DIVE LOG Australasia

OCTOBER 2024 | No 408 digi tal

AUSTRALASIA

www.divelog.net.au

Cave Diving in Indonesia ANITA FUTTERER Freediving from Surface to depth VADIM BELAKHOV

Padang Bai, Indonesia KEN HOPPEN Cathie Cummins SPOTLIGHT

Frolicking with Sharks & Fishes in Palau NIGEL MARSH

Shark Reproductive Techniques MIKE SCOTLAND

Night Diving on Wakatobi’s House Reef MIKE SCOTLAND

PAPUA NEW GUINEA

Dive the majestic reefs of Kimbe Bay and the Bismarck Sea with us. Choose from a resort stay at WALINDI RESORT or a trip on one of the two liveaboards, MV FEBRINA and MV OCEANIA .... why not combine land based and liveaboard diving.

Contact our friendly reservations staff for a package to suit you. reservations@walindifebrina.com reservations@mvoceania.com

Image © Kyu Furumi

MV FeBrina has been operating from Walindi Resort since 1991. Image © David Doubilet Bismarck Sea, inc. New Britain & Kavieng

Walindi Plantation Resort celebrates 40 years of operation.

Our newest dive liveaboard operating out of Walindi Resort since 2019. Diving Bismarck Sea and Milne Bay

Diving Kimbe Bay Reefs

Image © Grant Thomas

Image © Grant Thomas

A boutique, traditional style live-aboard catering for 10-12 guests in 7 cabins, including large and small singles.

Tropical bungalows in rainforest gardens with waterfront and garden views.

MV Oceania is a 27 metre catamaran catering for up to

16 divers in 8 cabins. Modern comfort with two guest deck levels.

Image © Darek Sepiolo

Image © Franco Banfi

Image © Scott Johnson

WWW.WALINDIRESORT.COM

WWW.MVOCEANIA.COM | WWW.MVFEBRINA.COM

ADVANCED TECHNOLOGY. CLASSIC STYLE.

GALILEO 3 DIVE COMPUTER Sharp Color Display for Easy Readability

NEW

Cast your mind back to when you were five years old. Your imagination knew all about hitching a ride on giant seashells. Sea Stars recite Fairy Tales of great wonder. You dreamed that ice creams would appear in your hand the moment that you wished for them and you had the power to change rocks into chocolate. Somehow, the reality of adulthood erased the magic. You saw humans were chopping down all the trees; stripping the fish and whales from the sea and dumping rubbish into the water. Mother Nature was direly in need of protection as the sadness grew in the world. Some of her precious spaces were turned into ‘The Nothing’, a zone of desolation and emptiness, which spread across continents and oceans. Fortunately, there are people doing something to remedy the problem. The solution is to rebuild the Garden of Eden. Our home, the Blue Planet is a rare gem in the vast emptiness of space. It is not ours to destroy for profit. The sooner we realise how precious it is, the sooner we can repair it. The days of seeing a whale and killing it on sight should be well and truly over. It is a crime against Mother Nature. All life is sacred. In 2024, we witness the gradual return of whales. Whaling was stopped in 1978 not because of any love of whales or environmental concerns. The whale population was down to 1% to 2 % and it was not worthwhile financially. Over the next thirty years, whale numbers were scarce. They are steadily recovering from the brink of extinction. The mass murder of whales in the previous centuries was an inter-generational crime! We all were deprived of wonderful marine encounters with these gentle giants. In the words of a famous teacher, I say to myself “Forgive them for they know not what they do.” Most of us know better now! Luckily, these days we can visit the ocean and listen for the whales. You will witness one of the great symphonies of the planet. The ocean is filled with whale song in winter. The music is loud and clear and full of joy; a song of love and romance that is simply brilliant to experience. We stand on the precipice of time, facing the future. We can set our minds to heal the planet in this moment. It is so easy! Go and plant a tree. If you own a house, plant lots of trees, grow some vegies. The birds and the bees will come. Life will proliferate. ‘The Nothing’ will vanish. My quarter acre block is a rainforest with hundreds of trees. We have so many wonderful visitors. Well fed Kookaburras and Magpies sing to us every day; a female Bower Bird visits often. We even get Tawny Frogmouth at Christmas. In short, it is alive. What will it take to fix our planet? OUR COVER PHOTO OUR FRONT COVER photo by Cathie Cummins shows a friendly Potato Cod. She captured this image using her Nikon Z50 on a recent trip to the Great Barrier Reef.

