There is always something to learn…
by John Curnow on 9 Mar
Did you know that broadbill swordfish have a gland near their eye that secrets a special oil that is thought to make them even more slippery through the water? Until about a year ago, no one did! Also, did you know that the Oceanic White Tip Shark has special sensory structures in its head that act like a natural GPS utilising the earth’s geomagnetic field to locate itself in our vast oceans as it travels around the globe? Bet you didn’t.
Amoukura was one of the largest vessels present and was used for the filming of a new ad for Penn. - 2017 NSWGFA Interclub sponsored by Pantaenius John Curnow
So you could imagine how excited one of the scientists present for the 2017 NSW Game Fishing Association’s Interclub tournament was when he learned that one of 130 boat fleet participating was bringing in a sample of that very specific species for him to analyse. Given their expansive migratory patterns, having one to study is almost unheard of, and being taken only a couple of hours before it was brought to the weigh station just made it all that much better.
His own story is almost as interesting as that of the fish he studies. He was born on the French island of Reunion in the Indian Ocean, in between Mauritius and Madagascar, close to the shores of Africa. Arnault Gaulthier is a PhD student from the University of Queensland working on the electro-sensory system of sharks and rays. “I have had the chance to work on quite a few exciting sharks over the course of the weekend. The Oceanic White Tip is one of my favourites, and no one has really ever studied them before.”
“Looking at its sensory system is very exciting and to assesses its overall function. It can detect both prey and predators, and communicate with other animals to some extent. Most interestingly, as some people put it, it is also a kind of internal GPS that they use to navigate through the earth’s geomagnetic field. These are very rarely caught, including in tournaments like this, where most people have not seen one in more than ten years. Accordingly, access to them is nearly non-existent, and we do not know just how different they are to any other of the species we have come across so far. To be able to study them now is incredibly exciting and promising.”
Dr Julian Pepperell, an independent marine biologist and author, and after 40 years of work in the area is an expert on large pelagic fish. He has been independent for 25 years, and does joint research with universities all over the world, supervises PhD students all around the country, and has international projects, as well. He also works with the CSIRO, most specifically on billfish, tuna, and sharks.
“I also train students who then attend many tournaments, where sex, weight, various measurements and location are gathered, and collect the all-important tissue samples. Those samples now number over 1000, and act as a huge archive. In addition to being available for specific project work, they have been essential to around 50 studies that have been undertaken, all over the globe.”
Pepperell began with the NSW Fisheries Department, including running the tagging program, which is now 40 years old, itself. He goes to a lot of tournaments, and has been at the NSWGFA Interclub each and every year since 1977.
“We have gone from no tags in those days, when maybe 230 small black marlins were caught, to today, where it is virtually all of them (95%+) that receive a tag here in Australia. The other benefit is that we now have samples from various species going all the way back to those days, and so can supply them for all manner of studies here and around the world”, said Peppered.
“Back then nobody knew anything about black marlin. The tagging program now has records of 65,000 tags over that period. We now know that Black and Blue Marlin live for up to 20 years. Even at one year old they are 30kg and 2m long, so they grow very quickly, having hatched from an egg the size of a pinhead, and this includes striped marlin too.”
“So at 4-5 years they will be around 130kg, and the only reason we have this sort of data is from all the research over the years, greatly assisted by game fishing tournaments. At the same time as finding out exactly what that gland in swordfish does, we are now also going to see if also exists in marlin.”
“Because game fish are big, people think they are old, but a lot of pelagic (open ocean) species grow very quickly. The Mahi Mahi is a classic. They only survive for up to three, maybe four years, and at age two they will be something like 25kg, and around 1.3m long!”
“Conversely, some of the sharks are very slow to grow, which we know from all of the samples, and so they need looking after more so than, say, marlin, which can reproduce their numbers somewhat quickly. All of this material is what is used to determine the sustainability of fishing, both recreationally and commercially”, said Peppered.
