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Irukanji jellyfish

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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looking for deeper water
Jan 26, 2002
hi guys

I would just like to tell and warn people about my recent experience with this nasty little jellyfish.

I was recently on an 8 day spearfishing trip north of Cape tribulation FNQ Australia when On the 3rd day I was stung on the neck by an Irukanji jellyfish.

I was diving on a costal reef wearing only shorts and a shirt as the water was too hot for my wettie 33 Celcius, with the northerly winds blowing all the jellyfish had been swept close to shore.

I felt a mild sting on the neck and thought nothing of it simply thinking it was a sea lice or something normal that stings us up here in the tropics. I kept spearing for 5mins got another mackeral and got into the boat.

When I got into the boat I felt a pain coming from my lower back the boys were heading in anyway so I just kept with it not thinking much of it. After 10mins travelling in the boat I was throwing up over the side of the boat and now knew that something was wrong as I NEVER get sea sick. My mate Oscar was getting a bit worried. By the time we got back to the beach I couldn't walk My legs and back were all numb the pain in all my muscles was incredible nothing like I had experienced before I just screamed and wondered how long I would live for.

I remembered Oscar carrying me to the back of the ute and driving to the hospital I was vomiting constantly with sweat pouring off me everywhere. I still couldn't walk when we got to the hospital I was carried in and remember the Doctors putting the drip and other pain killing needles into my arm. I don't remember much else other than the intense muscle spasms that lasted over the next 4 hours.

I was released in a wheelchair and am now recovering slowly the pain and muscle spasms slowly wear off after 48 hours. It has left me with a lot off weight loss and very weak I can only just make myself walk by holding onto something for support.

The Irukanji jellyfish is very small around 2cm in diameter and usually has 4 smallish tentacles that can be 2 - 30cm long. Im not sure where else in the world they are found but here in North queensland Australia they are found not only in the costal waters but also the offshore waters of the Great barrier reef. If planning a diving trip to this part of the world in the future make sure you get a full body lycra suit, and be aware of the signs and symptoms of this nasty little creature.

On a more positive note although my 8 day spearing trip only lasted 3 days I shot plenty of fish in those 3 days and had a great time camping in a very remote area. Another scary highlight for me on the first day was being rammed by a 10 ft Tiger shark whilst I was fighting a fish from the surface, the shark just hit my fin and pushed me out of water a little then took off with speed it could have taken my leg if it wanted too but luckily I kept all my limbs plus all the fish I had on my floatline he didn't take any of them. :confused:

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man, what a story...Im glad that you have recovered well after that insident with the jelly fish.
I have had encounters with so may jelly fish that you could call that it was a jelly fish soup in the ocean, but never got hurt so bad, maybe the ones that we have are not that poissonous.

Still, we always had this motto : when in contact with a jelly fish or with some sort of anemonae (when reef-cave hunting), as soon as possible get either vinegar or pee in the affected area.
That helps a lot, and maybe that can also help a bit with the sort of jellys that you have over there.

Anyway, keep well


Yeah mate we have many different kinds of jellyfish over here. Most dives we swim through hundreds of them, but the two that an cause death are the Irukandji, and the box jellyfish. The others sting us which only last for a couple of minutes but the Irukandji and Box jellies are responsible for quite a few deaths here in North qld.

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Andrew - that's a pretty harsh story. I hope you recover quickly and completely.

I have a question for you about how far South these Irukandji jellyfish can be found, are they encountered in the Brisbane area? The box jellies don't worry me that much but the thought of these little buggers is another thing entirely:(


sorry to hear that mate...wish you well recovery.

Its very intersting first you get annoyed by tiger, than jellyfish.... Fortunatelly we don't have jelly fish here. At least i couldn't see even one of them up to date...

Thanks guys for your support.

Ash I printed some info on the net last night about them and it says they are found as far south as Childers on the queensland coast. Not sure exactly where childers is but pretty sure its like halfway between Brisbane and Rockhampton.

Murat sometimes I think they should rename Murphy's law Andrew's law in that anything that can happen will surely happen :D


Ps I eargerly await my Matrix fins
Glad you made it through the experience, as you note, not everybody does! First the Tiger and then the jellyfish! Someone was taking care of you that day! Take it easy now and recover fully. Your experience will help others planning to dive in those waters.

According to a Discovery Channel show 2005/07/28, they are found in warm waters WORLDWIDE, with a local summer-ish stinging season. The stinging season is reported to be increasing in duration year by year.

The map in particular showed coasts of Australia, Great Barrier Reef, Africa, Florida (and other southern parts of US), and Indian Ocean if I remember correctly. There were other areas marked as well, but I can't be as specific. I would assume in the US this would include Gulf of Mexico and Gulf of California as well (which is where I've done most of my diving, and been stung with no ill effect many times by small-jelly swarms...obviously not Irukanji...I now see this risk in an entirely new light).

