405_April_24

FEBRUARY 1974 marked the 50th anniversary of the publication of Peter Benchley’s novel “Jaws”. Underwater filming of scenes for the movie based on the book occurred in South Australia that same month. The filming took place at Dangerous Reef near Port Lincoln. Ron and Valerie

wreck of the South Australian* in Encounter Bay at Yilki. The establishment of seagrass communities around the wreck is expected to help to preserve and protect the wreck from both storm surges and exposure to destructive marine organisms. Payment for launching at local boat ramps is now starting to involve the use of mobile phone apps. This technology doesn’t suit everyone though. Onkaparinga Council reintroduced a cash payment system to cater for these people. Physical permits can be purchased from council’s Noarlunga office during business hours. One species of shark that I won’t find in my reference books is the critically endangered speartooth shark, Glyphis glyphis *. It is a rare species of river shark that inhabits coastal marine waters and the tidal reaches of large tropical rivers in northern Australia and New Guinea (NOT quite “Southern Waters” material).

Valerie Taylor and myself in 2018

Taylor and Rodney Fox all worked with the US film team. All other filming was done in the US, much of it at Martha’s Vineyard. The movie came out in 1975. Sadly, Peter Benchley died in February 2006. The Underwater Explorers Club of South Australia held a picnic on 3rd March to celebrate the club’s forthcoming 70th anniversary in June. The picnic was attended by 30-40 past & present members. They got to indulge in a UEC-themed cake washed down with some bubbly. There may still be a get-together later to share ‘yarns’.

Researchers from Charles Darwin University (CDU) and First Nations Yugul Mangi Rangers discovered the speartooth shark in a recent survey in Roper River in Australia’s ‘Top End’. Dr Peter Kyne of the CDU said that their survey results show that the speartooth shark “ occurs in a limited stretch of the downstream Roper River ”. Its discovery in the river is important for the survival of the species. “ The population could decline rapidly in the face of threats, so we need to determine how these environmental changes impact them and come up with ways of managing them. If we don’t, then this population … could be lost forever ,” Dr Kyne said. According to MS Copilot, “ Despite being a member of the river shark genus, it is also found in near-shore marine waters, favouring highly turbid environments over a wide range of salinities. The speartooth shark is characterized by a short and broad snout, tiny eyes, a relatively large second dorsal fin, and a black blotch beneath each pectoral fin near the tip. Adults grow to about 2.6m long. Preying on demersal bony fishes and crustaceans, it is adapted for hunting in near-complete darkness. Reproduction is viviparous, with females forming a placental connection to their young, though details are unknown. Due Glyphis glyphis is also a tautonym, a scientific name in which the genus and species names are identical. Source: https://www.adelaidenow.com.au/news/rare-and-endangered-shark-found populating-the-roper-river/news-story/2a1390e31617fbee885685cd4f68b9a2

Picnic held for the 70th anniversary of the UECSA. Image credit David Muirhead.

Marine Life Society of SA anniversaries also fall each June. 2024 marks the Society’s 48th anniversary. The Society is presently lobbying for the protection of eagle rays at Seacliff. As the current President for the Marine Life Society of South Australia (at the time of writing), I occasionally feel guilty about my obsession with shipwrecks. I do feel better about it, however, when the Acting Environment Minister says , “ From a tourism perspective, (shipwrecks) can offer a one-of-a-kind experience to divers and snorkelers (sic) to explore underwater. An assortment of marine life can often be found in and around shipwrecks .” The Minister may have read Bill Jeffery’s paper titled “ Realising the Cultural Tourism Potential of South Australian Shipwrecks” which stated, “ Shipwrecks attract fish ….. they contain a wide variety of marine life .” MLSSA mirrored these thoughts a little in its Port Adelaide Anchor Trail guide, stating “ Anchors lost at sea quickly become habitat as they are colonised by a range of plants and invertebrates. These can include algae, sponges, ascidians, molluscs, worms, echinoderms and crustaceans. These combined

to its small population, restricted range, and stringent habitat requirements, this species is highly susceptible to threats and has been listed as vulnerable by the International Union for Conservation of Nature (IUCN) .”

maritime and natural heritage values make anchors points of interest for divers, historians and naturalists alike.” OzFish Unlimited’s Seeds for Snapper program is working with the Department for Environment and Water and Flinders University to deploy some Posidonia seagrass seed ‘sandbags’ around the 1837

Source: www.adelaidenow.com.au/news/rare-and endangered- shark-found-populating-the-roper-river /news-story/2a1390e31617fbee 885685cd4f68b9a2

Anchor from the South Australian The South Australian was, coincidentally, SA’s first ‘official’ shipwreck.

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DIVE LOG Australasia #405 - April ‘24