Tiger Beach Research Trip
June 8 - 11, 2008
Lemons everywhere at Tiger Beach
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June 8, 2008
Adult lemons greet us at Tiger Beach
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Today Doc, Steve and I stepped aboard the motor vessel Dollie just before daybreak. Capt. Pete fired up the engines, we untied the lines and were underway. We headed north almost 100 miles to a spot near Memory Rock up on the Great Bahama Banks. The location we stopped was a vast sandy plain with a shallow depth of between 15-20 feet.The name of this remote corner of the Bahamas is known as Tiger Beach, and dive operators have started taking divers out to this sand flat. The attraction is very simple - sharks - big sharks and in large numbers. We are here to deploy two transmitters on adult sharks, install two bottom monitor recievers to listen fo the acoustic tags, take DNA samples, and to help representatives from Lindgren-Pitman, Inc. to put some "shark-proof" mesh to the test.
Sampling lemon shark DNA with a pole-spear
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We anchored up and started to put chum in the water to attract the sharks. It didn't take long to get a good slick of menhaden oil and blood fanning out from the stern in the current. I went inside the boat to prepare my camera gear and wait for sharks to find their way to us. Steve had hung a huge snapper carcass off the back of the boat, so I was confident we would have some hungry customers showing up real soon. Within an hour we had six lemons circling the back of the boat. We started throwing bait in to them and drew them close to the boat with pieces of bait on lines. When they got within range we popped them with a pole spear to take a small skin sample for DNA analysis. More lemons joined the fray until we had approximately a dozen prowling off our stern. As we glanced around Steve and I saw a large dark shadow making a large arc about 100 meters behind the boat. We looked at each other and excitedly shouted "TIGER!!!". The large shark was wary at first but soon was making its way into the pack of lemons.
A lemon about to give our "chew toy" a proper test
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At this point we got some of the "sharkproof" mesh from LP, folded it and tied it together after stuffing it with some bait. We dubbed the test rig the "chew toy" and threw it out on a rope amid a few pieces of bait to the waiting sharks. The lemons made some impressive runs at the chew toy, grabbing, biting, shaking, and twisting it with their entire bodies. The tiger finally got up its courage and made a few sweeps in. It grabbed the chew toy and gave it a quick nip. Despite all the abuse the sharks dished out the mesh proved to live up to the challenge. It soon turned its attention to the large snapper carcass. It made three different passes at the large bait, but came in meaning business on the last run, grabbing the huge snapper head in its mouth and snapping the rope that held it after an energetic show of twisting and splashing. We pulled all the equipment in for the night and Steve and I slipped on our fins and eased into the water. The two of us bobbed on the surface and freedove with the large lemons and watched the tiger shark make two short passes to satisfy its curiosity. It was an amazing day - Tiger Beach definitely lived up to the hype. We went to bed tired but very excited to get to work the next day...
June 9, 2008
Securing a VR2 Receiver Unit to a sand screw
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We were up early on the second day and walked out onto the back deck to a beautiful site. There were more than ten adult lemons milling around the swim platform. The first order of business was for Steve and I to don our scuba tanks and secure the bottom monitors in place on the bottom. We took the reciever units, sand screws, and some miscellaneous tools and splashed off the boat. It was only fifteen feet to the bottom, but we had a lot of grunt work to do. I tested the substrate with a poker and found it to be all sand. That made our job easy. We took the large sand screws and I twisted it slowly deeper and deeper until only the eye bolt at the top was showing. At least three feet was below the bottom and should hold the unit in place through the worst storms. Two sand screws were in and we brought the hydrophone receiver units down and bolted them in place on their mounting plates.
Lemons inspect the VR2 monitor
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There were several lemons swimming around us as we worked and as soon as we backed off they cruised in to inspect their new high tech accutrements. Back on the boat we prpepared some of the LP fish boxes by stuffing them with bait. The boxes had large windows with their test mesh. A little weight to sink the rigs and we tossed them over board. We were lucky as the tides had swung us near the receiver units again so we went in for a quick dive and I took a bunch of pictures. After a little while we pulled the boxes and our anchor and headed out to do a little fishing. We caught a good sized grouper (which provided a delicious dinner later that night) but not much else.
Tiger Beach action by the Sonotronics receiver
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We re-anchored and dropped the LP fish boxes overboard again. Doc and Steve got in to freedive and set the boxes up. The lemons apparently started to get a little frisky as the sun went down - buzzing the freedivers with close passes. A few gentle kicks and the sharks started to behave again. Doc and Steve got out of the water and we prepared a large dinner with our fresh catch of the day as a centerpiece. So far things were going really well. The sharks were cooperating, we had collected some DNA samples, and the monitors were attached to the bottom and listening for sharks. The weather had also calmed down and tomorrow looked like it was shaping up to be the best day yet. After dinner, Steve and I hung out on the back deck watching the lemons glide in and out of the eerie blue light located on the hull of the vessel. When we first went out we got really excited as we observed a HUGE black shape - only to realize it was the shadow of a lemon projected onto the light sand on the bottom. I was definitely tired but ready for the big day to come. We have saved the best for last - actual lemon shark captures for tagging and transmitter attachment.
