A great article from National Geographic: https://www.nationalgeographic.com/animals/invertebrates/group/box-jellyfish/
About Box Jellyfish
The infamous box jellyfish developed its frighteningly powerful venom
to instantly stun or kill prey, like fish and shrimp, so their struggle
to escape wouldn’t damage its delicate tentacles.
Their venom is considered to be among the most deadly in the world,
containing toxins that attack the heart, nervous system, and skin cells.
It is so overpoweringly painful, human victims have been known to go
into shock and drown or die of heart failure before even reaching shore.
Survivors can experience considerable pain for weeks and often have
significant scarring where the tentacles made contact.
Range and Appearance
Box jellies, also called sea wasps and marine stingers, live
primarily in coastal waters off Northern Australia and throughout the
Indo-Pacific. They are pale blue and transparent in color and get their
name from the cube-like shape of their bell.
Up to 15 tentacles grow from each corner of the bell and can reach 10
feet in length. Each tentacle has about 5,000 stinging cells, which are
triggered not by touch but by the presence of a chemical on the outer
layer of its prey.
Box jellies are highly advanced among jellyfish. They have developed
the ability to move rather than just drift, jetting at up to four knots
through the water. They also have eyes grouped in clusters of six on the
four sides of their bell. Each cluster includes a pair of eyes with a
sophisticated lens, retina, iris and cornea, although without a central
nervous system, scientists aren’t sure how they process what they see.
I get this question a bit during my training courses and kept thinking while I would continue to resuscitate the patient, I really must look into this. No need to do that now after the great article below arrived in my inbox from the guru’s at Royal Lifesaving WA. So here is the answer to this often asked question.
What would you do if you came across an unconscious person needing CPR, but they had a tattoo that said, ‘DO NOT RESUSCITATE’? Would you ignore the tattoo and continue treatment of the casualty? Would there be any legal ramifications of ignoring the tattoo? How would you know if the tattoo genuinely represents the person’s wishes, or if it’s just a joke?
These were questions faced by a team of doctors in the US when a patient was brought into a hospital emergency department. They discovered the words ‘DO NOT RESUSCITATE’ clearly tattooed across his chest, with the ‘Not’ underlined and what they presumed was his signature tattooed underneath the statement.
Faced with the dilemma of not knowing whether the tattoo was sincere, the doctors initially decided to administer some treatment while consulting with their hospital ethics team. The ethics team reviewed the case and advised the doctors to honour the tattoo, because it was reasonable to infer that it expressed the man’s wishes.
The man later died without being resuscitated, and it was discovered that he had, in fact, completed a form expressing his wishes which were consistent with the tattoo. The case sparked international discussion around the validity of these tattoos and whether they are legally binding. So what would happen in Australia?
Hospitals in Australia typically don’t have an ethics team on call to review individual cases. Advance care planning does exist here; however, the laws differ between states and territories. Generally, treating doctors must be satisfied that the person was competent when they made the directive, that they understood the risks of refusing care and that it applies to the current situation – all virtually impossible for a first responder to determine when coming across an unconscious person in need of CPR.
While a Do Not Resuscitate tattoo could in fact represent a person’s wishes, without sighting documentation to verify this we cannot know for sure. Perhaps it was their wish at the time of getting the tattoo, but they have since changed their mind. Perhaps the tattoo was done in jest, or while under the influence. Additionally, the shorter version that simply states the initials ‘DNR’ presents even more ambiguity – it could stand for something else entirely.
First responders in Australia are trained that consent is implied if a casualty is unconscious. We cannot assume to know what the person would want at the time of needing care. It is important to always follow your training and provide CPR if it is required.
Q: Is rockfishing safe? Rock fishing is the most dangerous marine sport in Australia. Every year people die while rock fishing. If you want to rockfish, learn how to minimise the risks.
Q: How can I reduce the risks of rock fishing? The three main ways to reduce the risks of rock fishing are: 1) check and understand the weather conditions and tides before you leave home 2) never fish alone 3) wear the right fishing safety gear.
