Expedition leaders: Annie Guttridge and Vital Heim

Crew: Rantaa, Rosie, Hannah, Kaylee, Bree, Brian, Daniel, and Xavier

Introduction

Brimming with unforgettable memories, an incredibly rare hammerhead encounter, and a wealth of shared knowledge, our team left Andros inspired and excited for the next adventure together

This blog was kindly written by research assistant Hannah Richey.

Day 1

Anticipation was building at the Tropic Ocean Airways Airport as the crew began to arrive and gather in preparation for the flight from Ft. Lauderdale to the beautiful island of Andros, Bahamas. As we waited for some weather to pass to ensure a safe flight, Annie gave a safety briefing to the crew and spoke on what exciting experiences awaited us in Andros. Once we got confirmation, it was time for us to board the plane and enjoy the amazing views of the Atlantic.

The deep blues of Florida's pelagic quickly bloomed into crystal clear turquoise waters. Everyone was gazing out of the windows, searching for any familiar shadows of rays and sharks cruising through the waters. As we passed over land masses, Annie pointed out the various islands, such as Bimini. In the distance, a large landmass began to emerge. Andros crept slowly into view as we approached our destination. From the air, habitats such as mangroves, reef patches, and blue holes could be seen. The plane landed softly on the runway and came to a gentle halt. After deboarding and making it through customs, several taxis drove the crew to the Andros Island Bonefish Club, our home for the week.

Once we arrived, the plan was to settle into our assigned rooms and gear up to head out on the water! Beforehand, Vital spoke to the crew collectively about several key topics including, safety on the boat and when working up sharks, the specificities of tagging equipment and gear, and of course the safety and well-being of the animals we’d encounter. Once the briefing was complete, we began loading the equipment onto the boat and greeted our captain, Marvin, who was very welcoming to everyone and just as excited as we all were. We made our way to the first location, setting up the equipment ahead of time. This involved learning how to tie bowline knots to ensure the proper attachment of ropes and lines to the buoys and weights. The boat slowed to a stop and it was time to put the gear in the water. As the line was tossed in, the buoy followed, and the large weight that kept the equipment in place was gently lowered to the sand. After all five buoys were in the water, the anticipation set in, as we all kept a sharp eye out for any signs of movement. The buoy becoming vertical and having visible tugging is an indicator that a shark is on. However, if it's a large shark, the buoy could be tugged completely under or even dragged across the water! The moments of waiting are suspenseful, but always rewarding.

One of the buoys began to shift, slowly tilting and bobbing until it jolted and stood vertical on the water's surface. We rode over to it, everyone at their stations and in position. The GPS coordinates and buoy numbers were recorded as well as the time. With the tags already prepped for use and logged on the data sheet, all we needed to do was carefully bring the shark to the boat for a successful work up. As we approached, a boat hook was lowered into the water, hooking the rope so we could begin pulling the gear out of the water. The weight is pulled in and set aside, as well as the buoy. As more of the rope was being pulled into the boat, all eyes were on the water, searching for what awaited us. Once we reached the monofilament, only a few feet was left between us and our first shark of the trip. A large brown shadow began to emerge from the sandy flats until it broke the surface, revealing itself to be a nurse shark! For this particular species, the tail rope is gently secured over the second dorsal fin and anal fin, ensuring the safety of the nurse shark's caudal fin area. Other species will have the rope secured over the caudal fin before the tail forks. In this case, Kaylee was shown how to place the tail rope by Vital, while Daniel held the dorsal fin, and Rantaa steadied the head and monofilament. All of these factors are key to a quick and successful tag and release. Holding the dorsal fin entails a two handed steadfast grip, ensuring the shark is stable for an efficient tagging process. A PIT tag reader is then used to scan under the dorsal on both sides of the animal for a possible recapture. If no number appears, it’s a new shark. For nurse sharks, only a PIT tag is used, this is due to their typical behaviors of laying under rock formations, which would likely knock off an external tag. PIT tags, slightly larger than a grain of rice, are inserted via syringe in the area below the dorsal fin. Once the tag is in, the pit tag reader is used again to ensure a successful placement. Measurements of the shark are then taken. Typical measurements include a pre caudal length (PCL, tip of the nose to beginning of the tail), a fork length (FL, tip of the snout to the fork in the tail where the upper and lower lobes of the caudal fin come together), and a stretch total length (STL, tip of the nose to tip of the tail), however for nurse sharks, only the PCL and STL are taken since they don’t have a defined split where the tail forks. After measurements were completed, the shark was safely released and swam off strong.