“These are cosmopolitan (worldwide) animals. We used to think that Black Marlin for instance were all the same and both sides of the Pacific. If they are criss-crossing over large distances, it then has implications for the management of stocks. Now even our own tools are improving – 10 years ago the DNA testing was not as sophisticated as it is now. Accordingly, it has now been shown that there are separate populations between areas, and a study of some 80, non-lethal fin clips from both Western and Eastern Australia has proven that they are distinctly different. Not a different species, but races, if you will.”
“So they intermix to some degree, and we have the records to show that, but they must come back to their specific spawning areas. Of the black marlin tagged we have had more than 600 recaptured, mainly in the southwestern Pacific area, so the data is there for us.”
“I think tagging has helped to get people interested in research. Anglers are now accustomed to scientists on weigh stations, and annual reports show what they have helped to generate. It is a partnership between us both, and donations from the private sector also show the fisherman are committed to the long term sustainability and knowledge that the sport provides for.”
Pepperell then commented, “There are always new discoveries, and this is what makes it exciting, for these fish are hard to study by virtue of where they live. Take the new oil gland. Now that we have found it, almost unknowingly, it has to be determined if the oil goes all over the body, and what more can be learned under the high-powered electron microscope. This and 3D imaging has been a real boon for us, and so different from the days when the material was simply squashed under a microscope slide.”
There have been projects that spread the base even further. One example is a University of Queensland-based archaeology student, Karene Chambers, working on a site in Granada in the Caribbean where remains of tuna caught 1000-1500 years ago have been found. The bones were the key to determining what species and what size the tuna were. The indigenous population stopped fishing when the Spanish arrived around 1450AD. Sustainability back then and now, along with other questions will be hopefully solved, just by knowing what species and sizes were being caught through this time period.
“So yes, a little tuna caught here off Port Stephens is helping out there. Karene is thrilled, and Arnault will take them back to her with his own material, as they are from the same University. We collect the whole fish, she takes the flesh off and sees the exact skeleton and then compares it to the ones that have been dug up from back then”, explained Pepperell.
Another example is the medical research department at James Cook University, where they are looking into fish allergies for humans. This Post-Doctorate study is taking samples of certain species only, analysing the allergic compounds between them, so as to determine which ones can be eaten safely. This study needs the freshest of fish to be accurate, and so the NSWGFA and the scientists are helping to make it happen.
Yet it is not all about the fishing, or the science, either. Dave Bye has been attending the NSWGFA for 46 years now, and remembers when Dr Pepperell first appeared. He’s from the Tahlee Ministries, which is right up the other end of the bay we all know as Port Stephens. He was the one who recognised that there was fish on offer in the early 70s, and he saw a way to feed people. No doubt his early days in post-depression Australia played on his mind. At the beginning, both the Ministry and nursing homes benefitted from their collections, but in these litigious times, it is now only their community that reaps the gifts of the sea each year.
He’s softly spoken, laconic in a very Australian way, and clearly, a very decent human being. Of his journey so far, he said, “Seen a lot of fish. Over the years it has certainly changed, but we are glad for all the produce we can eat. The rest is turned into fertiliser, demonstrating a 100% usage factor. Many say that frozen fish is no good after a few months, but we use it throughout the 12-month cycle. It is still good. We even make smoke fish from the goodies, as well. It is sad that we cannot distribute it anymore, because being boneless and all, it was of great benefit to the wider community.”
“Over the years we have had a lot of people come through and assist with all of the activities here on the weigh station. It certainly has been a different and rewarding experience for many of them. We feel it is a great way to connect with the greater community and show that we are normal folk and just have a strong spiritual devotion with our faith. Our location was where the whole area got opened up in 1826 by the Australian Agriculture Company, and they’re still going in the Northern Territory and Northern Queensland, and very heavily into beef production, which has nothing to do with fish, obviously.”
“So yes, very happy to receive the donations from the all the anglers. We eat what we can, and the rest becomes fertiliser. In some countries they eat Tiger shark, but not us. Equally some countries cut the fin off and throw away the shark, whereas we eat the shark and mulch to fins for use on our organic garden. So we think it is a great added service to both the clubs, scientists, and the wider community”, said Bye.