Q: What is the best type of gear to wear when rock fishing? Wear gear that stops you from slipping into the water or reduces problems if you do go into the surf. Wear shoes with non-slip soles or cleats. Rock plates or cleats are essential on wet, weedy rocks. Wear lightweight clothing and a flotation jacket, so that if you’re swept off rocks, you are buoyant and your clothes don’t drag you underwater. Also, wear head protection because many people who have drowned when swept off rocks have received some sort of head injury.
Q: How do I know if a spot is safe for rock fishing? No place is perfectly safe for rock fishing. To minimise risks, fish only with others in places where experienced anglers go. Spend at least half an hour watching the wind and wave action before deciding whether a place is suitable. Think – what will your fishing spot be like in a few hours time with different tides and a weather change?
Q: Do I need a fishing license when rock fishing? If you’re over 18 and not a pensioner, you need a license to fish. This includes rock fishing and collecting bait. Recreational fishing licences and renewals are processed through the Department of Transport’s DotDirect website. For more information visit www.fish.wa.gov.au
Q: I do enjoy collecting abalone, oysters or other molluscs off the rocks. Is this as dangerous as rock fishing? Whenever you’re on coastal rocks where waves can sweep you into the water, you should follow the same practical guidelines to minimise the risk of being washed away – know and understand the weather conditions and tides, don’t go alone, and wear the right gear, especially non-slip shoes. And remember you need a fishing license when collecting any marine creatures, even by hand.
Q: When and why should I check the weather conditions before I go out boating? A thorough check of weather conditions is vital every time one goes boating. This includes having an appreciation of how the conditions may change throughout the day. A forecast change in weather for example may result in relatively calm conditions in the morning turning into potentially dangerous conditions in the afternoon.
Make sure your vessel is appropriate for the conditions and that you have the necessary experience to handle the forecast conditions. Remember if in doubt, don’t go out.
Q: I’ve been boating for years and can swim OK, do I still need to wear a life jacket? Life jackets or PFDs are an important safety item on any boat and there should be one on board for each person. Children and poor swimmers should always wear a PFD.
Make sure that your life jacket is in good condition, accessible and ready for use or preferably WEAR IT because a life jacket stowed way will not do the job it was designed for.
Q: Is it OK to have a few beers when out on the water in a boat? The combination of wind waves and weather can multiply the effects of alcohol and collectively are known as ‘boater fatigue’. Persons with ‘boater fatigue’ are at a greater risk of drowning should they fall into the water.
The blood alcohol limits are the same on the water as on our roads. A person in charge of a vessel must keep under the 0.05 blood alcohol limit. For commercial vessel operators the lower blood alcohol limit of 0.02 applies.
Q: Where should I bathe and swim at the beach? Bathe and swim between the red and yellow beach flags which indicate beach patrol – bathing and swimming permitted. This area is set up on a daily basis and is constantly under surveillance.
Q: Who watches bathers and swimmers between the red and yellow flags? Professional lifeguards and weekend volunteer lifesavers ensure that people bathing and swimming between the red and yellow flags are constantly under surveillance. Many coastal Councils employ professional ocean lifeguards at beaches 5, 6 or 7 days each week during the Spring, Summer and Autumn seasons or all year round at their most popular beaches. Volunteer lifesavers also attend patrols on weekends during the summer season.
Q: What signs are used at beaches? Australian Standard water safety signs are used at beaches to help provide information, warn people of particular hazards, and to regulate or prohibit some activities. If you are unsure of what a sign means, then ask an on-duty professional lifeguard or volunteer lifesaver.
Q: What if I am unsure about the water conditions? Approach the professional lifeguard or weekend volunteer lifesaver and ask about the conditions.