The team was delighted to have completed our first work up of the trip and were looking forward to other species we may encounter. It was getting late in the evening and time for us to haul the gear and head back to the lodge. There we had a delicious dinner prepared by the wonderful Bahamian staff. After a quick briefing about the plans for tomorrow, we headed back to our rooms with high hopes and excitement for what awaited us the following day.

Day 2

The morning of the second day was upon us and everyone met for a quick breakfast and packed lunches for the boat. Afterwards, we loaded the boat for another day full of shark research. We made our way to a back reef area, preparing the tagging equipment, data sheets, and gear along the way. Once we arrived at our desired location, it was time to get the gear in the water and begin patiently watching for any activity. Not long after the first set of drumlines were deployed, we had our first shark on! The first shark of the day was a large nurse, who was secured using the same tail rope, dorsal fin, and head stability methods as before (this goes for all sharks.) Once the shark was secure, the PIT tag reader was used to confirm that we had a new shark. A PIT tag was then placed below the dorsal and read again using the reader. Measurements were quickly taken afterwards and the shark had a safe and swift release. Once the buoy was redeployed, another set began to sway and tipped vertically on the water. Another shark was already on! After hauling the gear, and bringing the shark to the boat, it was identified as a nurse, tagged, and quickly released. We went on to successfully tag and release many more nurse sharks one after the other.

Anticipation was building for a new species to make an appearance, then suddenly another buoy went off, but in a different manner. At this moment everyone had high hopes that something different awaited us beneath the waves. The gear was hauled into the boat and as the shadowy outline came to the surface, a slender shark with a small dorsal fin and yellow-gray hue emerged. One distinguishing feature, a black dusky blotch on the tip of its snout, identified this species as a blacknose shark! Hannah and Kaylee were collecting data on the location of the buoy while Brian assisted with bringing the gear in, Daniel secured the tail rope, Rosie held the dorsal fin, and Bree stabilized the head by holding the monofilament. Vital swiftly inserted a PIT tag and an external DART (Casey) tag. The DART tag is a slender yellow external tag that is placed under the dorsal fin on all sharks aside from nurses. Once the tagging process was complete, PCL, FL, and STL measurements were taken and documented. In the meantime, Annie was documenting the workup with photos and videos, encouraging all of us every step of the way. Being able to show the public the importance of research and the care in which the sharks are handled is highly important, and she strives to show the significance and beauty of these animals through her photography and conservation efforts. When the data sheet was complete, in one quick motion, Daniel released the tail rope, the monofilament line was removed, and Rosie assisted the shark's release by gliding the shark off by the dorsal fin. We watched as it swam off strongly and were ecstatic about working with a new species. Shortly after, another blacknose shark made an appearance and was successfully tagged and safely released.

With all five drumlines redeployed and the team diligently on stand by for another shark, the action had gone quiet. A small weather system was blowing in and the clouds grew darker around us. We had hopes for one more round before having to haul the gear. Our patience rewarded us, and a buoy was hit with a large splash. We approached, pulled the gear, and were met face to face with a large Caribbean reef shark!

Once it was close to the boat, Vital assisted Kaylee with securing the tail rope, Hannah held the dorsal fin, and Rantaa stabilized the head by holding the monofilament. For reef sharks, 3 tags are utilized. Both the PIT tag and the DART (Casey) tag are placed below the dorsal fin, and then an internal acoustic tag is carefully inserted. To do this, the shark is turned upside down, which places it into tonic immobility. During this state, we are able to safely insert an internal tag and can also check the sex of the shark. The acoustic tag is placed into the body cavity of the shark. Each time it passes within 1500 ft (500 m) of a receiver it will send an ID code, time, and date stamp. They have a battery life of about 10 years and provide important data that is monitored, such as movement and habitat use. Vital performed this procedure and sutured the tag area closed. Sharks have an incredible healing capability, so this procedure is safe in the hands of the professionals and the tag provides essential data for a much longer period of time. This data in-turn can help us find out where these sharks are going during certain times of the year. Hereby protecting them due to collaborations with fisheries management (outside of The Bahamas as the Bahamas is a shark sanctuary) to close off fishing in particular places these sharks may pass through. This same practice is used with hammerheads that are equipped with SPOT or satellite tags. Once the 3 tags are placed and the data has been recorded, it’s time for a careful release. We admired the shark as it swam off and noted that it had an excellent departure.

We were lucky enough to successfully tag another caribbean reef with the same methods and had another swift release. The last shark of the day was another large nurse shark, that was tagged and carefully released. At this point, the weather had moved closer to us and it was time to haul the gear. The storm grew rapidly and we made the trek back to the lodge, braving the rain and swells. Marvin, our boat captain, maneuvered us through the storm and safely back to the lodge. Once we were there, everyone cleaned up and had another wonderful dinner. Afterwards, we did some fun team bonding games and finished the night off by learning how to make new hooks. Overall, we ended the day with 10 sharks!