One of the first steps is to revegetate the Earth. We need to plant a trillion plants a year across the globe. Wildlife will find it and their numbers will rebound from the brink of extinction. We need to stop the over exploitation of the seas. I am amazed that Scientists tell us again and again that the world fisheries are on the verge of total collapse yet people spend their entire life trying to catch and kill those last few creatures. We need to protect the oceans right now. The ‘big solution’ is right there before our eyes. The ocean has always been exploited for food and money. It has been vandalized and treated like an never ending resource. To save the ocean, we need to put a dollar value on an ocean that is pristine, filled with life. It is not a worthless space to be exploited. It is a valuable aquatic real estate. How do we save the Great Barrier Reef? The answer, in part, is to use the positive side of economics. Revalue the reef from a worthless patch of nothing ‘real estate’ to a place of value where fish can breed, food can be produced and people can play. In short, see it as a resource to be protected. Mankind’s love affair with the almighty dollar has been the obstacle; now it is the way forward. It will give people the power to see a hectare of ocean as having worth. Instead of overfishing and destroying complete ecosystems, let them recover. They will return to be productive spaces that provide food, entertainment, pleasure and, of course, financial rewards. The result will be good for all. The Ocean Biome has its own feedback systems to restore the balance and to correct the damaged ecosystems. Few people talk about these important cycles in Nature but that are in operation all of the time. After all, every ecosystem I have ever visited in my life is seriously out of balance. These feedback mechanisms are always hard at work trying to fix the issue. Once the food producing vegetation is removed, the food webs are out of balance and top order predators starve and die. If allowed to recover, these ecosystems can rebuild in just a few years. It is called Nature and its powers of regeneration are legendary. One vivid example is the effect of the ruthless extermination of whales off Eastern Australia until 1978. Their natural predator, the Orcas had lost their main food source. I often wonder what happened to Australian Orcas. Did they starve to death or maybe migrate to New Zealand or Tonga or find somewhere where they could survive? Did they die of starvation? These days, as whale numbers increase, we are seeing the return of Orcas. Dive Log Australasia is a tool for education and a voice for Mother Nature. We like to highlight issues of concern and use education and photography as a tool to help to do out bit to protect the ocean. This issue is another blockbuster production filled with great travel articles, educational articles on Nudibranchs, sharks and Turtles. As usual, our excellent team of diving photojournalists and Vikki create a world-class production for your reading pleasure. Read on and enjoy our spring issue.

Mike and Vikki

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CONTENTS

digital

N o. 408 NEXT ISSUE DEADLINE : Issue 409 DEC 2024 Advert bookings 1st Nov Artwork due 15th Nov Editorial material : 7th Nov OCTOBER 2024 EDITOR Mike Scotland | mike@divelog.net.au Production Editor/Designer Vikki Ryan | divelog@divelog.net.au PUBLISHER Mike Scotland | mike@divelog.net.au ADVERTISING Mike Scotland | mike@divelog.net.au MENTOR Barry Andrewartha | barryandrewartha@outlook.com Tel: + 61 0415158168 mike@divelog.net.au www.divelog.net.au Editorial and photographic contribution guidelines: divelog@divelog.net.au The views expressed by contributors are not necessarily those of the publishers or its editors. REPRODUCTION OF CONTENTS No part of the contents of this publication may be reproduced without the prior written consent of the publisher. All images are copyrighted by the authors and photographers.

Features

016 Go Dive Show latest news 023 Turtle Detective - Mike Scotland

034 Explore Cave Diving Indonesia - Anita Futterer 040 Freediving Surface to Depth - Vadim Belakhov 044 Mystery of Turtles - John Magee 048 Frolicking with Sharks & Fishes of Palau- Nigel Marsh 055 Octopus Underwater Wonders by Sharee Marris - Review 058 DIVE Talk Show News 070 SPOTLIGHT Photographer - Cherie Cummins 074 Night Diving House Reef Wakatobi - Mke Scotland 088 MB Fish ID Shark Reproduction Techniques- M Scotland 100 Nautilus S/C Cairns Underwater Photography winners

Regulars

68 - In Deep - Simon Pridmore 72 - Historical Diving Society - Des Williams 82 - Sthrn Waters & Wrecks - Steve Reynolds 84 - WOW - - Dr Sally Gregory 87 - Lynne Tuck’s Red Indian hunt 108 - Your Shot 110 - Boat Directory

07 - Mike Ball Expeditions Spoilsport update 10 - DAN News 12 - PNG Resort Listings 14 - Diving Medicine - Simon Mitchell 20 - NudiNotes - David Mullins 33 - Go Dive Show Speaker Mike Scotland

56 - Paul Watson Foundation News 65 - Counter Strike -David Strike 66 - SDFSA - Heather Creech 67 - Dive 2000 - Kevin Deacon

112- Parting Shot 114 - ADEX Japan

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Great Barrier Reef on the October

View from the Bridge Trevor Jackson - Spoilsport Skipper www.mikeball.com/blog

PHOTOS FROM JULY/AUGUST

The Ocean Calendar

“What are the tides Daddy”? It’s an easy enough question to answer to an adult… but when your three-year-old son asks from the back seat of the car, surprisingly, things get tricky. No point trying to explain gravity and orbital mechanics in this instance…so I had to think on my feet. “The tides are like the ocean breathing darling, a big breath in and all the water flows in toward the land, then breathe out and it rushes back out to sea” I pondered my cleverness for a second, but my self-congratulatory moment was short-lived…the six-year-old chimed in with a doozie. “Dad how do Minkes know when to come back each year?”. “Well that’s easy honey, they just check out the ocean calendar”…“The Ocean Calendar?!! What’s that?” So now I was in a pickle, my bluff had been called and if I wasn’t going to be branded a fake by the kids…a decent answer was required! “Well, all the Minkes have to do is watch what’s going on around them and they can tell exactly what time of year it is…The Ocean Calendar is deadly accurate.” Now…my kids aren’t stupid, they smelt a giant wharf rat, so they pressed me…“Give us some examples!”. I paused for a second and then realized, this might just be easier than I thought… “Well, it goes like this…In January, the seas are like glass. In March, the baby turtles hatch. In May, the humpbacks remind the Minkes it’s time to come to Queensland, so in June, they do. Hot on their heels, the Hammerhead Sharks arrive at Osprey, and that reminds the Marlin it’s nearly time for them to show up in September. Then in November the Coral Spawns so that tells the turtles it’s time to go to Raine island just in time to lay their eggs so the babies can hatch in March…you see it’s like mums yearly planner”. A quick glance in the rear vision mirror told me I had successfully bluffed my way through this particular inquisition, but when I thought about it later…I realized, the ocean calendar kind of does exist. If I were to look out the wheelhouse windows and see a Minke, I would know it was mid winter…and now that November is upon us…well, Raine Island here we come, the turtles await.