Q: How do I recognise professional lifeguards and volunteer lifesavers? Professional lifeguards and volunteer lifesavers are located in or near prominently identified equipment including beach shelters, surveillance towers, 4WD vehicles, lifeguard powercraft (RWC or Rescue Water Craft also known as Jet Skis) and inshore rescue boats ( also known as Inflatable Rescue Boats or IRBs) . Council professional lifeguards typically wear long-sleeved white or blue shirts with the word LIFEGUARD in block letters on the front and back and blue shorts/tracksuit pants, full blue uniforms as seen on the popular television series BONDI RESCUE, Volunteer lifesavers wear red and yellow including the red and yellow skull cap.
Q: What is a rip? A rip is a seaward-moving water current. After waves have broken and run shore-wards the accumulated water then moves seaward through a pathway of least resistance which usually is a channel called a rip. Rips move in different directions and flow rates dependent upon the nature of the beach and prevailing conditions including swell direction, wave size and tide level. Rips are the cause of numerous near drowning and drowning deaths because inexperienced people often panic and exhaust themselves struggling against the flow of the rip.
Q: Where do rips occur? Rips occur whenever there is wave activity at beaches – near sandbars and in and around rocks, breakwalls or any permanent ocean floor to water surface fixture in the ocean. When the waves are small the rips usually move in a circular pattern back towards a sand bank within the surf break, however the larger the waves, the stronger the flow, width and length of the rips. During high surf rips can travel past the surf break and are called mega rips.
Q: What do I do if I get caught in a rip? Cross currents and flash rips can cause people to be washed from a bathing and swimming area that is usually a location where waves break on sandbars. Staying calm is essential. Saving energy in not going directly against the rip is important. At beaches where the bathing and swimming area is identified with red and yellow flags, or surfers are nearby, it is best to save energy by floating and request assistance if caught in a rip by waving an arm and calling out for help. Floating and conserving energy is important until help arrives. Struggling against a rip is very exhausting and can lead to panic. Float, relax and save your life if caught in
Q: What equipment do lifeguards use? Council professional ocean lifeguards are trained in beach management and emergency response. They are highly skilled in the use of a range of first aid and rescue equipment including: rescue boards, rescue tubes, neck braces, spinal boards, defibrillators, trauma packs, analgesic gases, radio communication, quad cycles, ATVs & 4WD response vehicles, lifeguard powercraft (RWC or Jetski) with rescue sleds, water safety signage and protective equipment.
Summer is fast approaching and so is the season for drowning deaths and near drowning incidents of West Australian children.
Homeowners need to check now to make ensure that pool barriers comply with Australian Standards and current state regulations. Make sure fences are secure and gates self close and securely latch. Very importantly ensure there is nothing leaning up against the fence or able to dragged over to the fence and used as a step ladder. These are your kids, they are just like you, cunning and smart!
Make sure this summer (and every summer actually) that all children, your own and those of visitors to your home are supervised when in and around water. If you are holding a party and your home has a pool ensure it is securely locked, or, if you plan to use your pool ensure a qualified / competent adult that knows CPR is on duty in the pool area at all times. If you prefer, West Coast Water Safety can provide nationally qualified lifeguards, with Working with Children (WWC) and National Police Clearance, that will not only watch your pool for you but actually get in the water with the kids and entertain them. Imagine that a pool party where all you have to do is entertain the adult guests and relax. Leave the kids and water safety to us!
Children under 5 years of age are the most at risk of drowning. Between 1995 and 1999, 50 children under the age of 14 years drowned in Western Australia, about half of these were under 5 years age. For the same period, 247 children were admitted to WA hospitals after an immersion incident or near drowning.
Maybe you need to think about hiring a professional Lifeguard for the duration of your party. Crazy? Not really, imagine the medical bills, $900+ for the ambulance alone. How much is a life worth?
Need a lifeguard? Let me know and I will arrange it all for you.
Minimise the risk, make sure no one drowns in your pool and make this a good summer for all of us.
