Shark Tagging with the Children’s Wish Foundation

By Tim Hogan, SRC Intern

On the morning of Friday, April 8th, a crew of 10 SRC interns and their captain gathered together to prepare for a day of serendipity and many sharks. Our guests, associated with the Children’s Wish Foundation of Canada, came along to meet our team leader, David Shiffman, and get some hands-on experience with the boat and sharks. The volunteer’s enthusiasm and eagerness to learn made them fit right in with the rest of the crew. After preparations were made, the Diver’s Paradise made its way to the Sandbar Palace, a deep reef with high productivity. It had previously been the site of very successful, high-catch trips, and hoped the same would occur on this day.

The second line we pulled up had tension, meaning that something was on the line. As it neared the boat, he was identified as a nurse shark, one of the more commonly caught species. This one, however, was extremely energetic and acrobatic, and began taking various evasive maneuvers, primarily consisting of twirls, flips, and twists. Eventually, he fulfilled his dream of becoming an escape artist, detaching from our line with no damage done to itself. Even though we couldn’t get any data from it, the early shark enhanced our optimism, the anticipation built with each retrieved line.

Our patience was quickly rewarded 5 lines later, as an even larger nurse was brought in with the buoy. This time, we managed to bring it onto the platform, and got the chance to collect our measurements and a blood sample. Our volunteers were eager to get involved and helped with the workup. During the downtime between lines, the volunteers took the opportunity to observe the blood analysis procedure, and also measured water samples.

 Shark Intern Leila AtallahBenson showing volunteers our blood analysis protocol

Shark Intern Leila AtallahBenson showing volunteers our blood analysis protocol

As the day progressed, we only seemed to get luckier with each drumline we pulled. On the second line on the third set, we could see the distinct dorsal fin of a great hammerhead approach the boat from the surface. The titan measured up to 328 cm (about 10’9” in the imperial system, which is basically twice my height), and it was released in good condition after our protocol. Less than five lines later, as if we received the blessings from the ocean itself, we brought in a scalloped hammerhead. Distinguished by a more curved head, it is one of the rarest sharks found on trips, and is caught three to five times a year. We went through our protocol quickly and cautiously to ensure it returned to the ocean in the best possible condition.

While we were perfectly content with our first two sets, our final ten lines had us end with a bang. Starting strong, we brought in the namesake of our site, the sandbar shark. The personal favorite of David, he was ecstatic beyond description as we went through our protocol. It was easy to see why, with its faint, iridescent skin and gorgeous color. Two lines later, we managed to pull in the most common shark in South Florida, the Atlantic sharpnose shark. Sharpnoses are typically much smaller out of most of the other species we catch. This one was in particular had a length of 116.5 centimeters, which is almost a meter shorter than the next smallest one.

The sharpnose is the most common shark in South Florida, and is also one of the smallest. The pump flows oxygenated water over its gills, ensuring that it can breathe while we do our workup

The sharpnose is the most common shark in South Florida, and is also one of the smallest. The pump flows oxygenated water over its gills, ensuring that it can breathe while we do our workup

The remaining time was more calm, though we did manage to bring in another nurse shark. At the end of the day, it was difficult to not appreciate the sheer diversity of sharks. Of the nine sharks we brought in, there were four nurses, two great hammerheads, one sandbar, one sharpnose, and one scalloped hammerhead. Our volunteers were able to see sharks in their many shapes, sizes, and functions. We returned to shore knowing the day was extremely successful, and more than grateful that we got as lucky as we did.

Our volunteers gathered around one of our Nurse Sharks after taking data and measurements, with interns Jake Jerome, team leader David Schiffman, and intern Emily Nelson

Our volunteers gathered around one of our Nurse Sharks after taking data and measurements, with interns Jake Jerome, team leader David Shiffman, and intern Emily Nelson

Shark Tagging with South Broward 9/26/2014

By Jake Jerome, RJD Graduate Student and Intern

Last Friday marked the first time that RJD went shark tagging out of West Palm Beach, and it proved to be an exciting first! We were joined with one of our more frequent school groups, the South Broward Reef Dogs. After making the trek up to West Palm, we loaded up the Deep Obsession with our gear and set out with the crew from Jim Abernathy’s Scuba Adventures aboard.

With choppy seas and rain falling down on us, we launched our first 10 drumlines in the hopes of catching our first shark in West Palm Beach. Despite the weather conditions, everyone on the boat kept spirits high and we all had a good feeling about the day. After letting the lines soak and collecting some environmental conditions with the help of our guests, we began pulling up our lines.

After a slow start and the rain still pelting down on us, we managed to pull up an Atlantic Sharpnose, the most abundant shark species in South Florida. Once we brought the shark aboard, we began our quick workup to collect data for our over 9 research projects. In less than 4 minutes we were able to collect multiple morphological measurements, a fin clip, draw blood, place an identification tag and perform nictitating membrane stress tests. Once these procedures were completed, we released the shark and returned to pulling in our lines.

Trip1

A participant helps take a fin clip, a small cartilage sample that will help reveal long-term toxicology and dietary patterns.

After our first shark we seemed to hit a slump going into our second set of drumlines. After switching the crew around, our luck took a drastic turn for the better! While pulling up one of our final drums of the second set, we knew immediately we had something big on the line!

After hearing our captain shout “Shark,” all eyes turned desperately towards the water looking for the animal. Once the shark hit the surface we could see that it was a hammerhead! After we had the large male secured next to the boat, we realized that we had a Scalloped Hammerhead, a species that we rarely get to collect data from. Knowing this, we quickly collected as much data on the animal as possible and then attached a satellite tag so we could follow the shark’s movements after we released him. For the rest of trip, spirits remained high and we were fortunate enough to catch two more sharks, a feisty blacktip and a large bull on our very last line of the day.

Trip2

Measurements of the scalloped hammerhead are quickly taken while a satellite tag is being attached.

All in all, our first trip out of West Palm Beach proved to be a successful and exciting one. We were able to collect data from four sharks of four different species and were able to satellite tag a Scalloped Hammerhead! Thank you so much to the always awesome South Broward Reef Dogs and the rest of the crew from the day.

Trip3

Our awesome group for the day, the South Broward Reef Dogs!

Breaking in the new boat!

2/3/12

Last weekend, students from the Archimedean Academy joined the RJ Dunlap team for the first of many voyages on Captain Curt’s new boat! This new vessel, named after Captain Curt’s soon-to-be-born daughter, is a welcome addition to RJD. It’s size, range, and cabin space will allow our team to do even more research in the Bahamas and other far-away sites.

Students from the Archimedean Academy pose on Captain Curt’s new boat!

 

We went to Middle Grounds, a site in the Everglades National Park known for having lots of sharks. Nutrient-rich runoff from the Everglades creates a rich feeding ground for many species of sharks. Some of our highest catch-per-unit-effort (a measure of shark abundance) has been at this site. Our catch didn’t disappoint- in total, we caught, tagged, and released two blacktip sharks, an Atlantic Sharpnose shark, and a blacknose shark.

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