Shark Research – Page 6 – Shark Research & Conservation Program (SRC)

Shark Tagging with Maritime Academy

March 23, 2015/0 Comments/in Ocean News, Shark Research /by aanstett

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.

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.

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.

Shark tagging with the Virginia Aquarium

March 11, 2015/1 Comment/in Shark Research /by aanstett

by Hannah Armstrong, RJD intern

On Friday, February 27^th the RJ Dunlap team set out for what we all anticipated to be a great day of shark research. I was eager to head out into Biscayne Bay, as this was my first trip of the New Year. I had the pleasure of being on a boat with our fearless leader, Christian, as well as Nick, Laurel, Cat and visiting RJD alum, Megan, and an energetic group from the Virginia Aquarium.

During the short, 20-minute boat ride into the bay, we did our usual prep work, including preparing bait, setting up the drum lines, and briefing the citizen scientists on board. Upon arriving at the Safety Valve, a shallow site just off Key Biscayne, we began deploying the drum lines with the help of the guests from the Virginia Aquarium. Everyone was eager to lend a hand and get the day started.

During the hour soak time, Christian gave a detailed explanation of the work up procedure in the event that we had a shark on the line, and spoke about the importance of our research. Little did we know how exciting our day was about to get…

Despite the first six lines coming up empty, we were all startled when our captain Nick shouted, “Look! There’s a shark on seven!” Low and behold, there was a blacktip shark thrashing about, breaching out of the water by our drum line! We quickly motored over, but the hook came loose and the shark darted off into the abyss.

From then on, there was little time for rest or even lunch. The next two hooks also had blacktip sharks on them that we were able to successfully tag and release. Each time a shark was on board, the guests quickly completed their jobs, taking measurements and other samples to be used in ongoing lab research projects.

On the second set of drum lines, we managed to tag and release another three blacktip sharks, measuring in at 162, 167, and 152 centimeters. On the third and final set of drum lines that we set, our team was able to successfully tag and release four more blacktip sharks. Overall, it was a thrilling day of shark research for our team as well as the cooperative citizen scientists from the Virginia Aquarium!

Shark Tagging with Citizen Scientists

March 4, 2015/0 Comments/in Shark Research /by aanstett

by Alison Enchelmeier, RJD student

This past Thursday and Friday, the RJD crew spent two days tagging with a group of citizen scientists. Our guests met us at the boat at 9:00 am and we set off for one of our usual spots, Safety Valve. I’d been on a trip there the previous week and we had caught a variety of sharks, so I was hopeful we would be just as lucky this week. We set out lines and Dr. Hammershlag explained to our guests how we catch sharks, work up sharks, and the research involved for each sample and measurement. After leaving our lines soak for an hour we returned to pull up the first line. Our day began with a nurse shark on line three, but before we could pull it onto the boat it got off the line. The citizen scientists were disheartened by the loss, worried that the lost nurse would be the only shark they would see. Their fears were unfounded as two lines later we caught another nurse. Over the course of the day we remained busy as we caught six more nurse sharks ranging from 2.09 m (6.86 ft) to 2.63m (8.63ft) and one bull shark that came off the line before we could bring it to the boat. With a successful day of seven nurse sharks we returned to Crandon Marina for the evening.

On Friday we decided to fish closer to shore to try and find a different variety of sharks. We set our lines out along Bear Cut and RSMAS and measured water temperature, dissolved oxygen, and salinity while we waited for the lines to soak. All conditions seemed to be in our favor as the very first line we pulled up wriggled with the weight of a shark. As the line reeled in we held our breath, was it a nurse shark or something else? As the fin broke the surface we had our answer, a bull shark!

Measuring bull shark Caption: Citizen scientist helping the RJD Team work up a bull shark

Jake Jerome and Dr. Hammershlag pulled the 2.19m (7.2ft) female onto the boat. We did our usual workup on the shark before Neil implanted an acoustic tag under her skin. The tag will be used for the Urban Shark Project, a study on sharks in urbanized environments. After returning her to the water we continued to pull lines. We didn’t come across anything until line 15. We pulled up another female bull, this one larger than any bull shark I had seen before, 2.9m (9.5ft). After the workup she was fitted with a SPOT tag and released. As we pulled lines that day we could see people swimming and paddle boarders paddling. The fact that both the sharks and beach goers were coexisting in the same area really brought home he fact that humans aren’t on sharks’ menu.