1st. Jane Kempler

2nd. Marissa Lofflad

3rd. Pavlos Evangelidis

Coral Sea & Great Barrier Reef! The Best Diving on the Dive with giant potato cod, explore deep walls, witness shark action at Osprey Reef.

New Special Expeditions! Check out our website for details.

Ribbon Reefs Suited to both Divers and Snorkelers.

www.mikeball.com T: +61 7 4053 0500 E: resv@mikeball.com #spoilsportlive #mikeballdive

September many Lined Sweetlip aggregation at the Cod Hole.

August neap tide at Pixie Gardens.

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“ The reef systems here are some of the most pristine I have seen anywhere in my dive travels around the globe, and Wakatobi resort and liveaboard are second to none. The diversity of species here is brilliant if you love photography.” ~ Simon Bowen

Know Your Neuro

A s the waves crashed over the reef ahead, the small dive boat anchored nearby careened at their mercy — despite being anchored in a relatively sheltered spot. No one’s ladder exits were pretty that day, but the third diver in the group really struggled to get back onboard. Once the divemaster and captain assisted him onto the deck and helped him out of his gear, he was breathing hard and fiercely gripping the bench on which he sat. In an attempt to comfort the diver, the divemaster asked him if he needed some water. He clearly and coherently replied, “Yes, thanks.” When the divemaster returned with his water, the man seemed suddenly unsure why the divemaster was giving him water and when he began to try and speak he was slurring his words.

At first the divemaster was stumped by the diver’s condition so he looped in the boat captain to try and gain more insight. “Could this guy have DCS after a 30-minute dive to 7.5 metres? We came up so slowly …. He seems disoriented. AGE maybe?” “Presenting with symptoms immediately after a dive doesn’t necessarily mean this guy has a diving injury. Let’s do a neuro.” After conducting a quick neurological exam, the

captain discovered that the diver was unable to lift his right arm and has persistent slurred speech. She called emergency services from the boat and arranged for an ambulance to meet them at the dock because she suspected he might be having a stroke. She noted

the time of symptom onset and made haste back toward shore. Fifteen minutes later, the diver was transported by ambulance to the local emergency room for treatment. The attentiveness of the crew, quick action on part of the boat captain and their proximity to shore had saved this diver’s life, and all they had to do was act FAST. Face, Arms, Speech, Time – FAST is the mnemonic you use to recall how to properly conduct a neurological exam. Check for facial droop and inability to move or raise an arm, determine slurred, mumbled or nonsensical speech, and

remember to note the time symptoms began. If you detect any of these symptoms, call emergency medical services immediately. Using FAST to begin your neurological examination is an effective way to determine if a neurological injury is present — whether from a stroke, trauma or a diving injury. Quick and correct response to a neurological injury can make a life-or-death difference; the faster a victim of AGE or stroke reaches advanced medical care, the greater their likelihood of avoiding a life-altering disability or further injury. Diving Health and Safety Resources The DAN World website contains an extensive range of health & medicine as well as safety & prevention resources and reference materials that are freely available to all divers, as part of DAN’s mission to enhance diving safety.

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PACIFIC OCEAN

• Diving is possible all year round with the optimal season typically from mid April to mid June, and mid September to mid December.

KAVIENG

NEW IRELAND

MANUS ISLAND

VANIMO

BISMARCK SEA

• Water temperature from 26º along the edge of the Coral Sea and up to 31ºC in the Bismarck Sea. • Visibility ranges from 50 to 150 ft • PNG has a hyperbaric chamber maintained to international standards • The use of permanent environmental moorings ensures minimal anchor damage to reefs. • Weekly flights to Port Moresby from Singapore, Hong Kong, Tokyo, Manila, Kuala Lumpur, Honiara, Nadi. Daily flights from Cairns, Brisbane, Sydney. • For the best dive and air package pre-book your complete tour with a recognised PNG dive travel specialist.

RABAUL

WEWAK

KIMBE BAY NEW BRITAIN

MADANG

TARI

HOSKINS

MT HAGEN

GOROKA

PAPUA NEW GUINEA

BOUGAINVILLE ISLAND

LAE

SOLOMON SEA

GULF OF PAPUA

TUFI

PORT MORESBY

MILNE BAY

ALOTAU

www.walindiresort.com

www.lissenung.com “Instruction, gear rental, 8 rooms (6 with ensuite, 2 with semi ensuite), free WiFi, full resort facilities. A visit at Lissenung Island Resort is truly exclusive! info@lissenung.com

Instruction, gear rental, Nitrox, 12 bungalows, 8 plantation house rooms, all ensuites, internet, pool, full resort facilities, English. Voted the 'Best diving from a resort anywhere in the world', Walindi comprises fern-draped bungalows set in tropical rainforest gardens on the shores of Kimbe Bay.

resort@walindifebrina.com

MV OCEANIA LIVEABOARD www.mvoceania.com

www.mvfebrina.com

Gear Rental, Nitrox, 10-12 passengers, English MV FeBrina cruises from Walindi Resort, diving Kimbe Bay, Witu Islands, Fathers Reefs, Rabaul and New Hanover. febrina@walindifebrina.com

