Sunday, January 22, 2012

Third Times a Charm

Around the resort of Monkey Mia my research team is known as the “Sharkys” and until recently that title has been a bit misleading.  The main goal of the Shark Bay Ecosystem Research Project is aimed at determining the specific effects of the Tiger Shark, the top of the food chain, on all the other trophic levels that feed into it.  However I had not yet had the chance to work directly with a shark and felt as though I had not earned the right to be called one of the sharkys.

That nagging feeling of undeserved distinction has been a small but constant grain of sand in my mind until recently, when it was washed away as we caught 11 sharks in a single day.  We woke at 6am prepared for a long day.  All the gear was ready and we were raring to go.  Out on the water we set the lines one at a time ensuring that each had a good chunk of smelly fish on the hook.  We use big fish for bait because we hope to catch the big sharks though any size will be processed, tagged and released nonetheless but the big ones are where all the fun is.

Spinner Shark  (Adriana Weil)

The first couple days we spent sharking were complete busts.  Each day the wind picked up and forced us to abort the mission early.  Each day we caught a single Tiger Shark, and each time it was tangled in the ropes and potentially stressed out so we simply cut them free instead of putting them through the added stress of processing.  The last thing we want to do is harm or kill a shark.  We are only here to observe and record by putting as little influence as possible on them.  We are required to catch them to in order to obtain blood and tissue samples but these are minimal and efficiently carried out so that we can release the animals as quickly as possible.  Most sharks are unable to push water through their gills while sitting still and must continue moving in order to maintain oxygen levels.  While taking their measurements we idle the boat forward to keep them breathing which helps to keep them calm.  Nobody likes holding onto an unpredictable panicky shark.

Great Hammerhead on the line.  (Tyler Roberts)
On this day, our third attempt, we hit the jackpot.  First there were a couple average Tiger Sharks, about 2 meters give-or-take.  Then we found a Spinner Shark on the end of one line which was a bit exciting.  It was calm but at least we were getting some variety now.  After that it started to pour sharks.  We had to scramble to get from one buoy to the next with shark after shark. We came to one spot where it appeared that the buoy holding the line must have floated off because it was nowhere in site.  All of us were looking around with eyes fixed on the horizon for a white spot that might indicate where our line had gone.  Then right next to the boat the line floated up into view through the milky green water and just underneath the buoy was very large and very dark silhouette.

The Great Hammerhead (Adriana Weil)
We pulled up the line to see the massive head of a Great Hammerhead jut up through the surface of the water.  My heart jumped to realize how large of an animal we had dangling from a chain not more than 4 feet from my hands.  I've watched plenty of nature shows to know how big these animals get but first hand knowledge is not the same.  They are awe inspiringly large with power that goes far beyond what I can imagine.  You may hold the line of the shark in your hands but that faint illusion of control is quickly lost when it decides to dive or even just swish its tail a bit.  You are wrenched in whatever direction it takes you. Sometimes you can hold onto it though by doing so it drags you and the boat with it and sometimes you drop it because nobody wants to spend even a few seconds alone in the water with a 4 meter shark as round as a refrigerator and mouth as large as your torso is long.
4.08 meter (13 foot) Tiger Shark   (Adriana Weil)

This particular shark was not just large but she was quite feisty as well.  Safety being number one, we decided against going through the full procedure and took some quick measurements, a small fin clipping and released it.  That one took a lot out of us and we were only about halfway through the day.  With the weather cooperating for once we kept vigilant and moved on down along the lines to see what else we had hooked.  A few more average Tiger Sharks, one more Spinner Shark and then we hit upon half sunken buoy.  We had a pretty good guess at the size of this one from our previous encounter.  It was sure to be a beast and upon later measurement was over 4 meters long, just a hair longer than the Hammerhead.  This one was a massive Tiger Shark but much more docile than the Hammerhead.  I got to control the head during our processing.  It was a hell of a workout just holding it up alongside the boat.  By the end my hands were cramped into a claw shape from gripping the chain so hard for so long.

By the end of the day we had broken Kirk's previous record of 9 sharks in a day with a whopping 11 including 2 full on beasts, 3 different species and one little baby Tiger Shark on the last hook of the day.  I feel good about the data we collected and am now quite proud to be called a Sharky.

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