Bull shark aerial view Caption: Jake and Dr. Hammerschlag reeling in a bull shark

Bull shark view Caption: Jake and Dr. Hammerschlag reeling in a bull shark

In two days we caught seven nurse and two bull sharks, quite the successful trip. Thank you to our citizen scientists for joining us on this trip. I’m sure they had as much fun as we did!

Shark tagging with citizen scientists

March 3, 2015/0 Comments/in Shark Research /by aanstett

by Hanover Matz, RJD Intern

On Saturday, February 21^st, the RJD team set out with a group of citizen scientists for a fantastic day of research. The morning was cool and windy, with some rough waves offshore. For everyone’s comfort, Captain Eric decided to stay closer to shore that day, taking us to the Safety Valve in Biscayne Bay for our day of tagging. The Safety Valve is a series of sand flats that many different species of sharks frequent. We set up our gear onboard the Diver’s Paradise boat. Each drum weight used to fish for sharks is attached to a buoy and approximately 70 feet of monofilament line. This fishing line is attached to a swivel on the top of the drum weight, allowing any hooked sharks to continuously swim and breathe. Most sharks are ram ventilators, and must continuously swim to pass water over their gills. In addition, circle hooks on the end of the line ensure that the shark is safely hooked in the jaw. Once the gear was onboard, we set out on the water.

The RJD interns explained the work up process to the citizen scientists on the way out to the site. Each guest had the chance to participate in actual scientific research, helping the interns collect date on each shark in the form of nictitating membrane tests, size measurements, and fin clip samples. We reached the site and began deploying our ten drum lines. Each drum line is allowed to soak in the water for 1 hour before it is collected. During this wait interval, the RJD interns and guests collected environmental data. Data on seawater temperature, salinity, and dissolved oxygen content provides information about the abiotic factors different shark species experience.

Figure 1: RJD interns help the citizen scientists deploy the lines.

After 1 hour we returned to collect our lines. On the first set, we pulled in a beautiful female lemon shark. Lemon sharks can be identified from other species by their second dorsal fin, which is almost as large as their first dorsal fin. They also have a brown-yellow color. While the shark was secured on the platform, a pump was placed in its mouth to pump water over its gills. This keeps the shark calm and allows it to breathe during the work up. The citizen scientists assisted the RJD interns with the work up process, helping to put a small tag at the base of the dorsal fin. The work up was quickly completed, and the shark was released back into the water. If the shark is ever caught again, the tag will help identify it to provide data about its movement patterns and life history.

Figure 2: A citizen scientist prepares to administer a nictitating membrane test on a lemon shark. The quick jet of water to the eye helps test the shark’s stress levels and reflex.

The weather remained clear as we continued setting out drum lines. Our next shark of the day was another lemon, but this time it was a male. Male sharks can be differentiated from females by the pair of clasper organs found at the base of their pelvic fins. Length measurements, a fin clip sample, and a blood sample were taken from the shark. These samples provide information about the shark’s health and diet. Blood samples can also be used to determine if the shark has recently been exposed to any diseases. Once the data was collected, the lemon shark was released off the platform.

Figure 3: Length measurements are taken from a blacktip shark.

Our last set of drumlines came up without any sharks, so we set five more lines for one last shot. After waiting an hour, we went back to pull up the lines. Our luck held out: on the last few lines, we caught a third lemon shark and a blacktip shark. Blacktip sharks get their name from the black tips on the edges of their pectoral, dorsal, and caudal fins. These sharks are very fast predators, able to dash off through the water with blinding speed. The sharks were safely secured on the platform at the stern of the boat. With the invaluable assistance of the citizen scientists, the RJD interns collected the necessary data and carefully placed the animals back into the ocean. As the last shark swam off, we were reminded of just how incredible of an opportunity it is to be able to work with such amazing animals. The boat headed back to shore, a successful day of shark tagging behind us.

Shark Tagging with MAST

December 15, 2014/0 Comments/in Shark Research /by aanstett

By Daniela Ferraro, RJD Intern

On Saturday, December 6^th, RJD embarked on a shark-tagging trip with a wonderful group of students from MAST Academy. Right before finals, this trip couldn’t have come any sooner. I woke up early to absolutely beautiful weather and knew the day was going to be a great one. I grabbed my gear and headed off on Dani’s taxi service, picking up several other interns on our way to Diver’s Paradise. We arrived around 8am and quickly went to work loading up all of our equipment and gear so we could get out on the water!

A participant conducts a reflex test of a shark’s nictitating membrane, or ‘eyelid,’ which is a measure of stress levels.

