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Little known hazards on our beaches – 2. Jellyfish

Among other things which can maim or kill, or at least cause excruciating pain, jellyfish deserve a mention too. Although they have always been around, they have been especially prolific this year.  The Gold Coast has been plagued by Blue Bottles and Fraser Island has had an invasion of Irukandji jellyfish.  The box jelly fish known as Stingers which used be seen mainly around the Northern Territory in the Wet Season from November to May, have now extended their range down the east coast as far as the Whitsundays and linger around until July. Warmer ocean temperatures are blamed for this. See the National Geographic for more including excellent pictures

Blue Bottles

I’ll start with the Portuguese Man-o’-War or Blue Bottle (Physalia utriculus) which has been in the news lately because thousands have washed up on the shores around South East Queensland in recent weeks with over 3,000 people being treated for stings on one weekend. 

They are easy to recognise by their blue colour and the fact that they congregate in large numbers. They are also found in New South Wales, Victoria and Tasmania. While not as large or as venomous as  their Atlantic cousins, people can have an allergic reaction and their sting can still be very painful.  Here’s what to do if you are stung:

The Box Jellyfish

The Box Jellyfish is large and clear and comes in around 29 varieties. It is far more deadly because its toxins affect the heart, the nervous system and respiration, and the pain can be so severe that victims may go into shock and drown. According to jellyfish expert, Jamie Seymour, Associate Professor of Tropical Health and Medicine at James Cook University, being in contact with two or more metres of tentacles will kill a person in two minutes. While popular beaches around Darwin often have special stinger nets in the season, this doesn't prevent some tentacles getting through. As the box jelly fish has more than sixty tentacles which can be 3- 4 metres in length, the only real defence is an all- over Lycra body suit, called a Stinger Suit, which are often supplied by dive companies and the like. While not particularly fetching, they will also keep out Ultra Violet radiation which poses the risk of skin cancer and is most likely a fairly effective repellent against romantic encounters as well. As far as stingers go, wet suits will work too.

 In the first instance, remove tentacles and douse with vinegar for at least 20 minutes and be prepared to apply CPR* if necessary. Call emergency services and bandage firmly - not so tightly as to cut off circulation -as for snake bite, and keep the victim still and calm until help arrives.
* CPR - Cardio Pulmonary Resuscitation

NB: Coastal rivers are not necessarily free of stingers either according to the Australian Museum.

Irukadnji Jellyfish

Irukandji  a smaller type of box jelly fish are also on the move. While the most common box jelly fish is large and easily seen, the Irukandji  Jellyfish (Carukua barnesi ) found in tropical waters from  Bundaberg in Queensland to Geraldton in Western Australia, is  a mere 2cm in size but still packs a deadly punch. Not only is it difficult to see in the water, but  the effects of its sting generally do not become apparent until some time after contact. This means that swimmers often do not realise that they have been stung, by which time it may be too late to save them. Typical symptoms which can appear anywhere between 5-45 minutes afterwards include - severe headache or backache, acute pain in the muscles, chest or stomach, vomiting and nausea, profuse sweating, rapid heartrate and high blood pressure and there may even be psychological symptoms such  as anxiety or “feelings of impending doom.”

Treatment is much the same as for other types of box jellyfish. Here’s the advice from the Australian Marine Stinger Advisory Service though note that the use of vinegar is coming under challenge and may not be the answer in all cases. See the full article by North Queensland Tourism here:
  • Wear protective clothing. A full-length Lycra suit reduces the risk of stings by 75%.
  • Carry vinegar when you go swimming or boating to apply to stings
  • Saturate even minor stings with vinegar
  • Don’t go back in the water until you’re sure you are not ill (wait 30 minutes)
  • If in doubt or in distress, seek help ASAP. You may need to go to the hospital for a more thorough check and, if required, medical treatment.