Gear Rental, Nitrox, 16 passengers, English

MV Oceania is the most recent liveaboard addition to Kimbe Bay. A 27 metre catamaran, Oceania began operation in 2019 with itineraries including Kimbe Bay, Witu Islands and Fathers Reefs as well as further afield at select times of year. reservations@mvoceania.com

Image credit David Doubilet

LOLOATA ISLAND RESORT www.loloataislandresort.com

NIUGINI DIVE ADVENTURES www.niuginidiveadventures.com

The only dive company established within ‘beautiful Madang’; the PADI certified facility, NDA is one of the most experienced dive operators in Papua New Guinea. NDA offers resort courses taught by our team of multi-lingual, PADI certified instructors and dive masters. The crystal clear waters surrounding Madang offer some of the world’s best diving experiences for divers to discover. Most

Luxury Island Resort with 68 rooms/villas, two restaurants and bar, a swimming pool, recreational beach, fully equipped dive shop, spa and conference centre. Importantly, it sits on the edge of the Papuan Barrier Reef and 29 dive sites around the island where experienced divers can explore its reefs, spectacular sea life and shipwrecks. There are also excellent snorkelling sites. Loloata’s PADI-certified dive and activities centre is opened now, so learning to dive is also now an option. t: +675 7108 8000 / 7914 3966 e : reservations@loloata.com

dive sites are only 5-10mins away! Underwater peaks climbing from 600m to 4m and sheltered lagoons where old wrecks, dating back to World War II, are waiting to be explored...Contact info: nda@madangresort.com

KARAWARI LODGE www.pngtours.com

TUFI RESORT www.tufiresort.com

AMBUA LODGE www.pngtours.com Fly across mainland Papua New Guinea to remote and magical Karawari Lodge. The lodge overlooks the Karawari River whose waters flow towards the Sepik River. Stilted villages line the edges of the waterways. Dugout canoes glide by. Lodge guides introduce guests to the complex and mysterious tribal culture. Conversations with villagers are fascinating. Photo opportunities abound. Explore mainland Papua New Guinea based from eco-friendly Ambua Lodge. The lodge is nestled in the highlands, overlooking the magnificent Tari Valley, home of the famous Huli Wigmen. Visit their traditional lands and learn about their fascinating culture. Follow walking trails through mid-montane forest, over traditional vine bridges and along clear mountain streams to secluded waterfalls. Watch for Birds of Paradise.

Discover Tufi in a boutique resort with 180 degree panoramic views over the sea and the only fjords in PNG. Experience diving in a secluded paradise with abundant sea life, coral reefs and wrecks. The warm crystal clear waters of Tufi are a divers paradise. Gear rental, water activities, village stays, cultural and land tours. 24 air conditioned ensuite guest rooms, pool, full resort facilities. reservations@tufiresort.com

service@pngtours.com

RONDON RIDGE www.pngtours.com

In the mountains of mainland Papua New Guinea, above the town of Mount Hagen, sits Rondon Ridge. Rising mists enhance the lodge’s panoramic views of the historic valley below. Orchids thrive here. Hours of walking trails offer opportunities to spot exotic birds, including Birds of Paradise. Lodge

guides share the history and traditions of the Melpa people. Rondon Ridge is conveniently accessible on scheduled flights between Port Moresby and Mount Hagen. service@pngtours.com

service@pngtours.com

TAWALI RESORT www.tawali.com

Instruction, gear rental, Nitrox, 22 ensuite rooms, Broadband, full resort facilities.Where it all started, discover the dive sites that place PNG into the world class map of scuba diving. Situated on a limestone bluff backed by densely rain

forested hills overlooking the clear and protected water of Milne Bay, Tawali offers travellers a unique location to dive, relax and enjoy the unspoiled wonders of this magnificent part of the world. reservations@tawali.com

ADVANCED KNOWLEDGE SERIES: PNEUMOTHORAX

Diving Medicine

Why Can’t I Dive? Professor Simon Mitchell, University of Auckland A s a diving physician, one of the commonest questions I hear is “why can’t I dive”; commonly put in relation to a medical condition. The answer is often a nuanced evaluation of risk versus benefit. There are very few medical conditions that represent such a significant risk that diving should probably never be contemplated (and I will discuss one of these below). The approach to most conditions involves carefully assessing the potential risk implied by a particular medical condition, how that risk can be minimised, and whether the potential risks outweigh the benefit of diving. These are often quite complex evaluations that require the doctor to have knowledge of both medicine and diving, and they should involve the diving candidate as an informed evaluator of risk versus benefit.

There are hundreds of medical conditions and potential severities of those conditions that a diving candidate might “bring” to a diving medical consultation, and it is impossible to have a set of established rules that cover all situations. Instead, it is common for diving physicians to apply an analytical three question paradigm in evaluating the potential interaction of any medical condition and diving. First, we ask ourselves “will this condition be made worse by diving”? Second, we ask “will this condition make a diving disorder more likely”? Finally, we ask “could this condition impair physical performance or consciousness in the water”? If the answer to any of these questions is yes, then careful consideration of the advisability of diving must be undertaken. Medical conditions are common, and the above approach to analysing their impact in diving often identifies potential risk, but this does not necessarily mean that the candidate cannot dive. Indeed, if the associated risk seems low or can be managed, then it is typically a matter of explaining that risk to the candidate, describing how the risk might be minimised, and allowing the candidate to make an informed risk acceptance decision to dive (or not). There are, however, several medical conditions that represent what one might describe as “absolute contraindications” to diving. That is to say, if you have them, then diving is generally considered too risky to contemplate. There are other medical contraindications of course, but many of them can be treated and the risk they represent in diving

