Saturday, December 15, 2007

Shark Chronicles 001 - The beginning of a new era...

Welcome to the beginning of SAMPLA.

There are many marine predators that SAMPLA wishes to bring out of their realm and into ours through the tools of research and exploration. For now, the great white shark, Carcharadon carcharias, is our main focus.

The first shark trip SAMPLA’s founders took together (sadly without Steph at that point) was in June 2007.
It was a ‘routine’ DNA collection trip and the swell, combined with a dodgy meat pie, proved to be more threatening than the sharks. We sat for an hour, a greasy slick emanating from the boat, the only visitor a box fish that nibbled on flaked tuna, but no sharks. No sharks, one hour, we shifted (a patient group?).
The first appearance of a shark is always exciting. A slight shift in sea surface colour is sometimes the first sign, but this time Ryan (and Fiona, my wife) noticed the gulls were not so comfortable sitting on the water, as well as a corresponding ‘change in tune’ to a shark squawk. A small shark arrived, just over 2 metres, and flirted with the bait. Small shark or not, we wanted some of his DNA.

Collecting biopsy (flesh) samples for DNA analysis involves a chummer (who makes the environment adjacent to the boat irresistible to sharks). The chummer gets covered in oily fish and continues to smell for days after a trip (some times clothes are unsalvageable). Then you have the bait rope handler. Rather like a matador luring/evading a bull, the bait handler tries to lure the shark as close to the back of the boat as possible, without the shark getting the bait. Finally, you have "Ahab" himself (not very politically correct), the harpooner. He waits like a darter, for the ‘money shot’, the exposed flesh at the base of the dorsal fin. Before screams of ‘how could you’ fall on the harpooner, it is only a small plug of flesh, it is vital in getting geographical patterns of relatedness in populations, and the shark often returns afterwards to look for the bait (i.e. it didn’t hurt that bad).
We got seven biopsy samples from seven different sharks that day – not bad. A short trip and a short passage of writing, the story of SAMPLA’s exploits will continue…

TOBY

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