One of the great things about living on Stewart Island is that opportunities can arise that don't seem to occur in normal life. On Monday 29th March, a beautiful, sunny, autumn day I was out on the Department of Conservation (DoC) boat, skippered by Barney. Also onboard was Clinton Duffy, probably New Zealand's leading marine biologist, who is studying the Great White Sharks that spend a lot of their time in this area, attracted by the huge New Zealand Fur Seal rookeries on the surrounding islands of Stewart Island.
Clinton has been studying sharks here and around the Chatham Islands for about 4 years. A lot of these studies mean getting up close and personal with these often misunderstood animals.
About 3 hours of drinking coffee, the waft of rotten tuna heads floating off the back of the boat and minced fish thrown over the side at intervals brought the bird life. Northern Giant Petrels, Shy and Buller's Albatross, Sooty Shearwaters, Black- and White-fronted Terns and the bulky shape of a Brown Skua. I was happy just snapping away with my camera, when the albatross I was taking a picture of, disappeared rather quickly. Out the corner of my eye a big dark shape appeared just below the surface of the water, the apex predator had arrived and I was no longer a Great White Shark virgin. Seeing one, that is.
Clinton and his team said, "Oh it's just a small one", as they guestimated it was two and a half metres long. It looked big enough to me. To ID the shark, an underwater camera on a pole was put over the side, operated by Kina.
Sharks, like dolphins, have unique dorsal fins with scarring and patterns on the side of their bodies. This turned out to be a young male the team had not seen before. He was very interested in the bait and spent 45 minutes or so just circling the boat. I found it hard not to quote movie trivia, "You're gonna need a bigger boat ...".
One of the first things Clinton told me was that the dorsal fin is very rarely seen slicing through the water (as depicted in the movies) although when they migrate the dorsal fin does come out more. Most sharks around Stewart Island migrate to north-east Queensland around the Great Barrier Reef in Australia.
The team decided to put a spot transmitter on the shark, which would send a signal to a satellite every time his dorsal fin came out of the water. It's hoped that the transmitter shows important data such as the migration route, depth and water temperature. But this meant actually catching him. So a fish head was put on a large hook with some buoys attached to the line, and it was thrown over the back of the boat.
The next few seconds were stunning. Frustratingly, none of it was caught on film. The shark took the bait, instantly diving taking the buoys with it. The buoyancy meant he was going to come up quickly, which he did - completely breaching out of the water, which even Clinton and his team said was bloody rare!
The shark gradually wore himself out and the team brought him alongside the boat. With the boat moving slowly forward all the time, so that water passed through the shark's gills, a rope was put around the tail and the shark's head was held tight against the side of the boat. It became apparent that I wasn't going to stand back and take photos. All hands were needed on deck to make this process quick and less stressful for the shark.
Clinton drilled through the dorsal fin and attached the transmitter (about the size of a pack of playing cards) with nuts and bolts. A sample of DNA was taken and the shark measured; he turned out to be 2.7 metres long, 8 feet 10 inches in old money. SMALL my arse! Females are normally bigger and the average size of a female around Stewart Island is 4.8 metres long.
Time to release the shark. First the tail is released and the hook in the mouth is cut with bolt cutters, leaving the tip in the mouth to be pushed out naturally. The cold black eye that's always associated with great whites, looked at us as he disappeared into the deep. Wow! I hope he's got the memory of a goldfish.
We went looking for another shark in a different area but with no joy. Just one lone juvenile Yellow-eyed Penguin appeared for about an hour, and then it was time to head for home.
Ulva Island
Autumn has arrived in my office. Birds are calling less, berries are appearing and birds are feeding up for winter. Yellowheads are still feeding young, as are the Saddlebacks. The damp spell at the end of March seemed to bring out quite a few kiwis during the day, which is always nice. The first one I saw was a huge female that slowly walked away from us after twenty minutes of good views and the one last week was a smaller male that started off about five feet in front of us, but after about ten minutes he melted into the bush in the background. Happy clients, happy Matt!
Thanks to Jules for revamping my website!