reduced to a point where diving may be feasible. Unfortunately, this is not so true for several absolute contraindications. I am often asked about them, and so I thought it would be useful to briefly address them in these articles. In this issue I will discuss spontaneous pneumothorax and in the subsequent issue I will discuss epilepsy. Spontaneous pneumothorax The lung is an elastic organ that is effectively trying to collapse all the time. What stops this from happening is maintenance of contact between the lung and chest wall with a small layer of fluid lubricating this contact area in the so-called pleural space. It is a bit like two sheets of glass stuck together with a thin film of water in between. They can slide on each other but are very hard to pull apart. A pneumothorax is a collapse of the lung because of air getting into the pleural space thus breaking this contact. It can occur through a variety of causes, including trauma (such as a broken rib puncturing the lung). The most concerning variant from a diving point of view is so-called spontaneous pneumothorax; named “spontaneous” because it occurs with no obvious precipitating event. Patients who suffer a spontaneous pneumothorax are usually found to have small anatomic defects on the surface of the lung that communicate with the airways, and that are prone to rupture with little or no provocation. Once ruptured, gas from the airway can enter the pleural space and the lung can collapse.

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The problem with spontaneous pneumothorax is that there is almost always several of the anatomical defects that caused the event, and patients who suffer one, typically suffer repeat events. Let’s apply the 3 question analysis (above) to spontaneous pneumothorax. The answer to the first question is “yes”. Diving can most definitely “make the problem worse”. If a pneumothorax occurred spontaneously at depth, the ascent in diving would result in expansion of the gas in the pleural space, thus worsening the collapse and potentially causing a “so-called” tension pneumothorax in which the increasing pleural gas pressure pushes on the heart and prevents it working properly. A tension pneumothorax can become rapidly fatal. The answer to the second question is also “yes”. A pneumothorax can occur in diving even in normal lungs (if a diver holds their breath during ascent), and a pneumothorax is thus seen as a diving disorder. This would be much more likely in someone who has anatomic defects in the lung that might rupture with much smaller provocations than are usually required. Finally, the answer to the third question is yes. Clearly if a pneumothorax occurred in the water the diver could be unable to exercise or function adequately. Unfortunately, there is little that can be done to adequately mitigate the risk in diving implied by a previous spontaneous pneumothorax. Some sufferers undergo surgical procedures to stick the lung to the chest wall and prevent collapse, or even to remove segments of the lung that contain the anatomic defects (usually up near the top of the lung). Either procedure may reduce the risk of lung collapse but they don’t completely remove the hazard and they may, in fact, increase the risk of other consequences of lung barotrauma (such as arterial gas embolism). For these reasons, diving physicians (even relatively liberal ones like myself) continue to see previous spontaneous pneumothorax as a contraindication to diving. I am aware that some individuals have chosen to dive despite a history of spontaneous pneumothorax, but they do so at much greater risk, and are unlikely to have found a diving doctor who would endorse what they are doing. The medical community tries not to blindly adhere to old dogma on such issues, and periodically reviews its stance. This was done relatively recently in relation to spontaneous pneumothorax in a very considered and sensible review by colleagues from Duke University in the USA [1]. They were essentially looking for evidence that would support relaxation of our conservative stance on spontaneous pneumothorax but concluded that the current position is essentially sound. If any readers are interested in this article they can email me at sj.mitchell@auckland.ac.nz, and I will send it to them. Reference: 1. Alvarez Villela M, Dunworth S, Harlan NP, Moon RE. Can my patient dive after a first episode of primary spontaneous pneumothorax? A systematic review of the literature. Undersea Hyperb Med. 2018;45:199-208.

PROFESSOR SIMON MITCHELL MB ChB, PhD, DipOccMed, DipAdvDHM (ANZCA), FUHM, FANZCA Simon works as an anaesthesiologist at Auckland City Hospital and is Professor of Anaesthesiology at the University of Auckland. He provides on-call cover for the diving emergency service in New Zealand. He is widely published with two books and over 160 scientific journal papers or book chapters. He co authored the hyperbaric and diving medicine chapter for the last four editions of Harrison’s Principles of Internal Medicine. He has been Editor-in Chief of Diving and Hyperbaric Medicine Journal since 2019. He has twice been Vice President of the UHMS and in 2010 received the society’s Behnke Award for contributions to the science of diving. Simon has a long career in sport, scientific, commercial, and military diving. He was first to dive and identify Zealand, including one in 2002 which was the deepest wreck dive undertaken at the time. He was conferred Fellowship of the Explorers’ Club of New York in 2006, and was the Rolex Diver of the Year in 2015. His most recent expeditions were the Pearse Resurgence cave exploration (New Zealand) in 2020, a project to take arterial blood gas specimens from an elite freediver at 60m 2021, and hunted for a shipwreck in the sub-Antarctic in 2022. three historically significant deep shipwrecks in Australia and New

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2024 SPEAKER LINE-UP

STEVE BACKSHALL JILL HEINERTH • LIZ PARKINSON • PETE MESLEY DR RICHARD HARRIS • ANTHONY GORDON

ANZ/INSPIRATION STAGE

HOLLY WAKELY • DEBORAH DICKSON-SMITH • TERRY CUMMINS RONI BEN-AHRON • NAYS BAGHAI • MATIAS NOCHETTO JAMES HUNTER • DANNY CHARLTON • TORREY KLETT

