{"id":36203,"date":"2017-04-20T18:11:19","date_gmt":"2017-04-20T08:11:19","guid":{"rendered":"http:\/\/nofibs.com.au\/?p=36203"},"modified":"2019-04-16T13:31:08","modified_gmt":"2019-04-16T03:31:08","slug":"shark-attack-when-auspol-meets-marine-apex-predator-the-great-white-shark-takvera","status":"publish","type":"post","link":"https:\/\/archive.nofibs.com.au\/shark-attack-when-auspol-meets-marine-apex-predator-the-great-white-shark-takvera\/","title":{"rendered":"Shark attack: When #auspol meets marine apex predator the great white shark – @takvera"},"content":{"rendered":"
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Photo by Terry Goss via Wikimedia Commons: Great white shark<\/a><\/p><\/div>\n

\nJohn Englart published this article on The Great White shark, climate change and ocean carbon cycles<\/a> on his climate blog.<\/em>\n<\/p>\n

\nThe latest media ‘hysteria’ about shark attack arises from a tragic fatal bite incident when WA teenager Laeticia Brouwer was mauled by a shark at the popular surf break – Kelp Beds – near Esperance (south coast of Western Australia) just before 4pm on Easter Monday (2017).<\/p>\n

\nThe paramedic who was first on the scene said the teenager suffered tremendous blood loss and couldn\u2019t be saved despite quickly receiving first aid.<\/p>\n

\nWhile sharks are relatively common in coastal waters, attacks are exceptional given the overwhelming presence and numbers of people in the surf zone. You are more likely to be killed in a road accident, riding a horse or a vending machine, than by a shark.<\/p>\n

\nFederal Environment Minister Josh Frydenberg says WA isn\u2019t doing enough to protect people from sharks<\/a> urging shark culls and drum lines, according to the West Australian<\/i>. “In light of the recent shark attack, the Commonwealth would welcome any proposal to protect human life first and foremost,\u201d he said. \u201cThis could include the newest drum-line technology, shark exclusion nets, culling or other measures which WA sees fit.\u201d\n<\/p>\n

\nWA Fisheries Minister Dave Kelly has ruled out the idea of a shark cull<\/a> in response, according to the ABC<\/i>. “We’re not going down the path of a cull because there’s no evidence that it actually makes our beaches safer,” he said, “…no evidence that that actually reduces the likelihood of future attacks,” Kelly said.\n<\/p>\n

Like on climate change, we are seeing the issue of shark conservation or culling being politicised for short term ideological battle rather than long term concern for public safety, public education and options for shark incident mitigation.<\/p>\n

\nOur Federal Environment and Climate Change Minister Josh Frydenberg should know better. The environment and climate change is his portfolio after all. The oceans are the domain of sharks and they have an important role to play as apex predators as part of the ocean carbon cycle.<\/p>\n

\nWhen we swim in the oceans we need to be mindful of the risks involved, including utilising the latest in public shark warning and repellent devices.<\/p>\n

\nMindless culling of sharks will not actually reduce the risk of shark attack without doing great harm to the ocean ecosystem trophic structure. It is as apex ocean predators that sharks do us the greatest service in maintaining the ocean carbon cycle and help keep carbon sequestered in coastal sea areas (Blue Carbon) to help us mitigate climate change.<\/p>\n

\nClimate change and warming sea surface temperatures (SSTs) are one factor which might be affecting shark behaviour and shark bite incidents. I examined this issue in an article that looked at Sea surface temperatures unusually warm around Australia in 2013<\/a>. I updated this article on 9 January 2014 with a section on Sharks and warming waters<\/a>. The evidence is still very poor in linking frequency or number of shark attacks to climate change factors. But we do know climate change is affecting ocean systems a number of ways.<\/p>\n

\n“Climate change is affecting the open ocean through an interaction of warming, stratification, deoxygenation and acidification, with subsequent effects on a wide range of top predators.” says a February 2015 article in Deep Sea Research II: Topical Studies in Oceanography<\/i>. (Hobday et al 2015)\n<\/p><\/blockquote>\n

\nSydney Morning Herald<\/i> environment journalist Peter Hannam has written a major feature article over the 2017 summer: Shark alert<\/a>, in which he argues that many of the shark bite incidents on the east coast of Australia appear to be just taste testing with an initial bite incident that often is not followed through with any subsequent attack. The fatal nature of some of the incidents mostly results from the extent of blood loss involved rather than damage to major organs.<\/p>\n

\nSenior CSIRO scientist and shark researcher Barry Bruce was quoted in the article that he is doubtful the evidence is there to support any links between shark bite incidents and changes in water temperature. \u201cThey have been some upwelling events in the past when there\u2019ve been no shark attacks,\u201d he says.<\/p>\n

\nHannam followed up his first article on the human\/shark conflict with an article on the race to find a reliable shark repellent<\/a>. In the third article in the series, by Emma Young, the failed Western Australian hazard reduction policy<\/a> of baited drum lines and culling is looked at in depth, as well as a vox pop of beach goers on the issue.\n<\/p>\n

\nOther research on pelagic shark populations from the North Atlantic ocean makes a general link that shark hotspots correlate well with Sea Surface Temperature gradients and front frequency, according to marine ecologist and shark researcher David Sims. <\/p>\n

\n“Movement modeling showed sharks preferred habitats characterized by strong sea surface-temperature gradients (fronts) over other available habitats.” says the 2016 study published in PNAS (abstract<\/a>).<\/p>\n

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\nOceanic #sharks<\/a> orienting according to gradients in #SST<\/a> and #chla<\/a> – preference for frontal zones @TheSimsLab<\/a> talks @IMASUTAS<\/a><\/p>\n

— Kirsty L. Nash (@NasherK) April 12, 2017<\/a><\/p><\/blockquote>\n