Professional Lifeguard West Coast Water Safety www.wcws.com.au
BLUE-BOTTLES: The Portuguese man o’ war (Blue Bottle) is composed of three types of medusoids (gonophores, siphosomal nectophores, and vestigial siphosomal nectophores) and four types of polypoids (free gastrozooids, gastrozooids with tentacles, gonozooids, and gonopalpons), grouped into cormidia beneath the pneumatophore, a sail shaped structure filled with gas.The pneumatophore should probably not be considered a polyp, as it develops from the planula, unlike the other polyps. This sail is bilaterally symmetrical, with the tentacles at one end. It is translucent, and is tinged blue, purple, pink, or mauve. It may be 9 to 30 cm (3.5 to 11.8 in) long and may extend as much as 15 cm (5.9 in) above the water. The sail is equipped with a siphon. In the event of a surface attack, the sail can be deflated, allowing the organism to briefly submerge.
The other three polyp types are known as dactylozooid (defense), gonozooid (reproduction), and gastrozooid (feeding). These polyps are clustered. The dactylzooids make up the tentacles that are typically 10 m (33 ft) in length, but can reach over 30 m (98 ft). The long tentacles “fish” continuously through the water, and each tentacle bears stinging, venom-filled nematocysts (coiled, thread-like structures), which sting and kill adult or larval squids and fishes. Large groups of Portuguese man o’ war, sometimes over 1,000 individuals, may deplete fisheries. Contractile cells in each tentacle drag the prey into range of the digestive polyps, the gastrozooids, which surround and digest the food by secreting enzymes that break down proteins, carbohydrates, and fats, while the gonozooids are responsible for reproduction.
There is a tremendous amount of misinformation, guesstimating and wild wishful thinking involved in wave heights. I thought this article which I have adapted from one the Bureau of Meteorology in Australia put out would be useful. Anyone who visits / uses the beach / ocean needs to understand this concept and the related terminology in use around wave / swell predictions.
A lack of understanding costs the lives of many rock fishermen and boaties every year. It is also the cause of many rescues of swimmers from flash rips. When these large waves hit the beach the massive volume of water has to find its way back out to sea and can / does very easily drag unwary swimmers with it.
Predicting the size of the wind-generated waves that roll in from the sea around Australia is not as hard as you might think—especially if you understand the concept of ‘significant wave height’.
While down at the beach or out on the water you will experience a wide range of wave heights during your activity, and occasionally a genuine ‘big one’, the fabled “rogue”, “bomb” or “wave of the day”. However wonderful a prospect they are to surfers, big waves can pose a serious danger to boaters and fishermen—particularly when they arrive at reefs, bar crossings and deep-water coastlines, where the first indication of a wave’s true size can be as it breaks on the rocks where you’re standing. These are the rock fisher killers and the reason rock fishing is Australia’s most dangerous sport. They are also the cause of many boat capsizes and sinkings due to the simple face that the anchor chain / rope was not long enough to accommodate the big one.
The size and behavior of waves are determined by a range of factors, from the direction of the swell to the speed of the tide, prevailing ocean currents, the depth of the water, the shape of the seafloor, the presence of reefs and sandbanks, even the temperature of the ocean. Ever wondered why on a very large beach all the surfers are crowded into the one or two spots? Well know you know, they have located “The Bank” and are using it to get a good ride. The surfers will also show you where the rips are. They use them as an ocean elevator to get a free ride back out the back for their next ride…
However, there is one factor that rules the size of the waves more than any other—the wind. Waves are caused by wind blowing over the surface of the ocean and transferring energy from the atmosphere to the water. The height of waves is determined by the speed of the wind, how long it blows, and crucially the ‘fetch’—the distance that the wind blows in a single direction over the water.
Naturally, bigger waves result from conditions that cause strong winds to blow for a sustained period over a large expanse of ocean. The resulting waves can travel for hundreds or even thousands of kilometers, smaller waves being absorbed by larger ones, faster waves overtaking slower—gradually growing and arranging themselves into the regular ‘sets’ so familiar to lifeguards, surfers and paddle-boarders. Understanding this along with wave periods, assists the lifeguard to pick the best time and location to head out for a rescue.
