The Australian box jellyfish is considered the most venomous marine animal. They may not look dangerous, but the sting from a box jellyfish could be enough to send you to Davy Jones's locker-a watery grave, that is.
The most common type of stinging jellyfish is the bluebottle. These are found in non-tropical areas, especially along the south-eastern coastline of Australia. Their stings are painful, but they don't usually need medical treatment.
Habu-Kurage and box jellyfish are known to have extremely painful stings, Japanese sea nettle are moderately painful, and moon jellyfish are pretty much painless.
Comb jellyfish are completely harmless with no stingers.
Irukandji jellyfish have the ability to fire stingers from the tips of their tentacles and inject venom. Irukandji jellyfish's stings are so severe they can cause fatal brain hemorrhages and on average send 50-100 people to the hospital annually.
The family of jellies sport bells upto three centimetres long, but it's stings from their sometimes metre-long wispy tentacles (typically used to incapacitate prey) that can cause serious reactions and sometimes fatalities. Jellyfish account for more than 80 known deaths since 1883.
Wear protective clothing such as a full body lycra or neoprene suit, even if in shallow water, as most jellyfish stings occur when wading. This is the number one way of preventing stings, as suits protect up to 75% of the body and cover areas where stings more commonly occur.
But the stingray's excruciating sting does not top Fry's list of the most painful bites and stings dished up by Australian wildlife. That honour goes to the box jellyfish.
3.4) The venom of Irukandji jellies, which are found off the coast of Australia, acts on the nervous system and paralyzes the lungs and heart. Some parts of the body are also more susceptible than others to stings.
1. Box jellyfish – Chironex fleckeri
Known for lurking off the coast of Darwin and northern Queensland, the box jellyfish is one of the most potent stingers in Australia. It has been responsible for 70 deaths in the country and takes victims by wrapping its 3m tentacles around the unsuspecting prey.
Cannonballs are one of the most harmless jellyfish. They usually only cause minor itchiness or irritation when they sting humans, and they play an important role in the diets of leatherback sea turtles and humans.
While box jellyfish are found in warm coastal waters around the world, the lethal varieties are found primarily in the Indo-Pacific region and northern Australia. This includes the Australian box jellyfish (Chironex fleckeri), considered the most venomous marine animal.
The box jellyfish itself grows up to 15 tentacles that can reach up to 3m in length.
Cyanea capillata, or the Lion's Mane Jellyfish, is the largest of all the jellyfish species known to man. At least that we know of, the biggest one in the world stretches across 120 feet, which is almost as tall as a typical skyscraper building. This jellyfish is sometimes referred to simply as the giant jellyfish.
The Irukandji jellyfish has few predators, as its small size and potent toxin make it difficult for other animals to eat. However, ocean sunfish, along with some sea turtles, fish, and sea snakes, are known to prey on the Irukandji jellyfish.
There have been two confirmed Irukandji deaths in Australia. However, the mysterious deaths of several tourists on the Great Barrier Reef are believed to be linked to the stingers.
When properly treated, a single sting is almost never fatal; however, two people in Australia are believed to have died from Irukandji stings, which has greatly increased public awareness of Irukandji syndrome. It is unknown how many other deaths from Irukandji syndrome have been wrongly attributed to other causes.
Where are they found in Australia? Irukandji are usually found in tropical waters, from Bundaberg in Queensland, up around the northern coastline of Australia, to Geraldton in Western Australia. They have been found as far south on the eastern coastline as Hervey Bay, but this is not common.
This includes marine stingers some of which are dangerous, most famously the box jellyfish and Irukandji. These can be found around Tropical North Queensland along the coast as far south as Gladstone, from around October/ November to May/ June.
Irukandji jellyfish are most likely found in tropical Australian waters, from Bundaberg in Queensland to Geraldton in Western Australia, from November to May, though incidents of Irukandji Syndrome in Far North Queensland have been recorded for all months of the year.
The Bluebottle, Physalia physalis, is a common, if unwelcome, summer visitor to Sydney beaches. At the mercy of the wind, they are sometimes blown into shallow waters, and often wash up onto the beach.
Cannonball Jelly
Cannonball jellyfish are the most common jellyfish in our area, and fortunately, one of the least venomous. During the summer and fall, large numbers of this species appear near the coast and in the mouths of estuaries. Cannonball jellies have round white bells bordered below by a brown or purple band.