Word had got out, or more precisely was extended, and Howard Greenyear from the Bruderhof community of 250 souls in Inverell (Danthonia) was one of their members who attended for the very first time. “There aren’t any fish out there, so we were keen to get down and see some salt water fish, and maybe even bring some home.” They did, especially so due to the assistance of Tahlee.
Bruderhof has been in Australia for 15 years, and Howard’s accent is testament to the German, Spanish, English and American born individuals that make up their wider group. Howard himself was born in Sussex, UK, and spent a lot of time in the USA with their communities, which number 27 in total on four continents. So perhaps, and over time, the word will get out to some of those and they too will be at local tournaments making use of the catch.
All in all the fishing went well, even if the overall numbers were less than in most other years. You certainly would not have known it by talking with the participants, either, for their smiles were as infectious as their love of life in general. They went out, mostly to the continental shelf, in everything from blinding sunshine and millpond like seas, to significant lumps and pouring rain, such was their enthusiasm.
So despite the challenges afforded by the weather, 54 Marlin (all species) were tagged and released, and just four brought ashore for samples, eating and also donation to the ministry. The largest of which was a151.9kg Blue Marlin. 22 of the impressive, and fantastically sporting Mahi Mahi were tagged and released, with four of those also coming ashore. A massive 26.1kg male was a delight to see, and for those lucky enough to be at the table later, a complete treat too!
There were 10 Shortbill Spearfish tagged and released, and no captures. 11 of the fast swimming striped tuna were tagged, and also a handful brought ashore for the scientists, as per their request. Two of the ultra-quick Wahoo were tagged and released, again with none captured. That leaves the sharks. One of course was the long-ranging Oceanic White Tip that helped out both the scientists and the ministry in the end. The largest fish weighed for the tournament was the 256.1kg Tiger Shark. In all, five sharks of various species were tagged and released, with three coming ashore. Two of those ultimately were donated to the ministry, which means it was virtually a 100% usage rate across the board.
As always, there was many a highlight. The high-speed sailing and diesel cat, Gloriana, caught the winning Marlin on a reel that they won in this very tournament in 2013, which absolutely shows the support of sponsors is a valuable thing. They worked hard for six hours to be able to enjoy their efforts.
Another had to be the Ladies’ Day, which was held under inclement weather. You would not have known, for they added their own brand of colour and their onshore celebrations were also very exuberant. It is worth noting that 11% of the Game Fishing Association of Australia’s members are female, and this equates to something like 1100 individuals.
Possibly one of the least known facts is that one boat all on its own has been auctioning itself off for a one day trip for the last ten years, and as of now they have generated more than $750,000 for cancer research.
Winners were as diverse as the 130-boat fleet. There were male, female, junior and small fry categories of angler, and they all seem to appreciate the new four-day format that encompassed one weekend, not two, as per previously. Ultimately, you cannot help thinking that we, the greater community could well have been the biggest winners, given the large crowds that attended the weigh station and all the material that the scientists were able to gather over the event. Most probably those that got to enjoy their Mahi Mahi had the best time, probably with the exception of those that made the ultimate donation to feed the Tahlee Ministries.
Pantaenius Sail and Motor Yacht Insurance is proud to be back for its second year as a major sponsor of this terrific event. Not only do all the crews have a wonderful time out at sea, the fact that so much is learned, the vast majority of fish are tagged and returned to the sea, and that the Tahlee Ministries processes much of the catch for either food or fertiliser, just shows how sustainable and important all the activities are. Of course, any event needs volunteers and the Interclub relies on so many. Well done to them for making it all happen so smoothly.
If you have a game boat from trailable to large sportsfisherman, aluminium plate or fibreglass, then you might want to investigate the only true, marine-originated, agreed value insurance policy from the crew that know boats. Go to www.pantaenius.com.au or call +61 2 9936 1670 today, and see why everything from superyachts to global cruisers, game boats to racing yachts select the all-risk policy that only Pantaenius can provide you with.
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