TECH STAGE

PATRICK WIDMANN • KERRIE BUROW • YANA STASHKEVICH JOHN GARVIN • MIKE MASON • JILL HEINERTH • DAVID STRIKE JOHN KENDALL • DR MATT CARTER

PHOTO STAGE

NIGEL MARSH • MATTY SMITH • DON SILCOCK • MIKE SCOTLAND NICOLAS REMY • BRETT LOBWEIN • CRAIG PARRY • TALIA GREIS

FULL INFO GODIVINGSHOW.COM/ANZ 1 SHOWGROUND ROAD, SYDNEY OLYMPIC PARK, NSW, 2127

DIVE PHOTO GUIDE

GODivingANZ_420x297.indd All Pages

SEPTEMBER 28-29 TH 2024

DIVE PHOTO GUIDE

24/09/2024 10:52

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JUVENILE JURY N owhere is it more important to apply the golden rule: “ Look for what is the same rather than what is different ”, than when examining what maybe a juvenile of a species. Often small and with ill-defined features a juvenile frequently presents a conundrum to the finder. They grow and develop from a shapeless form that we are unable to see in their early most stages. A degree of imagination usually needs to be applied. There are of course many species of tiny sea slugs too, making it all the more difficult. Collecting a portfolio of different stages of maturity is helpful. It’s always tempting to think you have found a new species to add to your list. If it is a juvenile, console yourself with the fact that they are not often observed and to have a record of a different life stage is quite remarkable in itself. From small things - big things grow. Here are just a few. Is It Different? - Is It New? - Maybe It’s A Juvenile

Above : Recent molecular testing has revealed that Hexabranchus is not a monotypic genus and that even the species now identified and separated also have morphotypes (different appearance). Additionally the juveniles, being vastly different to the adult, undergo a raft of changes in reaching maturity. Left : A juvenile and adult of Hexabranchus lacer . Right : A juvenile and adult of Hexabranchus sanguineus .

Above : The dorid Dendrodoris denisoni . Left : the juvenile form has most of the features of the adult but just in a different and more basic form. Right : The adult has more tubercles some of which are compound, additional blue spotting that is more vibrant, a reticulation of thin white lines on the notum and rhinophores with a distinct club. The mantle border though is recognisable having undergone little change.

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Above : Jorunna rubescens is a most unlikely looking discodorid. Left : The juvenile is mostly a furry translucent white with distinct opaque white longitudinal lines, the only colour coming from the internal organs and the tips of the gills. It does have the raised gill pocket and the emergence of the characteristic snout. Right : The fully developed adult with its distinctive dog-like snout and raised gill pocket.

Above : Pleurobranchus peronii is a member of a group called Side-gilled slugs. They have an internal shell remnant often visible through the translucent mantle of the juvenile at Left . The colours of the juvenile are quite different and so too is the texture of the mantle surface. It passes through intermediate colour forms before maturing into the adult at Right . The adult may be one of a number of colours.

Above : This large sea slug is also a species of Side-gilled slug - Pleurobranchus weberi . The juvenile, Left , is translucent with the shell remnant covering the internal organs visible through the mantle. The mantle surface is decorated with a simple reticulation of white with low maroon-coloured tubercles located within. The adult, at Right , is almost totally maroon coloured with a series of white concentric circles.

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Miamira magnifica : The juvenile of the species, at Left , exhibits all the characteristics of the adult with ridges, lumps and mantle edge scalloping, but is underdeveloped and of simpler colouration. The adult, at Right , however by maturity, has undergone a virtual explosion of colour and patterning development along with the enlargement of ridges and prominences on the dorsum.

Above : Pteraeolidia semperi . Although the example on the Left is not technically a juvenile it is essentially how one would appear. It has not as yet taken up the zooxanthellae from its prey, to farm in its cerata, hence their lack of colour. The adult, at Right , grows by lengthening and adding more and more rows of cerata, stocking its cerata with zooxanthellae and developing distinctive patterning on its sides and dorsum.

Above Left : A juvenile Bornella anguilla cannot be mistaken for any other species. It bears all the hallmarks of the adult of the species in features, colouration and patterning. Above Right : Not every tiny sea slug is a juvenile. The tiny Vayssierea felis is usually noticed as a minute orange dot under intertidal rocks. It is so small it does not require a gill for respiration.

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The Turtle Detective Text and photos by Mike Scotland

This large Female Green turtle with two remora from Wakatobi Home Reef could be forty years old.

O ne of the greatest natural history detective stories I am aware of is the work done by Col Limpus from Mon Repos Turtle Hatchery near Bundaberg, Qld. Col looked into the

breeding habits and protection of Loggerhead turtles more than fifty years ago. In short, he has helped to bring Loggerheads back from the brink of dying out completely here in Australia.

