Alan Foulis writes about his experience as a researcher working on shark and tuna longlining vessel’s off South Afric – Story from canyoufathomit.org
It was in the company car on the way to Richards Bay that it hit me, “I was going out to sea with a bunch of men for an extended period of time, none of whom I knew”. The anxiety was bubbling below the surface as we left for sea on my first trip on board a commercial tuna longline fishing vessel.
The days that followed saw me experience wild seas, big fish, and heart burn. Including that trip, I have been on three fishing expeditions since. Two were on board tuna boats and more recently I went out with a shark longliner, the latter being a lot more challenging both physically and emotionally.
But before I delve into my experiences on board and the resulting conclusions about the status of shark populations off southern Africa, let me explain what it is I am doing and where. I am currently based at the Oceanographic Research Institute in Durban where I am doing my Master of Science degree in marine biology. My project looks at two things: firstly, what sharks are being caught “by accident” (I will explain the inverted commas later) in the tuna and swordfish longline fishery in South Africa, and secondly a full biological on the shortfin mako shark (Isurus oxyrinchus) which will include how long they live, how fast they grow and when they mature sexually, to name a few. It is my hope that once I have completed my project we will have a much greater understanding of what is happening out on the deep blue and allow us to manage our sharks more effectively so that they do not disappear for good. So, with the above in mind, I set off on my three trips to find out things like; what types of sharks are being caught, how many, where, when, and what do the fishermen do with them.
Now, the reason I put “by accident” in inverted commas earlier is because very often they are not and instead there fins are removed to be sold as an ingredient for shark fin soup. This dish is considered a delicacy in Asia and when ordered it shows that you are successful and wealthy. As a result of the economic resurgence in Asia during the 1990’s there was in increase in wealthy people and therefore an increase in the amount of shark fin soup being ordered which in turn resulted in the decimation of shark populations worldwide.
But the question is how are our sharks handling it?
Honestly, the answer is: OK… for now. The pressure on our open ocean shark populations is not as heavy as it is in other parts of the world but it is growing all the time. Increasing pressure from foreign vessels just outside our ocean – borders (it is 200 naughtical miles from any point along our coast, and is called our exclusive economic zone) together with our own vessels is going to have a detrimental effect at some point, but where is that point or more importantly, when! My two trips onboard the tuna longline vessel was an experience I will never forget from both an interaction and fishing point of view. But from a shark point of you I found that, in general, they didn’t want to catch the sharks. This could have been purely because I was on board but it seemed as if they genuinely didn’t want to because they saw them as a pest rather than as a source of income. The only species they did keep was the shortfin mako because its meat as well as fins is valuable, whereas for most other shark species it is only the fins that fetch a decent price. The most common species caught on the longline was the blue shark (Prionace glauca) which was alive when caught (most of the time) and cut loose next to the boat. So after my two trips on board the tuna boats, I felt that there was a far greater threat to sharks out there than our tuna longline boats as the number of sharks caught and subsequently released was not excessive.
The shark longliner was a very different story. My most recent trip, as I mentioned earlier, was on board a shark longliner for a total of 20 days at sea. In this time, we caught over 50 tonnes of sharks which consisted mainly of shortfin mako and blue shark: 41 tonnes of mako and 15 tonnes of blue shark. But what struck me most about the operation was just a basic lack of knowledge. You see to these fishermen sharks are just another fish in the ocean, a fish which is seemingly as plentiful as other types of fish but makes them more money. They have no concept of the sharks’ life history strategy (how they live and reproduce) or how their fishing is affecting the species. It was my mission to at least impart some knowledge to the skipper and crew of the vessel whilst I was on board without aggravating anyone.
The first few days were an absolute hurricane in my life because within 24 hours of being on board we had caught over 4 tonnes of shark. Hmm wait, let me quickly explain how a longline works before I carry on. A longline vessel uses just that, a long line… a very long line. The long line is called the main line and the length ranges from 60 – 100km in length. Along the line at 20m intervals there are shorter lines called droppers which are between 20 and 30m long. Each of these droppers has a hook and bait attached to it. The line is put out at night and collected first thing in the morning. This is called the shooting and the hauling of the line. The shoot takes about 4-5 hours and the haul, depending on the weather, amount of fish, and any entangled line, will take between 7 and 12 hours. This happens every day and night weather permitting. Along the line there are buoys to keep the line afloat as well as radio buoys to make sure the skipper can find the line the next morning as it drifts. There are 10 radio buoys in total and this means that if the line is cut at any point (by another ship or strong current) then he can sail to the nearest radio buoy and pick up the line from there. Ok, are we on the same page now… good ☺ So that first night we set a short line and caught a lot of sharks. The deck was a blood bath and there were bodies and fins everywhere.
Emotionally it was extremely hard to watch animals, that I love and have a passion for, get slaughtered for some soup dish in Asia because they have a need to express their wealth to other people. I had a hard time concentrating on my work but after two or three days I had to switch off and just get on with what I had to do for my MSc and remember that I have to observe not interfere. They kept everything whether it was big (3m) small (<80cm) it was kept. But after a week of getting to know the skipper and crew and trying to understand their viewpoint, they started asking questions and I started talking about the sharks more. I told them how slow sharks grow and that they only have a few pups, depending on the species. In addition, mako sharks only reach sexual maturity at around age 8 and 18 for males and females respectively (that’s a flipping long time considering it takes tuna a couple years). After chatting to the skipper he agreed that it would be ok to let go any mako sharks that were under a 1m in length. This was a massive step in the right direction and the crew really warmed up to the idea.
Whenever a small shark came on board the crew would ask me if it was too small and if it was they would help me get the hook out and release it safely. But just to give you an idea of the fishing pressure these sharks are facing out there, there were sharks (often!) that we would catch that already had 2 or even 3 old hooks in their jaws. I mean the chance of the same shark being caught more than once or twice in the open ocean is miniscule yet it is happening regularly which shows that there are a lot of hooks in the water! We were out at sea for a total of 20 days and in that time I saw thresher sharks, bronze whalers, mako’s, blue’s, pelagic stingrays, dogfish and a moonfish, and I am glad I did because in the back of my mind is a dark thought that if we do not try harder to save all these animals, they will disappear forever.
At this point our oceanic sharks are still out there and still playing their very important role in their ecosystem, even if it is at lower numbers. The time however, is running out and if we continue now as we are then there is going to be a disastrous effect on the ocean as we know it.
The management of sharks in Southern Africa is much better now than it was 10 years ago but we still have much to improve on and even more to learn.