Day 3

The weather was not kind to us on the morning of day three. We awoke bright and early at 6:00 AM in hopes to head to a prime spot for silky sharks called the Tongue of the Ocean (TOTO). This is a region of deeper water in the Bahamas separating the islands of Andros and New Providence. Its tongue-like shape from an aerial view is how this pelagic region obtained its name. A large storm system surrounded Andros, and didn’t have plans of dissipating anytime soon. While the team couldn’t head out on the water, we were able to gain valuable knowledge by attending a lecture session on the sharks of the Bahamas given by Vital. During this time we were able to dive deeper into the local species of Andros while we waited for a window of opportunity to head to the pelagic zone. After some time, the rain had slowed down and we went for it! Once we made it to our destination, we prepared our polly-ball and deployed the set. We waited patiently, no sign of movement or stirring in the water, but still hopeful. Our goal was to maximize our time there due to the weather conditions in the morning and high winds predicted for the rest of the week.

Unfortunately, no silky sharks were seen, but the crew did get the opportunity to go for a snorkel by the navy buoy. Once everyone was geared up and in the water, it remained quiet, but utterly serene. Nothing but endless shades of blues and sun rays that had peeked through the clouds and graced the water below us. We held onto a line attached to the boat and soaked in the moment! As we patiently waited and observed the fish surrounding the buoy beautiful mahi mahi decided to briefly join us! Rainbow runners also made an appearance, swimming in sync with one another as they passed under us. A group of juvenile pinfish also swam between our fins, using them as makeshift hides while the larger fish swam about. A few jacks also joined us, and were not shy to get close. We concluded the dive and piled back onto the boat, ready to make the journey back to the lodge. Although we didn’t encounter any silky sharks, the creatures and views we did see were magnificent. After returning to the lodge, it was time to get cleaned up for dinner and prepare ourselves for another day out on the water.

Day 4

The team gathered for breakfast early in the morning and had a short briefing on the plans for the day. Our first stop was a beautiful diving spot in one of Andros’s blue holes. These are vertical underwater caverns teaming with a variety of corals and marine life. Annie, being an experienced freediver, demonstrated proper diving techniques and encouraged each of us to take a dive and explore the cavern. One of the team members, Rosie, achieved a long term goal of completing a deeper dive into the cavern. With Annie by her side, and Rantaa kindly following with a Go Pro, she swam 9 meters (~ 30 feet) down into the darker portion of the hole and gilded carefully to the surface. Once she came up, we all cheered and celebrated. It was a great start to the morning, with much to look forward to

After our quick dive, it was time to set up the drumlines and get to work! We traveled to a back reef area and prepared the gear for deployment. Once we reached our destination and the buoys were in the water, anticipation set in for our first bite of the day. The first buoy went off and we headed towards it. Our first shark of the day was a Caribbean reef, which was tagged, measured, and safely released. During the work up, another buoy had been hit! This time it was a nurse shark. We inserted a PIT tag, measured her, and she swam off strong. The two buoys were reset and redeployed. Not long after, we tagged and released another Caribbean reef shark, followed by a nurse shark, and lastly a blacknose! At this point it was late in the evening and time to haul the gear and head back to the lodge to have dinner. We started the day off enjoying the beauty of Andros’s reefs, and ended it with a variety of sharks and an exceptional day of research.

Day 5

There is nothing better than waking up to the sound of waves brushing against the sand and the suspense of what the day had planned for us. The team was up early enjoying breakfast together and chatting about what sharks we hoped to see today. We planned to head to an area nicknamed shark hole; a deep blue hole known for the elusive sharks that call it home. At this area, we set longer drumlines, in hopes to find the sharks below. When the buoys were set, we lingered over the center so Annie could use a device called a hummingbird. This piece of equipment is a fish finder that uses sonar to detect marine life and underwater objects. It transmits sound waves from a transducer in the water that measures the amount of time it takes for the waves to bounce back after hitting objects. This information is then sent to the main device and processes the data as maps and charts on the screen. It can be essential for seeing what lies below. The morning was slow and quiet, no sharks in sight. We continued to check the buoys every 45 minutes, as per routine, but no luck yet. Eventually, one buoy was hit and we successfully tagged and released one nurse shark.

