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MARINE Life June July 2015 ISSUE 37 1 Features and Creatures Our Goal To educate, inform, have fun and share our When humans declare war on fish 3 enjoyment of the marine world with likeminded Fish Le ss, Earn More /Tropics at risk 4 people. Herring Stocks Down 5 Marine Heat Wave two years later 6 The Crew Abrohlos Clean Up/ Artificial shellfish reef in Vic 7 Michael Jacques, Editor Shark Cage Diving Expands ` 8 NT Advisor – Grant Treloar SA Advisor – Peter Day New SA Shellfish reef/ Cuttlefish recovery signs 9 WA Advisor – Mike Lee Reducing Turtle Deaths/ GBR Fishing Impacts 10 Disclaimer: The views expressed in this publication are not necessarily the views of the editorial staff or associates of this Developing the Tiwi Islands 11 publication. We make no promise that any of this will make Adele Penguins 12 sense. Jurassic Survivors 13 Cover photo, Point Lonsdale Lighthouse, Port Phillip Bay, Victoria by Andrew Newton Urchins 14 Tamar River Feature 18 Iron Ships 24 Loch Line Wrecks, Loch Leven, Loch Ard, Loch Vennachar 25 \ Pt Danger Gannets and their guard dogs 30 We are now part of the wonderful world of Facebook! Check us out, Little penguins/ State of the Derwent 31 stalk our updates, and ‘like’ our Snares penguin released/ marvellous gulls 32 page to fuel our insatiable egos. Contact us: [email protected] Go to Page 26 if you want to save our fast disappearing shore birds 2 When Humans Declare War on Fish the industrial fishing debate agrees on one thing, that our citizens should read more and find more out about the science. Hopefully this Review by Mike Jacques article will get you thinking and reading, whether you love it or hate it. John and Jane Elek have forwarded a link to a New York Times Before you all write in and complain, yes we do manage our fisheries article reflecting on industrial fishing in the aftermath of WWII. better than that in Australia, which wouldn’t be hard as the record up It doesn’t pull any punches and here is an appetiser. north is pretty appalling and remains so. The journalists have typified post-war fishing in very strong terms as a For copyright reasons, I can only review this article, but you can see the “campaign of violence” against another species. World War II brought a whole article on, leap in human ingenuity. Ships become larger, faster and more http://www.nytimes.com/2015/05/10/opinion/sunday/when-humans- numerous with increased fishing power. Sonar, developed for hunting declared-war-on- submarines, could now hunt fish, “...the modern fishing vessel became fish.html?emc=edit_ae_20150509&nl=todaysheadlines&nlid=30774450 a kind of war machine”. Some pretty strong metaphors there. This point is taken further and even “Japanese fighter pilots adept at My Holiday Snaps spotting subsurface Allied submarines were later retrained to look for whales”. It is a great image, but I’m not sure it would be brought out in I will however a statistical review of the life histories of spotter pilots. shamelessly use this article as a prop to sneak With a bit more clarity they point out that fishing was transformed from in some holiday photos. a local endeavour into a global one. Industrial fishing is,”…maybe the On a recent trip to Elba in first globalized economic enterprise”. Apparently, postwar super Italy, I dived in some trawlers scooped up everything in their path, “a sort of scorched-earth lovely clear and warm approach”. Global reported catch rose from 15 million metric tons at water, but on reefs war’s end to 85 million metric tons today. “To be sure, the postwar devoid of fish of any size assault on fish mostly sprang from an honorable intention to feed a and covered in algae. A growing human population that boomed in a prosperous postwar world”. disaster for fish, fishing Recent times are referred to differently and more positively, not as a and recreation. After the success story of better management (as we often hear in Australia), but dive I asked where all the as a result of “...signs of exhaustion and failure in global fisheries”. fish had gone. Apparently you have to go to Marine protected areas, “…an environmental version of a demilitarized Portofino to see fish. Let zone” now cover some 3.5 percent of the ocean. Better regulation has me guess, it’s a marine been attempted. “Collateral damage” to sharks, turtles, whales and sea reserve? Despite being birds is increasingly becoming unacceptable. overfished for a thousand The writers want “...a broader Marshall Plan, which would further years just like Elba, restrain our destructive tendencies and technological powers...”