Hawksbill turtles are very fond of sponges as a snack. Fathers Reef Kimbe Bay, Walindi

positively identifiable Loggerheads were recorded back in Qld. That is a marathon voyage and a brilliant result. I regard this as one of the most amazing research projects; A successful and spectacular detective investigation that solved this most difficult puzzle. What happens as they swim from NZ to South America? Who knows? COMPARATIVE ANATOMY I am totally amazed that turtles have bones just like mine. Turtles with shoulder blades? What about the Humerus, Radius and Ulna as well as hands with fingers and even fingernails. Yep! It goes on and on… Ball and Socket joints? Yes! The upper arm bone, the Humerus is actually much more powerful than the Thigh Bone because it is responsible for most of the locomotion. In addition, it is useful to measure the age of the turtle using bone density. The fore flipper is much larger than the hind flipper; it is used for swimming and feeding. Marine turtles are unique in that they have both an internal and external skeleton. THE SHELL OR CARAPACE The turtle shell has 13 to 15 large defensive plates called scutes made of keratin. Keratin is the same as your fingernails. These scutes are living armour plates that protect the turtle from predators. The shell is sensitive to touch and has a rich supply of nerves and blood supply to the soft tissue underneath. The mid line of the shell in most turtles has five large central hexagonal scutes, the vertebral scutes. Then, there are four or five large lateral scutes, the costal scutes on each side which are sort of pentagons but are built to complete the shell and adjusted to show no gaps. The perimeter of the shell contains 25 to 28 smaller marginal plates. There is a flexible layer beneath to help disperse forces of pressure. The combination of hexagonal, pentagonal and four sided shapes of these interlocking scutes covers the turtle in a complex but perfect pattern to protect their insides. As always, engineering and mathematical features identified in the construction of turtle shells would reveal mind-blowing science. The turtle has experimenting with dome structures, material science in a very complex balance. It could well have potential for engineers to improve dome structures. Mother Nature mastered it millions of years ago. All turtles have thirteen to fourteen scutes, twenty eight ridges around its carapace as well as sixty bones The turtle shell includes their rib cage, spine, and sternum. It sits on a bony plate which is supported by very strong broad ribs. The underside skeleton is called the plastron. It is more flexible so that it can expand and contract when the turtle breathes or when it dives deep.

Admiring a beautiful big Green turtle in Komodo.

Col and his team of researchers helped to find answers to difficult questions like ‘How long do sea turtles live for?’ What is their life cycle? Do they return to the same area they were born at for breeding? A quarter of a million hatchlings were tagged over many years. Twenty nine years later, the first batch of adults were identified when they returned to Mon Repos beach. This confirmed ‘site fidelity’ for turtles. That is they return to the beach where they were hatched. He also helped to set up the Mon Repos Turtle Centre at Bundaberg to protect them. We used to dive with Loggerhead turtles on the NE coast of NSW in the 70’s and 80’s. We saw a dramatic decline in numbers. We are told populations decreased by 80%. A very sad experience indeed! The story of migration of hatchlings to adults amazes me. In summer, Hatchlings swim like mad from Mon Repos beach out hundreds of kms to sea. They travel in the open ocean to New Zealand. Around the age of five they turned up in Chile with a shell about 30 cms long. More than twenty years later, Col Limpus’ team proved that the first

Look closely at two nostrils, two large ‘scales’ between the eyes and a relatively small head.

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This juvenile Chelonia mydas from Lady Elliot Island is resting on a Soft Coral.

Turtles struck by propellors of boats may suffer a broken back, damaged vertebrae and spinal cord, broken ribs and a pierced lung. These are catastrophic injuries! They do have a Rib Cage but it is inside the lungs. The ribs are also fused to the inside of the shell so they are rigid. Therefore, muscles between the ribs, the intercostal muscles are no longer needed. Since the lungs are inside the shell, they cannot breathe in using a diaphragm muscle.They do not expand the lungs like we do. Rather, they use abdominal muscles to push against the stomach to exhale and an opposing pair of muscles to enable inspiration. They have a shoulder girdle and a hip girdle. Both of these are actually inside the rib cage. The upper shell or

carapace and the lower shell the plastron are kept apart by a pectoral girdle at the front and the pelvic girdle at the rear, otherwise their insides would get squeezed. Flippers have a classical Pentadactyl Limb with five fingers. These are fused inside the flippers. Bone X-Ray diagrams even reveal a thumb Florida state university has identified one hundred living creatures including parasites living on the skin and scores of types of algae. Bacteria or fungi can cause shells to rot which can be fatal. ADAPTATIONS FOR AQUATIC LIFE Turtles are very well adapted to life in the sea. They swim using mainly the sensitive front flippers. The rear limbs help somewhat and also steer. Females use them to dig nest holes.

Green turtle from Sipidan, East Malaysia. Note the single pair of very large scales between the eyes and the nostrils.

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Judging by the fact that some turtles reach adulthood fairly intact, the defensive armour must be very effective. Although, most do fall to predation especially when young; some adults carry war wounds. Newly hatched turtles have very soft leathery shells. Most are eaten whole by seagulls; Ghost crabs nab new borns on the beach or predatory fish gulp them down in the water. Turtles shells are more hydrodynamic than tortoises. The shell is designed for swimming; streamlining reduces water resistance and saves energy. The carapace is flatter and has a specially adapted hydrodynamic shape. I suspect that the shape of the turtle shell is a perfectly designed masterpiece of engineering; a gift from Mother Nature to enable great ocean swims that many undertake. They have a much shorter neck and they cannot pull their head in like tortoises can. Nostrils or nares are fully closed under the water to avoid water entering the respiratory system. BASIC PHYSIOLOGY They are a reptile and are Cold blooded or more accurately, ectothermic. ‘Ecto’ means external and ‘thermic’ means heat. They take on the same temperature as the water, having little control over their body temperature other than by behavioural means. The three chamber reptilian heart includes two atria and one ventricle which is a reptilian feature. Some turtles can tolerate extremely high levels of Lactic Acid that would be lethal for many other animals. Research into the shell suggests that chemicals are released to neutralized excess lactic acid. Salt balance is controlled using their Tear Ducts or Lachrymal glands. These excrete excess salt as well as

This juvenile Hawkesbill turtle Eretmochelys imbricata from Walindi PNG is resting on a soft coral.

urea. They have a good sense of smell and they can hear low frequency sounds. BREATHING REFLEX They can slow down their heartbeat when they dive deep. In addition, they can change to a much slower rate of oxygen consumption. They deal with cold water by swimming to warmer water or by going into a partial hibernation. In this sleeping state, they can rest for up to seven hours on one breath.

