came up empty, but when we got to drum # 2 we felt a familiar tug on the line and everyone sprang into action. Our first shark of the day was a 171 cm male blacktip shark!

A Westminster student gives the bait a kiss for good luck!

A Westminster student gives the bait a kiss for good luck!

Once we tagged and released him we headed over to drum # 3 where once again we felt a familiar tug on the line. Our second shark of the day was a 174 cm female blacktip shark! What was particularly interesting about this girl was that she was a recapture! We checked our records and determined that we originally tagged her back on November 1st, 2013! Back in 2013 she was 169 cm and has grown to 174 cm since then. We get really excited about recaptures because they are relatively rare and give us a lot of interesting data about how these animals are growing, where they are living, and what they are eating!

A Westminster student helping collect a fin clip from one of the blacktips

A Westminster student helping collect a fin clip from one of the blacktips

Once we re-tagged and released her we went to drum # 4, where once again there was a shark on the line! On drum # 4 we caught another 174 cm female blacktip! She had only been on the line for a few minutes so we decided to surgically implant an acoustic tag in her abdomen as part of our Urban Shark Project, which is studying how sharks use highly urbanized environments.

Once she was tagged and released we went back to checking and rebaiting our lines. Unfortunately, the next 16 lines came up empty. However, something was clearly eating our bait and since the first few lines had been so busy we knew it was only a matter of time until we caught another shark, so we decided to set 5 more lines.

While we were waiting for those lines to soak we decided to pull up our fish trap and work-up the fish we caught. We ended up catching about 25 fish from approximately 6 species! Once the fish trap was back on the boat we went to check on our drumlines and found that we’d caught one last shark! This time we had caught a large (240 cm) male nurse shark! The RJD team secured him while the students went to work collecting data. Within a few minutes the workup was complete and he was on his way again.

RJD intern Julia Whidden takes measurements of a fish caught in our fish trap

RJD intern Julia Whidden takes measurements of a fish caught in our fish trap

In the end it was a very successful day because we caught 4 sharks! We caught 3 similarly sized blacktips (one of which was a recapture!) and a large male nurse shark. In addition to doing our usual work-up we also deployed an acoustic tag and gained new data on the local fish communities! Thanks again for all your hard work Westminster, it is always a pleasure to go out with you guys. I can’t wait until the next trip!

Our last shark of the day, a 240 cm male nurse shark!

Our last shark of the day, a 240 cm male nurse shark!

 

Shark Tagging With Steve Brodie Charter

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By Alison Enchelmaier, RJD Intern

Friday morning couldn’t come fast enough. It felt like forever since I had been on a tagging trip and I was chomping at the bit to get started. The crew arrived an hour early to load gear and everyone seemed to be in a genial mood as we hauled drumlines and bait. Today our new intern, Julia Whidden, was joining us for her first trip! Just as we were loading up, we were joined by our group of UM citizen scientists.

Dr. Neil Hammerschlag explaining RJD’s shark workup procedure

Dr. Neil Hammerschlag explaining RJD’s shark workup procedure

We headed out to Stiltsville, a series of stilt houses that reside offshore in Biscayne Bay, and began to set our gear. We added a new procedure to our protocol on this trip, fish traps. Our fish traps are large, square, portable structures made of mesh meant to catch fish without a rod and reel. We use these traps to see what fish live in the areas where we catch sharks. We placed two fish traps into the water and let them soak while we fished for sharks. After the traps were released, we set our drumlines into the water and let them soak. While we waited, Dr. Hammerschlag explained the importance of shark research and conservation and our citizen scientists learned about the tasks they would be participating in on the trip.

The RJD crew sets up gear

The RJD crew sets up gear

After an hour, we returned to check on our lines. Early in the day, we don’t often get a shark on the first line so imagine our surprise when we caught a shark on our first line, and it was a blacknose to boot! Most blacknose sharks are small; adults can grow to about 4 ft long. We don’t catch them often, so this find was a real treat! There was no time to spare as we had another shark on the second line, this time a 172 cm (~5.6 ft) female blacktip. Our citizen scientists helped the team measure, gather blood and fin samples, and tag the shark before releasing her back into the water. The next shark we encountered was another blacktip, female as well at 163 cm (~5.3 ft).

 

Citizen scientist checks the reflexes of a blacktip shark by squirting water in its eye.

Citizen scientist checks the reflexes of a blacktip shark by squirting water in its eye.

As we pulled in the last line the sound of thunder indicated it was time to head back to shore. On the way back to the dock, we retrieved the fish traps and identified the fish we caught. Between both traps there were five fish in total and three different species of bony fish. The species we caught were planehead filefish, a saucereye porgy, and two lane snappers.

All in all, it was a wonderful day! Thank you to our citizen scientists for joining us on a great trip!