June 10, 2008
Daily log by Steve Kessel
Waking up to plenty of lemons
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Doc woke me up with an excited squeal at 06:00 in the morning shouting "come look at this!" I jumped up and ran out back to see flat calm seas and 15 big lemon sharks just hanging out behind the boat. "It's gonna be a good day," I thought to myself. We fed the sharks for a little bit then got to work. We wanted to get some picture of the sharks with the bait boxes so we brought them to the stern of the boat then loaded them inside and out then dropped them down. I was slightly nervous at first, as all the lemons charged towards the boat in full feeding mode. By this time approximately twenty big lemons were darting about, and we were only a few meters away from the bait box. However, the lemons were being surprisingly docile, as they were brushing up against us as they swam by. Doc figured out that the lemons loved the electric field being given off by the metal poke pole he had brought down for protestation. They would bite at it and he could lead them around...he was in heaven. There was also a big tiger in the area, and would gracefully glide in and out of sight. It was huge - with a big fat belly, and we guessed that she have been pregnant. Doc then (without me realising) went to the surface and got a couple of fish to put on the end of the pole. He brought them down and tried to feed one, but I guess it just knocked it off the pole, because I lifted my fin then put it back down, but met resistance. I turned to look and I was standing on the head of a 260cm lemon. I lifted my foot and it literally shoveled me out of the way with it's snout. I was puzzled, but then realised what it was doing when I saw it take the bait lying on the sea bed in front of me. Doc then lead another chomping at the pole right in front of me. I reached down and put my hand on it's back, stroking it like a dog.......this is awesome!!!
Doc feeds a lemon with a baited pole
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The next thing we wanted to do was to get pictures of the sharks around the monitors that we had set the previous day. So we positioned the big boat so that the monitors were just off the stern, and then dove in with a lastic bag full of bait. It was my job to look after the bait and this was one of the best experiences of my life. I knew that if the sharks got to the bag of bait it would be really bad for everyone, so almost the whole time I was laying on it like it was a grenade and I had decided to sacrifice myself to save the rest of the platoon. The action started heating up, and at one stage as Doc was enticing the sharks with the metal pole he almost lead one, teeth ablaze, chomping right at my face to within a few inches. I was surprised but managed to dodge the shark with all my facial features intact. The sharks were swirling around us now, and I got over the close-call pretty quickly. The defining moment of the whole day for me was when one big lemon, that could clearly smell the bait pinned under my chest, swam straight at me and didn't look like backing down. I had to make a decision, as I thought it would be really bad for it to get under me and hit the bait. So I reached out and put my hand just behind its mouth and pushed its head away to change its direction. To my delight and relief it complied and doggedly swam off a few meters.
Working up a lemon by the M/V Dollie
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The dive was one of the best I've ever done, it was a shame it had to end after about an hour. There were sharks everywhere you looked and they came in so close that not only could you and did you have to touch them, but more often than not they were touching you. Climbing all over you in fact, but they NEVER bit, NEVER. They are incredible. So people if you can lay an a load of bait in water where there are 20 big sharks swimming around you and not get bit, what danger do they really pose us...you have to question the fear here. I was even able to periodically take pieces out to feed them and still not get hit. INCREDIBLE. Last thing on the agenda was to catch and transmitter two sharks and we just managed it. It proved to be a very precarious endeavor, as we were working up big nine foot long lemons in a monstrous 10 foot tender - just barely bigger than the sharks. Somehow we managed it without getting killed or sinking the boat. Don't ask me how, because on numerous occasions I thought both might happen. The second shark took a while to catch and we had almost completely run out of bait. We were able to snag a few jacks with a rod and serve up some fresh bait to finally hook the second lemon. The tagging, measuring, and transmitter surgeries went smoothly and we released the second shark just before sunset. We returned to the boat, cleaned and stowed gear, and sat down to a well deserved feast. The trip had been a resounding success. Doc may have said it best..."This has been the greatest day in my 50+ year career of studying lemons sharks..."
June 11, 2008
Today we got up early and pulled the anchor. We left Tiger Beach and headed over to Florida on calm, flat seas. I looked fondly over the area as we pulled away and my only thought was wondering how soon I could find my way back to this amazing area. It was an amazing three days and the experiences I had here were intense. They are vividly burned into my memory and captured by my camera. I spent the trip back home looking through my pictures and reliving my dives in my mind...
I will always remember the TB lemons...
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