On our first day of our Oceans Research internship, the other new intern for the month of September 2015 and I had a really exciting day that included meeting the boats and also a trip to the local vet clinic to learn about suturing.
We started off the morning with lectures from two of the field specialists – one from Olivia on data collection and entry, and another from Justin on sea fishing, boat skills and safety. Since we had our harbour passes sorted, we were able to gain entry into the dock and saw the boats that are used during internships – Lamnidae and Mako. I loved the look of the viewing platforms and absolutely couldn’t wait to get out on the water on them. After a knot-tying class, we headed back to the backpackers for lunch and were told that we had something exciting planned for the afternoon – we were heading to the vet clinic to accompany Justin and Ralph (one of the PhD candidates working with Oceans) to a suturing lesson.
Suturing is an important technique used when working on projects that involve surgically implanting acoustic tags into sharks. Acoustic tagging is an important method used when investigating the movements of sharks so that more can be discovered about their ecology. The method we learned about involves carefully making an incision on the underside of the shark, inserting the acoustic transmitter and suturing it closed, sprinkling antiseptic powder on the wound and applying water to seal it.
We watched and listened carefully, and took note of an important recommendation from the vet – that it is best to use nylon or another material that is not wound or plaited so that bacteria cannot get into the gaps. We were taught a suturing technique that was considered more secure than other examples we were shown. Since tags can be quite pricey, it definitely makes securing them properly an important factor to consider.
We were told that the technique would be used with anaesthetic and also while the sharks were upside-down in tonic immobility. While we were understandably not going to have the opportunity to suture on a live shark during our internship, we had a lot of fun practicing the technique on pieces of leather during our spare time that afternoon.
On our way out of the vet clinic, I was curious about the other animals that come through and the vet ended up showing us a baby loggerhead turtle that was being looked after.
The following day, we were scheduled for our first chum trip. I was finally about to meet the Great Whites that had fascinated me for so long and was eager to have the opportunity to form an opinion about them from my personal experience!
It was a beautiful day and we departed on Mako, after gaining permission via the radio from the harbour master. We travelled past Seal Island which really surprised me with how it smelt. I wasn’t expecting an island full of seals to smell nice but this was really something different. We reached our destination – Hartenbos and I was eager to get started so went up towards the bow and helped a more experienced intern (who had already been with Oceans for two months) to sort the anchor out.
After we had anchored, a flag featuring the outline of a shark was tied at the top of the viewing platform and we started chumming. Chumming involves putting a bag of frozen sardines into a rectangular tub and using a bucket to move seawater into it to defrost. We were also given gumboots to help speed the process up by stomping on the frozen mass. We would then ladle the bloody liquid out into the water in the hope of attracting sharks so we could collect important data on them.
We saw our first shark just under an hour and a half after we anchored, and it was an incredible encounter I won’t forget.
I looked in awe at this beautiful animal that so many of us have been told is a dangerous monster and spent a few moments just appreciating the grace of this amazing, perfectly adapted creature as it swam alongside the boat. I was on data collection for our trip so was listening carefully for an estimation of length, if possible – the sex, any deformities or pigmentation and took photos and videos once I got the chance.
We used a process called bait roping in which either a field specialist or experienced intern would throw a tuna head (or tail) that has been secured to the rope out into the water, off a special platform at the stern. This was done so that the intern on photo ID duty is able to get close up photos of the dorsal fin, which is a method currently used to differentiate between individual sharks. When a shark would approach the bait, the aim was to quickly move it so that we avoid letting the shark take the bait and allowing for us to get the shots we needed.
We saw two beautiful sharks during our first trip and were lucky enough to see the underside of one when a female came alongside the boat, thus getting a practical lesson on determining gender in Great Whites. I actually found them quite peaceful to watch as they swam by and witnessed that they are quite inquisitive after watching the second individual continue to hang around areas of the boat away from where the bait was.