The result of these interactions is that it is normal to experience a wide range of wave heights when on the water.
A universal convention to measure wave height
Utilising the standard international convention, the Bureau uses the concept of ‘significant wave height’ to notify ocean-goers of the size of swell and wind waves (or ‘sea waves’) in its coastal forecasts. Significant wave height is defined as the average wave height, from trough to crest, of the highest one-third of the waves.
Devised by oceanographer Walter Munk during World War II, the significant wave height provides an estimation of wave heights recorded by a trained observer from a fixed point at sea. As the following graph shows, a sailor or surfer will experience a typical ‘wave spectrum’ during their activity, containing a low number of small waves (at the bottom) and a low number of very large waves (at the top). The greatest number of waves is indicated by the widest area of the spectrum curve.
The highest one-third of waves is highlighted in dark blue in the graph below, and the average height of waves in this group is the significant wave height:
Significant wave height
This statistical concept can be used to estimate several parameters of the waves in a specific forecast. The highest ten per cent of the waves are roughly equal to 1.3 times the significant wave height, and the likely maximum wave height will be roughly double the significant height. So, if you are going rock fishing or anchoring your boat near a reef etc, remember it is not good enough to simply look at one or two waves and she will right mate…..it won’t be, allow for the bombs or pay the ultimate sacrifice. No matter how good and how fast the lifeguards are, sometimes we will not be able to save you.
Expect double the height, three times a day
While the most common waves are lower than the significant wave height, it is statistically possible to encounter a wave that is much higher—especially if you are out in the water for a long time. It is estimated that approximately one in every 3000 waves will reach twice the height of the significant wave height—roughly equivalent to three times every 24 hours. As a reminder of this important safety concept, the Bureau includes a message that maximum waves may be twice the significant wave height in all marine forecasts.
Most frequent, ‘significant’ and maximum wave heights
When planning a voyage, mariners should not focus exclusively on the significant wave height in a forecast. It is equally important to recognise the concept of the wave spectrum, know the definition of significant wave height, and be able to determine the expected range of wave heights.
Much like the median house price guide in the real estate sector, the significant wave height is intended as an indicative guide that can help you gauge the range of wave sizes in a specific area. While sailors can use the figure to evaluate the safety of an open-water voyage, surfers may use it to rate the likelihood of at least one ‘big one’ arriving while they’re out in the surf. Rock fishers should also be aware of the dangers of the ‘big one’ washing them off the rocks.
Wave forecasts in Australia
Wave height information for seas and swells is included in the Bureau’s Coastal Waters and Local Waters forecasts, covering the Australian coastline and capital city waterways. These forecasts are also transmitted by marine radio (HF and VHF).
Maps and tables of swell and wind wave heights are also available on MetEye—the Bureau’s interactive weather-mapping tool—which allows mariners to ‘play the weather forwards’ over a specific stretch of water for the coming week.
More information on MetEye’s wind and wave features can be found in these recent articles:
Rips can be identified by deeper, dark coloured water, fewer breaking waves and a rippled surface surrounded by smooth water. The most common type is a chanelised rip. These rips occupy deep channels between sand bars and they can stay in the same place for days, weeks and even months.Then there’s boundary rips – which can also be channelised and are found against headlands and other structures reaching out into the ocean like piers and jetties. Sometimes these can be almost permanent. But one of the most dangerous and unpredictable rips is the Flash Rip.
To be able to form, rip currents need breaking waves. It’s the spatial variation in the breaking waves, normally caused by undulations in the sand bars that commonly begins the process of a rip current forming. A flow develops, that moves from the region of intense wave breaking toward the region of reduced or no wave breaking, inside the surf zone This flow is the pathway of least resistance for outgoing water – often a perfect channel – just like a river of the sea.