Since shark hole was at a standstill and slack tide was upon us, we headed over to our next destination. A beautiful habitat known for seeing lemon sharks called Isla’s Spot, named after Annie and Tristan’s daughter. We slipped into our wetsuits and made a short trek in the sand and into the water about knee deep. Here, Rantaa scraped a bonita fish into the water in hopes to bring in some lemon sharks. A blacknose shark joined first, followed by several lemon sharks. Seeing them up close was an amazing experience. They swam in front of us, brief glimpses of their noses breaking the surface as they snagged a piece of fish. Their yellow coloration gleamed under the water, almost blending with the sand. It was a wonderful experience to be so close to them. Mangroves are key habitats for lemon sharks, especially juveniles. They use the deep root systems to protect themselves from larger predators, all while learning to hunt efficiently. Once they’re large enough, they move to the open ocean. Seeing these lemon sharks in this space showed just how important it is to protect these habitats and ensure the sharks will be there for years to come.

The day was not done yet, in fact, it was just getting started. We left for a new location and were ready to get back to work! Once we arrived and the buoys were in the water, it was time to watch and wait. The waves were slightly rocky, and all eyes were on the buoys to ensure we saw if one went off. It was slow at first, until we got our first bite, or so we thought. When we pulled the line it was clean, no bait in sight. Another buoy went off, and again, a clean line. After some time, we got another hit, and this time we finally got our shark. Once we pulled in the gear, a nurse shark rose to the surface. The shark was secured, tagged, measured, and quickly released. The water was so clear we could watch him swim off and down to the sandy flats. Some time had passed after several bait checks and a buoy went off. We tagged and released a few more nurse sharks and redeployed the gear. At this time, the action under the water went silent, as if the world stood still beneath us. The waves continued to rise and fall, but there was something curious going on. A measure of time had passed, several checks were performed and every bait was still untouched. Maybe the sharks moved on, or maybe there was a reason nothing was around. Perhaps there was something larger roving beneath the waves. All eyes were on the buoys, the waves concealing them as the tide rose and fell. A swell came and all 5 buoys rose and hid behind the waves, when it fell, only 4 buoys were in sight. Every person on the boat was searching for a glimpse of orange! We quickly rode over to the exact coordinates in which the buoy was deployed. At this point, everyone was under the impression that something massive was on the buoy we were all searching for as the boat circled the perimeter. A couple minutes had passed from the time the buoy was missing until now, then suddenly we heard several people yell “There it is!” Sure enough moving at a steady pace, the rig was seen. The cloud coverage made it impossible to see any movements or shadows of what it could be. We extended the boat hook and managed to hook onto the rope. Vital and Rantaa began pulling up the rig. At the end of the rope, only several feet of monofilament separated us and the unknown shark. Whatever it was, it was large and powerful. All of a sudden, the monofilament went under the boat, the shark had switched sides. The line led down to a shadow of patch reefs below, and the clouds made the crystal waters too dark to see. The mono continued to be pulled into the boat so we could identify just what was below us. Only a couple feet was left, and the mono began to move out of the reef area and into the open. A MASSIVE shadow emerged from the reef, its hammer shaped head immediately identifying it. Hannah shouted “It’s a hammerhead!” and the atmosphere of the boat changed. The hammer satellite tag was retrieved from the head of the boat, Annie was preparing her camera rig, Rosie, Bree, and Kaylee were readying tagging equipment, Daniel was assisting Rantaa with the rest of the monofilament, Vital prepared the tail rope, and Hannah was on the data sheets. The whole team was locked in. As she rose to the boat, everyone was in utter shock and awe. Her sheer size, strength, and power were indescribable. From tip to tail, she stretched across almost the entire boat. Once she was close to us, it was then that we saw that she was foul hooked, meaning that the line was not stable and it was not safe enough for a workup to be done, for the crew and especially the shark. The process of working up a hammerhead must be precise and efficient for the health and safety of the animal. During the entire time a hammerhead is being worked up, there is a timer running. It is highly important that we make sure that there is a cut off time, even if the work up is not complete, to ensure the health and safety of the animal comes first. In this case, we released her without a workup. Once she was safely released, and the team was relieved to see her swim off strongly, the whole boat was full of emotions. Excitement, tears, and pure joy all around. After extensively reviewing footage and comparing opinions her total length was estimated to be between 4.5 - 5 meters or 14.7 - 16.4 feet. A world record sighting of a great hammerhead. Due to her size, she was also estimated to be over 50 years old. It was truly an extraordinary experience that none of us will ever forget. For some, it was a childhood dream to see a hammerhead of that size, and for others it was a moment etched in their memories that would inspire them further in their careers.