. apparently Porto has reasonable sized fish and I suspect the even the writers covertly recognise that this article is a less algae after only 16 polemic, intended to get past the editor on a day when the issue was years of being protected. only running VE Day memorials. It is designed to jolt us into thinking about our score card after 70 years of peace. At the least, everyone in 3 Fish less, Earn More Tropical Oceans Most at Threat Well enforced fishing areas can boost the incomes of fishers by up to 50 per cent more than in unregulated ‘anything‐goes’ An international team of areas. scientists has used the 23- Source, “Accounting for enforcement costs in the spatial allocation of marine zones” by million-year fossil record to Katrina Davis, ARC Centre of Excellence for Environmental Decisions (CEED) calculate which marine animals and ecosystems are most at Ms Davis explains that uncontrolled industrial and consumer demands risk of extinction today. are driving over‐fishing in the world’s oceans, threatening the survival of reefs in places such as the Coral Triangle. To manage this threat, Source: ARC Centre of Excellence for Coral governments are setting up reserves and regulating fishing in certain Reef Studies at the University of locations – all of which allow fish stocks and fisheries to recover. Queensland. However, the effectiveness of these systems depends on support from coastal fishing communities. Around one billion people rely on fish for protein, and tens of millions fish for their income. The researchers found those animals and ecosystems most threatened The researchers used Chile – one of the world’s top 10 exporters of fish are predominantly in the tropics. The researchers found that the and fishery products – as a case study to identify how fishing incomes predictors of extinction vulnerability, geographic range size and the type can be protected while anti‐poaching rules are enforced. This includes of organism, have remained consistent over the past 23 million years. limiting the catch, surveying the population of key fish species each They were able to use fossil records to assess the baseline extinction year, and paying for all management costs used to monitor and stop risk for marine animals, including sharks, whales and dolphins, as well poachers. The study shows that fishers earned more in enforced zones as small sedentary organisms such as snails, clams and corals. They than they did in open‐access areas. then mapped the regions where those species with a high intrinsic risk are most affected today by human impact and climate change. The increase in revenue stems directly from the increase in fish numbers which occurs when poaching is eliminated. By leaving enough “These regions are disproportionately in the tropics, raising the fish in the ocean to reproduce the can now reproduce at the maximum possibility that these ecosystems may be particularly vulnerable to rate. future extinctions.” On the other hand, fishers operating in open‐access areas are much more likely to exceed safe catch limits – and drive down fish abundance. “Marine species are under threat from human impact, but knowledge of “Even if an individual fisher wishes to leave some fish in the sea, he their vulnerabilities is limited,” says study co-author, Professor John can’t guarantee that his neighbour will do the same,” Ms Davis says. “So Pandolfi. The scientists say that identifying the regions and species at everyone takes as much as they can from the common resource, and greatest risk means conservation efforts can be better targeted. this ends up depleting the fish stock. As a result, fishers spend more time fishing for fewer fish...” “… there is a lot more work that needs to be done to understand the The researchers interviewed fishers and divers in the area, who were causes underlying these patterns and their policy implications,” says aware of the benefits of fishing sustainably, Ms Davis adds. “They are Asst. Professor, Seth Finnegan. aware they spend less time fishing and have a lower risk of running out of catch compared to open‐access areas.” 4 National News recreational catches Herring science from South Australia and WA’s south coast add up to about 75 per cent of the annual catch – so high numbers of herring are removed before having a chance to spawn. In addition, fishers on WA’s west coast are targeting the remaining fish that have made it into the adult breeding stock. West coast fishers usually target herring during autumn when they aggregate (gather) before spawning. For reasons that are not clear, breeding females are particularly vulnerable Research has revealed that a combination of environmental factors and to being caught by line at this time. The west coast recreational catch fishing pressure has diminished the Australian herring (Arripis during the spawning season is dominated by females – roughly 80 per georgianus) stock in southern Australian waters. cent of the total catch. Environmental factors including a steady rise in ocean temperatures and Fishers may catch many herring in one particular area, which may give unusual flow patterns in the Leeuwin Current are thought to have the impression of a thriving stock.