Typically rip currents are about 10 to 50 metres wide and they can flow anywhere from 50 to 100 metres offshore normally. But Dr Rob Brander has measured rip currents that have flowed 400 metres offshore
To study how rip currents Doctor Rob brander places mobile devices called drifters directly into the currents. These drifters have onboard GPS units that record rip current data such as flow speeds and flow direction both inside and outside the surf zone.
The average rip current flows offshore at speeds of about half a metre to one metre per second. But they all have a tendency to pulse and what that means is that suddenly the rip current can just dramatically double in speed in a matter of thirty seconds and then you’re talking speeds of two meters per second which is literally Olympic swimming speeds.FollowVIDEOTHE FATAL RIPLOADING…
HOW TO SURVIVE A RIP CURRENT
Not all rip currents flow straight out to the breaking waves. Some rip currents flow in a circular movement within the surf zone. These are referred to as rotating eddies. Rip currents are very dynamic – they can change direction quickly.
Rob Brander’s research has revealed that there is no single escape strategy that is guaranteed to get you out of a rip current. Instead you have options based on the conditions and the behaviour of the rip.
The golden rule is to never attempt to swim against the current – they’re just too powerful. Remember to stay calm and focus on floating. Just go with the current and raise your hand for help. Depending on the flow of the rip, floating will normally deliver two scenarios:
A circulating rip current should float you back around to either a sand bank or put you close to breaking waves which will help you get back to shore.
A current that flows directly offshore will normally float you just beyond the breaking waves where the rip will cease to operate. At this point you can either continue to float and wait for rescue or you can swim around the rip and back to shore.
The other option you have – and this applies only to good swimmers – is you can try swimming parallel to the beach in either direction as you float with the current. In some situations this may free you from the rip.
It’s really panic that is the biggest killer when it comes to rips. Rips don’t drown you that don’t pull you under. Panicking will drown you. People panic because they find themselves being taken quickly off shore, the situation is outside of their control, it’s a scary experience.
And what you need to do when you’re caught in a rip is try and take control of the situation yourself. You can float and you can assess what’s going on – do you want to swim this way, do you think that will work. If it’s not working, float a bit and swim the other way or just float. If you’re constantly thinking about the situation and the options you have you’re in control of the situation, provided you haven’t exhausted yourself, but you do not want to panic. Anything that will eliminate panic is the best approach. FollowVIDEOBLACK SUNDAYLOADING…
Each year (on average) rip currents claim more lives in Australia than bushfires, floods, cyclones and sharks combined.
Rip currents are responsible for an estimated 90% of the over 10,000 beach rescues made in Australia each year.
Australia has over 11,000 beaches and scientists estimate that up to 17,000 rips could be operating across Australia’s beaches at any given time
Almost all of Australia’s rip currents fatalities occur on unpatrolled beaches or outside of the red and yellow flags
Less than 4% of Australia’s 11,000 beaches are patrolled by Lifesavers or Lifeguards. This means that there are a lot of beaches and a lot of rips where any beachgoer could find themselves in serious trouble.
Many coastal tourist parks in NSW are situated closest to unpatrolled beaches that are rated as hazardous in terms of rips.
Many of Australia’s rip current drownings take place on isolated stretches of coastline where the nearest patrolled beach is neither close nor convenient.
The simplest way to describe rip currents is that they’re like river of the sea: strong, narrow, seaward flowing currents that extend from the shoreline out beyond the breaking waves. They exist to bring all that extra water that’s coming in with the breaking waves back offshore.
The majority of rip current drowning’s take place underneath bright blue skies, moderate waves and what appear to be perfect beach conditions.
Young males between the ages of 15 and 39 are the most likely to die in rip currents.
Rips are not undertow, they won’t pull you under because there’s no such thing as an undertow. They’re not rip tides because they’re not a tide, they’re a current and they flow pretty steady and they won’t take you to New Zealand.