The day didn’t end there and the excitement didn’t fade away. We redeployed and went back to work! After some time, we had a nurse shark on the line. We brought the shark to the boat and swiftly tagged and released him. Another buoy was hit, but not by a shark! After pulling in the line, a giant remora revealed itself at the surface. We gently brought him on the gunnel of the boat so we could completely remove the line and place him back into the water. The sun was setting, we hauled the gear and traveled back to the lodge. The talk of the dinner table of course being the hammerhead we had seen. We tucked in for the night and looked forward to tomorrow.

Day 6

After an exciting day yesterday, the crew was wide awake and ready to go! After a quick breakfast, we began our day with a beach cleanup. From ropes, nets, fishing line, plastic, styrofoam, tires, and even a chair, we left the beach better than we found it and ensured the animals would have a safer and healthier habitat. We filled the truck bed to the brim with garbage and disposed of it at a local dump site. It’s always important to do your part in making the oceans a healthier place by cleaning up, starting with the smallest microplastic to the largest nets.

After our beach cleanup, it was time to fish! With the gear prepped and the first set of tags ready, the buoys were deployed in no time. Our first shark of the day was a nurse shark. The PIT tag reader was used to confirm a new shark and then a new tag was inserted. Measurements were quickly taken and recorded, and then the shark was carefully released. The buoy was redeployed back to its position and we waited for more action. The buoys were quiet, but with fresh barracuda on the line, we had hopes of seeing another hammerhead! Some time passed and we saw a shadow swim by the boat. Rantaa shouted that it was a hammerhead! The team watched on as the shark casually swam past our boat… and lines! Although she didn’t go for a buoy, we had at least confirmed another sighting for our database. We went on to tag and quickly release 3 more nurse sharks before hauling the gear before the sunset.

We traveled back to the lodge for a lovely dinner, entered data on the computer, and spent some extra time chatting with one another since it was our last full night. We dispersed to our rooms and headed to sleep for the night.

Day 7

On the morning of day 7, the team split into two groups. Vital, Rantaa, Kaylee, Bree, Brian, Xavier, and Daniel all went out on the water to continue tagging, while Annie and Hannah were joined by Saving the Blue field technician, Skye Minnis. Their objective was to visit the local elementary school and provide an educational presentation on the importance of marine life, specifically sawfish.

Team A, the fishing team, went out early and tagged 1 nurse shark and deployed an important new receiver. Receivers are essential in order to receive data from tagged sharks. It listens for pings from tagged sharks that swim by. When the tag is detected, the receiver records the tag ID number, along with the time and date. The team ended the day with just the nurse shark tagged, and headed back to the lodge to pack, shower, and head off to meet team B at the airport.

Team B, did a mini beach clean while we waited for the school to open. While walking on the beach, Annie found a perfect spot to draw a memorial for two close friends of Saving the Blue that have passed on, Bonnie and David. Each time she visits Andros, Annie does this to honor them and they are held closely in our hearts and thoughts. Once we left the beach, we made our way to the school. Annie and Skye presented about sawfish, the role they play in the ocean, the importance of conservation. We also gifted the children Saving the Blue t-shirts with depictions of a hammerhead, silky shark, and sawfish on the back. Annie gave each one a children's book that she published all about the regions of the Bahamas and the animals within them, as well as sawfish coloring pages. The kids were absolutely brilliant, there was joy and smiles all around. The trip to the school was a wonderful experience and showed the importance of shark education for the future generations. Before heading to the airport, we stopped and chatted with local fishers, asking about sawfish sightings and locations. Sawfish are globally critically endangered, and face issues such as habitat destruction and being killed for the use of their rostrum as a prize or souvenir. This information is key to helping us understand where we might be able to find them in hopes to tag them in the future to aid in conservation.

Everyone gathered at the airport and made it through bag checks and customs before boarding. On the plane, we spoke about our time in Andros and the memories we made. We watched out of the windows as Andros and the rest of the Bahamian islands faded from view, scanning for sharks and other moving outlines below. We safely landed in Fort Lauderdale full of new memories, a once in a lifetime hammerhead encounter, an abundance of knowledge, and close friends. For some, it was a step into their career, and others an expansion. For others, like Brian, it was the ability to watch his daughter Bree in action on the water, doing what she loves. In one way or another, this expedition motivated and excited each of us, and we all looked forward to the next trip back to Andros

Thank you

Thank you to our research trip leaders Annie Guttridge, Vital Heim, and Sorantaa Bain for guiding the team through an incredibly successful week. A huge thank you to our research assistants for their passion, determination and endless enthusiasm to work hard, learn and produce results. We would also like to thank the Andros Island Bonefish Club for their hospitality, and the hardworking and ever professional Marvin for his top class boating and captaining skills.

Gratitude must also go to Annie for her generosity in allowing us to use her images in this blog.