The very famous Digger from the Febrina could bring turtles to you at will. He was often described as ‘the world’s best dive guide’.

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Some turtles can become friendly and unafraid of divers - Fathers Reef PNG

Metabolism is temperature dependent. It speeds up in warmer water and slows in cool water. This includes digestion rate, oxygen consumption, cell growth and more. Turtles in cold water, say 12 degrees, really slow down. FEEDING Loggerhead turtle has a large broad head with powerful jaws and no teeth. They can crush with 500 lbs of force to crush bivalves and cunjevoi. Males have strong and longer keratin nails on front flippers that can ‘hold’ food whilst they chew. They eat a large variety of food from shells, corals, cunjevoi, sponge jellyfish, sea urchins. Some can filter out

solids in the throat such as crushed shells which are spat out. SEXUAL REPRODUCTION Males have a much larger tail. One male turtle I saw at Great Detached reef on a night dive had to be older than me. It had an enormous tail. I knew that he had swum many hundreds of nautical miles to attend the annual turtle love in. His mission was to ensure that future generations of Green turtles is secured. Many thousands of turtles had come here for the world’s largest annual breeding aggregation for Green turtles. Females release a special sexual pheromone to attract males when they are ready to mate. Females lay countless

Above: This massive male Green turtle travelled hundreds of kms for the annual breeding at Raine Island - GBR Right: Adult males have a prominent tail that looks like a fifth leg. Their penis is in the tail to give it extra length to allow transfer of sperm to the female around the shell. Raine Island - GBR 2023

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eggs in thousands of holes in the sand. This takes one to two hours.They dig these holes using their hind flippers. They have been observed to display mating induced ovulation. That is after they mate, the female releases eggs. Females can store sperm, She often mates with several different males. Competing males will bite the flippers of a mating male and can inflict serious damage. It is most distracting and painful for the suitor. At Mon repos in Bundaberg, Green Turtle female and a Loggerhead mated in 1990 and produced offspring. One known inter bred turtle died at 29 years old and the other two were infertile. Research by Couper and Fitzsimmons tells us that all six species have interbred in the wild. Most commonly Hawksbill and Loggerheads to develop some fertile offspring. LIFE CYCLE Soft leathery eggs are laid in clutches in a

Dive instructor, Emma Louise, observes a massive female Loggerhead turtle showing the huge head. Byron Bay.

I was diving 70 Nautical miles off Bundaberg in January. As I entered the water for the night dive in the late twilight, I saw more than twenty new born Loggerhead turtles over the first five minutes swimming frantically close to the surface. I captured one and was amazed to feel how soft its carapace was. Otherwise, it was a perfect miniature turtle, hell bent on distancing itself from Mon Repos beach south of Bundaberg where it had hatched a day or two earlier. Loggerheads live in the open ocean until they reach juvenile age, and then they migrate to near shore waters after five years before returning to thier place of birth. BARNACLES Turtles develop growths on the carapace including dense foliage of alga and barnacles. If you thought about removing barnacles from a turtle to save it, it would cause

nest. The loggerhead’s sex is dictated by the temperature of the underground nest. Incubation temperatures generally range from 26–32°C. Eggs kept at a constant incubating temperature of 32°C become females. Eggs incubating at 28°C become males. An incubation temperature of 30°C results in an equal ratio of male to female hatchlings. Hatchlings in the centre of the clutch tend to be the largest, grow the fastest, and be the most active during the first few days of sea life. Hatchlings dig through the sand to the surface after incubating for 11 to 12 weeks. They hatch at night to increase the chance of escaping predation and avoid getting baked in the hot January sun. Hatchlings swim toward the ocean’s brighter horizon created by moon and starlights off the water’s surface. They swim for about 20 hours, taking them far out to sea. They can detect Earth’s magnetic field using Iron mineral Magnetite. This is called ‘The mad rush’

Hawksbill turtles captivate divers with their friendly behaviour.

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Loggerhead turtles have a massive head and lay eggs on mainland beaches.

more harm than good. It would be painful as well as become a source of infection. LOGGERHEAD The loggerhead sea turtle ( Caretta caretta ) are distributed throughout the world. Loggerhead turtles become sexually mature between 18 and 33 years and live into their sixties. The average weight is 140 kgs but a record shows one at over 400kgs Of the six species of living Cheloniidae. Loggerheads are more closely related to the Olive Ridley and Hawksbill turtles than to the Green turtle.

All living sea turtles are in the family Chelonidae. except the Leatherback turtle. Subspecific classification of the Loggerhead sea turtle is debated. Most authors consider it a single species. Molecular genetics has confirmed hybridization of the Loggerhead sea turtle with the Kemp’s Ridley Hawksbill and Green turtle. The extent of natural hybridization is not yet established; however, second generation hybrids have been reported, suggesting some hybrids are fertile. Loggerheads are the second largest after the enormous Leatherback turtles. Males develop longer claws and a

Loggerhead turtles can grow over 400kg This huge one from Lady Elliot Island is having a snooze.

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