We headed out from Crandon Marina and headed towards Stiltsville Channel. With higher wind activity than normal, we decided not to add extensions onto our lines. After a safety talk with trip leader Austin and Captain Eric, we were on our way. As the rest of the interns got busy setting up our drumlines, Gabi and Beau gave a quick overview of all of the workup we give each shark: nictitating membrane test, measurement, fin clip, and tagging. With the help of the students from MAST, and our additional guests, we set out the first ten drumlines to soak for an hour.

Hannah and Gabi assist a participant in taking measurement data of a shark.

Our day began with a bang and we pulled up a 158 cm female blacktip on our very first line! The group did a great job helping us take measurements and tissue samples and placing a tag in the shark’s dorsal fins for future identification. For some of the group, this was their first time seeing a shark and the RJD team was just as excited to share this with them. With spirits high, we had a lot of help pulling in the lines on our first set. Most of our bait came back with a few bites out of them, if they came back at all! In the middle of our second set of lines, we managed to pull in a beautiful male lemon shark, measuring in at a total of 224 cm. Towards the end of the day, our group kept up their enthusiasm and it paid off: on our second to last line, we pulled in another female blacktip! Hannah and I held down the shark while our team did a quick workup and she was released in excellent condition.

Our whole group after a successful shark day!

The group was essential in helping us do our work ups on the sharks, and each shark team was prepped and enthusiastically ready to go just in case we caught a shark. With the help of Beau and new intern Emma, we also managed to take morphology measurements on all three sharks. Gabi and Austin also got blood from both blacktips and the lemon shark. This data will be used in several projects going on in the lab. Overall, we had a fantastic day on the water and the RJD team looks forward to going shark tagging with MAST Academy again!

Shark Tagging with Gulliver Prep

December 9, 2014/0 Comments/in Shark Research /by aanstett

By Alison Enchelmaier, RJD Intern

This trip couldn’t have come sooner. I’d been in my office for far too long and a tagging trip was long over due. Before the sun began to rise Sam and I piled into the car and headed to West Palm Beach. We met the rest of the team at Jim Abernathy’s Scuba Adventures at 7:30am and began loading up gear. With only 4 team members, I knew today would be a busy one. When our guests, Gulliver Preparatory’s Oceanography Club, arrived Dr. Neil gave everyone a briefing about shark conservation and the importance of our research before heading out.

As we left the harbor the waves began to grow higher and higher, until we were in 5ft high seas. It was difficult to safely move around the boat, much less tag, so the captain suggested we set lines closer to the harbor. To a resounding yes, we headed to the intercostal area, a location we had never tagged in before. The ocean flattened out to minimal waves as we reached our location and set our lines.

After we demonstrated how to set the lines, the Gulliver Prep students enthusiastically helped set the first 10 lines of the day. We headed back in to pick up a guest photographer and Dr. Neil demonstrated how to work up a shark and the research behind each sample. After letting the lines soak for an hour, we headed back out to pull in lines. As the first line was pulled in, no one expected anything to be on it since we rarely catch a shark on the first line. To our surprise the line was taut and a 216cm (~7ft) male nurse shark came to the surface! The deck was a flurry of activity as we brought the shark on to the boat, everyone excitedly chattering about such a lucky find. We worked up the shark in a few minutes and released it back into the water in good condition.

Nurse shark being worked up Caption: Gulliver Prep student helping the RJD team work up a nurse shark.

The first shark put us in high spirits, and we continued to pull in lines. On the 9^th line we caught another male nurse shark, this one smaller at 186cm (~6 ft). After working up the second shark we continued to pull up lines, but didn’t see anything until the 18^th line. As the line was pulled in, Jake said that something was on the line but it didn’t feel big enough to be a shark. As it reached the surface we got our answer: a gafftopsail catfish! The hook was quickly removed and the catfish was returned to the water, but not before getting slime on everything it touched!

An unexpected catch

In total we caught two male nurse sharks. We rarely find so many male nurse sharks in one trip! Hopefully the data we collected can help us figure out why they were there. Over all it was great day out on the water. I hope the Oceanography Club From Gulliver Prep had as much fun as we did!

Thanks for a great day on the water Gulliver Prep!

Shark Tagging with SLAM Academy

November 14, 2014/0 Comments/in Shark Research /by aanstett

By Hannah Calich, RJD Graduate Student

Last Friday was a great day of shark tagging. Not only did the RJD team get to spend the day with the fabulous students and teachers from SLAM academy, but the day was documented by a CBS film crew!

A great day with great people.

