Interns help tag a great white shark

November 26, 2012 by dyertrust

great white shark trackingOne of the most exciting events that an intern here gets to participate in is the tagging of a great white shark. On the morning of 3 November, we were asked to perform this task. Oliver Jewell is the manages our intern group and is also one of the resident biologists studying shark movements and the proposition of home ranges. Our intern team that day was comprised of Matt Smith, Tess Mahoney, Giovanni Vasser, Dawn Watson, and Christopher Algero. Also with us that day was our technology specialist, a highly skilled and fearless man named Ed. We gathered early that day to prepare the vessel, Lwazi, for her brief expedition. Once she was loaded with chum, had her GPS and radio attached, and the tracking hydrophone and computer were on board, Lwazi was driven down to the quay and launched.

After chumming for what did not seem like a very long time our first shark arrived. She was a large shark and would not be our last large shark of the day. Not 20 minutes had passed after her arrival before we were surrounded by sharks of sizes large and small. The duties at this time were important as those on their positions were at their best this day. Tess Mahoney and Dawn Watson were in the crows nest on the lookout for sharks, their words were relayed down to the people on deck so that no one was surprised by a shark. Listening closely to Tess and Dawns warning were Christopher, Matt, and Gio. Chris was on the bait line, it was his job to entertain the sharks and direct them closer to the boat when the time for tagging had come. Ed and Matt were on the chum line, their slosh of fish mush poured expertly from the bucket brought the sharks to the boat. Gio was working the decoy line, his duty was similar to Chris but with a chewy fake seal. Finally last but certainly not least was our skipper and team leader, Oliver Jewell.

After chumming for some time the waters had not emptied but cleared shortly of sharks. The bait line and decoy lines sat still on the surface. Shark, Rita took advantage of this fact. Her first strike was fast and powerful but Chris withdrew the line in time before she got to the bait, just as he thought the bait was safe she swiftly turned about for a second and immediately a third strike. After much deliberation Oliver decided to tag this swift shark.

Her shape was unique and intrigued our crew. She had a much sharper nose and was thinner than most great whites. This is most likely due to her eating pattern but nonetheless was a noteworthy trait. She had several injuries including a deep cut on her caudal fin. Another shark that had scars all around its face, aptly named Maori, was also near by. This same shark and several others had also attempted several times to investigate the chum bucket along with its accompanying crew to no avail. No avail other than to scare Ed and Matt that is.

When Oliver had prepared himself and his equipment, he stepped up to the proverbial plate and to the literal railing. He instructed Chris where to bring the shark when she passed again. It was just this moment that Tess and Dawn had spotted Rita rising from the depths as if she was some aqueous phantom from a Lovecraft epic. She approached the bait and in as much time as it takes me to write the end it was all over. Oliver had tagged her just beneath her dorsal fin. The crew took a brief moment to celebrate their successful tag and exchange high fives but there was still work to be done. We put away the chum and chumming supplies to being tracking.

We then tracked Rita for five more hours relying on the energy burst we had all received from the tagging along with some cheese and tomato sandwiches that had been prepared by the kitchen staff at the Great White House for us to eat. The tracking went swimmingly well although in later days Rita would prove to be a tricky lady to track in the coming days, but that is a tale for another time.