There is NO ANTIVENIN, and work is extremely limited on producing one as the researchers apparently have numerous species to contend with, and each species has a unique antivenin requirement. One researcher said there would be no point to producing an antivenin at this point in time because more isolation work was required. The current treatment is symptomatic.

The show indicated treatment with morphine (extremely high dangerous doses) for pain, and antihistamines for blood pressure reduction. For the muscle spasms, they didn't mention any pharmacological treatment, but I understand Valium is often used in OTHER instances of animal envenomation along with morphine. It may be that at the doses of morphine required here, that co-administration of Valium might be too dangerous? In one case noted on the show, they also applied an external neutralizing wash but didn't say whether it actually did any good or not against this particular sting.

They also indicated that some researchers suspect that many cases previously considered drowning at sea might be attributable to this creature.

Based on these new data, I'd think any diver feeling a sharp sting, and unable to absolutely positively determine it is from a benign species, had best head immediately to the dive boat or beach. The onset of crippling symptoms is measured in minutes.

After reading some related posts at another site, I decided to add a few more thoughts to clarify some issues.

The apparently multiple species of this animal could account for different sizes, number/length of tentacles, symptom severity, etc. reported. One post suggested symptoms in cooler waters didn't seem as severe. This may be due to a different species of Irukanji. One post said he saw Irukanji in waters as cold as 20degC. I think it's reasonable to expect there might be significant differences between jellys that prefer 33degC v. 20degC.

The number of fatal encounters has increased dramatically over the past two years. This (in my opinion) may be due to wider range of warm waters/warmer waters, changes in currents, and/or increases in recreational ocean diving/swimming.

It makes sense that in planning a dive trip now, that the onboard medical capabilities of the dive master and boat be fully understood before committing. Many dives can be 10 or more hours away from medical help in undeveloped locations, and the ability to deal with envenomation as well as trauma seems to be increasingly significant.
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yeah one stinged me from lips few months ago, very strange (shocking) experiance. Well it does not took long to find them rofl
Yes, with the emphasis on "die" rather than "happy" :( :)
In Japan this is known and the Habukuragae, America it is the Box Jelleyfish. They are nasty and it is our time of the year on Okinawa so we fish with caution.
DeepThought said:
Well, atleast you have the potential to die happy:

The article basically said that the venom produced in some victims, one effect similar to some drugs used to treat erectile dysfunction.

I'd suspect this "symptom" is probably caused by the massive increase in blood pressure from envenomation. Another report I read said blood pressure DOUBLED. This is why the sting can lead to bursting aneurysms, stroke, cardiac failure, etc. in addition to the narcotic-resistant pain while all this is going on.

If you're looking for more info, be sure to also search on
irukandji = irukanji
scary stuff.

Even scarier to think that if you died in a high blood pressure state, they might have trouble zipping up the body bag, heh-heh.
Someone asked if they get down to Brisbane?
My boss got stung by one in Hervey Bay. that is as far south as I have heard them. Some research only has them listed as far south as Bundaberg or Rockhampton.
I did a little bit of reading on this little bastard. Evidently, intravenous applications of magnesium and magnesium derivatives are being tested and researched as a preliminary antidote or antivenom. I'll try and find the link again. I didn't have the chance to read the whole thing.
When it sting me i felt 10000 volts passed from my lips to my brain, i wonder if memory loss is side effect, since then i lost my abbility to remmember a little :)

No i am not OLD!!! rofl rofl rofl
Re: Irukanji jellyfish-toxicity relative to larger Box Jelly

Ref: my post of July 28th, 2005 (escudo)

I just viewed another documentary on Box jellies and Irukanji/Irukandji, and learned that the smaller cousin to the Box jelly, while about 50 times smaller, is 300 times more venomous.

In addition, instead of injecting the toxins from over the entire surface of the injection barb, the Irukanji's venom is injected like a hypodermic...from the very tip. This suggests to me there is no chance for some of the venom to be depleted in surface clothing. If it penetrates the skin, it is ALL injected into the victim.

This 300:1 toxicity ratio may be offset by some tradeoffs between injector size, number of stingers per tentacle, toxin capacity per stinger, etc., but at the very least it demonstrates the leveraged danger of the smaller jelly and the difficulties of creating universal anti-venins.

(documentary featured Dr. Jamie Seymour, Digital Dimensions Production)
I watched the docu on Discovery and after the two researchers got stung I knew it wasn't something I wanted to tangle with.That jelly is like an invisable killer.
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