The RJD team met at Crandon Marina at 8 am to begin loading up “Divers Paradise”. It was beautiful out and we knew it was going to be a great day. Once SLAM and the CBS crew showed up, the RJD team introduced themselves and Dr. Neil gave everyone a briefing. Since it was such a gorgeous day and the water was quite calm we decided to head offshore to a deep reef.

Once we got to the site we quickly 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. When we got to line 3 we felt a familiar tug on the line and the team got ready for action. As we pulled in the line we determined we had caught a feisty female nurse shark that was approximately 250 cm long! Unfortunately, as we brought her in she managed to slip the hook and swim away. While it’s always a bit disappointing when a shark slips the hook it was great to see such a strong and healthy animal.

A kiss for good luck!

We continued checking and rebaiting the lines but the next 14 lines came up empty. However, something was eating our bait and we knew it was only a matter of time until we caught another shark. By line 18 the action picked up again when we caught another 251 cm long female nurse shark. The RJD team secured her while the students went to work collecting data. Within a few minutes her workup was complete and she was on her way again. Lines 20 and 22 also came with their own ~250 cm female nurse sharks! Each time a new shark was caught a different group of students came to the platform to help the RJD team collect data.

In the end it was a very interesting day because all 4 of the sharks we caught were ~250 cm long female nurse sharks. Hopefully the data we collected can help us determine what they were all doing there. Thanks again SLAM, it is always a pleasure to go out with you guys. I can’t wait until the next trip!

Shark Tagging with Big Brothers Big Sisters

November 14, 2014/0 Comments/in Shark Research /by aanstett

By Jessica Wingar, RJD Intern

When I woke up on Saturday morning, I was incredibly excited to be going shark tagging. I had been looking forward to this trip all week, and I saw that the weather was going to be perfect. It was going to be sunny and high 70s to 80s all day. I grabbed all of my gear and headed to Diver’s Paradise at Crandon Marina.

The RJ Dunlap team arrived at Diver’s Paradise around 8am to load the rest of the gear onto the boat. We were all ready for a great day of tagging with a great group. The group from Big Brothers Big Sisters arrived soon after and they were all very excited to be going shark tagging with us today. We added extension lines, since the weather was good enough to go to a deeper site. Captain Eric gave a safety briefing followed by Dani, who gave an explanation of our drumline system.

We were all filled with anticipation going out the site, which was just off of Miami Beach. The group came to the back of the boat to see how we deploy the lines. Then they helped us deploy the rest of the first set of ten lines. Everyone was very enthusiastic and so helpful. The first ten lines went out smoothly. We then let the lines soak for an hour.

Deploying the lines.

Our first shark was a large nurse shark. I think it may have been the biggest nurse shark I have ever seen. We quickly brought the large animal up onto the platform and did the work up. Everyone got a chance to touch the shark, which has very different skin than most sharks. Our next shark was a sandbar, which was extremely active on the platform. We did the workup in less than five minutes and the shark was put back into the ocean in excellent condition.

Getting data from a Sandbar shark

After these two sharks we got data on another two nurse sharks and another sandbar shark. All of the workups were done quickly, and everyone on the boat had an opportunity to help with at least one aspect of the work up. We had a great day, with a lot of important data collected. I hope that the group from Big Brothers Big Sisters had as amazing as a day as I did. I enjoy every trip that I go on and appreciate all the opportunities that I have to help aid in the conservation of these incredible animals.

Group picture, back on the dock!

Shark tagging with Our Lady of Lourdes Academy

November 10, 2014/0 Comments/in Shark Research /by aanstett

By Jessica Wingar, RJD Intern

Waking up on Sunday morning, I was extremely excited to be going shark tagging, since it was my first trip in a few months. I got up, checked the weather, it said less than 60 degrees. I was very surprised, doned my sweatpants and sweatshirt, and set off to Diver’s Paradise at Crandon Marina.

We arrived at Diver’s Paradise around 8am and loaded the gear onto the boat. Despite the fact that we were freezing, we were all anticipating a great day of shark tagging. The group from Our Lady of Lourdes Academy arrived around 9am. Captain Nick gave a quick safety briefing followed by an explanation of our drumline system by trip leaders Dani and Jake. We had added extension lines because we were going to go to a deeper site.

Dani cuts up bait on the way out to the site.

The girls and teachers were all very excited while we headed out to the site. Once we got the site, the captain made the decision that it was too choppy to shark tag there. Instead of the deep site, we went to Stiltsville instead. The team quickly took the extension lines off, and prepared the first several lines to go out.

After about another half an hour, we suddenly felt the boat start to slow and we saw the famous houses at Stiltsville. The team gathered the students near the back of the boat to demonstrate how we were going to deploy the lines. After the first line, the students were given the opportunity to deploy some lines. The students were organized into groups, which made the whole process run very smoothly.

Our first shark was a gorgeous blacktip. We swiftly brought the animal up onto the boat and did the work up. With the help of the students, the shark was back in the water within five minutes. Our next shark was a small nurse shark, which wriggled its way off of the line. We then worked up a blacknose followed by a beautiful 230cm lemon shark. This was only the second lemon shark I have ever seen. They have such distinctive teeth and I was in awe at the splendor of this animal.

A beautiful blacktip shark.

After the lemon shark we were able to work up another blacktip, blacknose, and a sizeable nurse. All of the sharks were worked up quickly with the help of the students and teachers. We had a great, busy day seeing a lot of variety of shark species. Every trip that I go on is different and every trip gives me the reminder that I am so lucky to have these opportunities. I hope that the students and teachers had as great of a day as I did and are now encouraged to go out and do more conservation work.

Group picture back on the dock.

Shark Tagging with 360 Destinations

November 7, 2014/0 Comments/in Shark Research /by aanstett

By Beau Marsh, RJD Inter

We enjoyed yet another beautiful day of shark tagging. The RJ Dunlap team had the pleasure of taking out the 360 Destinations group. Since the group was rather large, we had the added excitement of sending out two boats, in tandem. Spirits were high as everyone assembled at the Crandon Park as it was a gorgeous day. Plus, there was some playful jesting between the two crews over who would see more sharks. The competition would be fierce! Today’s destination for both boats was Soldier Key, a brisk 30 minute boat ride away. As we were preparing to depart the marina, we were met with a pleasant surprise. A friendly manatee graced us with its presence in order to get a drink of freshwater from the dock hose. Our sirenian friend was a great preface to a fun day, and saw us off to Soldier Key.

In route to Soldier Key our enthusiastic guests were given a rundown on the kind of research our program conducts. They were excited to know that they would be assisting in collecting real data that actively works toward the education and conservation of shark species. Everyone was engaging and friendly and showed a true interest in the work our team does. It was a treat getting to know some of our guests. I even met a fellow Chicago native (Go Blackhawks!). Upon our arrival at our fishing spot, both boats spread out and deployed our respective drum lines. Of course, the helpful guests of 360 Destinations assisted us in deploying our lines. I was impressed with their willingness to assent to our very serious superstition of kissing the bait before deployment. Anyways, they were intrigued to interact with our specialty gear and learn how our drum line system allows us to safely catch and release sharks with the animal’s health in mind. Once our 10 lines were in the water, we allowed them to soak for an hour. This gave us the opportunity to demonstrate the process involved with working up a shark once we catch one. We displayed all of the tools we would be using and explained what kind of samples are collected (e.g. nictitating membrane, measurements, fin clip, blood). We also showed them how we insert our tags into the dorsal fin. It was great to see the whole group getting involved by asking questions and getting a good look at all of our gear. Our trainees were well prepared.

Once the obligatory soak time was up, we headed towards our first line. We demonstrated the proper form in pulling up lines, and then let our excited guests take have a try. Unfortunately, our first set of lines did not hook anything. Although, we were still having a great time on the water in beautiful weather. We had been in communication with our other boat that was out, and they informed us that on their first set they were lucky enough to catch a nurse shark. The pressure was really on now! So, we put new baits on our lines in hopes of better luck on the next set.

We returned to our lines for our second (and final) set of lines. We had 10 more chances left. It was a slow start. Our first five, again, rendered nothing. We pulled up these lines and stowed them away for the day. Finally, the moment everyone was waiting for came on our sixth line. Like the other boat, we caught an amazing nurse shark. Its total length was about 2.3 meters, and she was feisty until we carefully restrained her. Everyone from 360 Destinations was standing by and ready with their instruments. They did a fantastic job, and helped us to collect each sample without error. It was a successful workup, we safely released the nurse shark in a timely fashion. It was a great experience for everyone involved, crew and guests. We retrieved the rest of our lines and returned to the marina.

Over the course of the afternoon, each of our boats caught a nurse shark. That is two new sets of data RJ Dunlap can use in our research. Also, it is two rare opportunities for people to safely interact with two amazing animals. We should all feel fortunate that to have had such an experience. Thanks to all the 360 Destinations guests. RJD had a great day on the water with everyone, and we hope you a memorable time.