YOUR WEEKLY DOSE OF WOWZERS AND WONDER FROM THE NATURAL WORLD
Jellyfish might look peaceful, floating about with their colourful bells and flowing tentacles.
But this week’s featured jellyfish can bea real killer—with one of the most deadly venoms in the world—so you definitely don’t want to swim with them!
Get ready to get dangerous as we dive in and explore the world of box jellyfish!
Box jellyfish—also known as sea wasps or marine stingers—are native to warm coastal waters around the world.
They get their name from their light blue, box-shaped bells,and come ina variety of sizes.
The smallest box jellyfish can be as tiny as your thumbnail. The largest can reach as wide as 25 cm (10 inches) in diameter.
Their box-shaped bells have four clusters of eyes with six eyes each. Spaced on each side of the bell, the jellyfish can see in a 90- to 100-degree arc at all times.
At each corner of the bell, the jelly’s tentacles flow out. Each corner can serve as the base of up to 15 tentacles and each tentacle can reach up to 10 feet long!
These tentacles include more than 5,000 stinging cells each.
While not every species of box jellyfish is venomous, those that are pack a serious punch.
Box jellyfish developed this venom to help protect their delicate tentacles when hunting their preferred prey of fish and shrimp.
Large populations of venomous box jellyfish are common in the Indo-Pacific and northern Australia regions.
Their venom attacks the heart, nervous system, and skin.
If a human survives the sting, it can leave a lasting scar that causes considerable pain for weeks.
When swimming in an area with potential box jellyfish populations, wearing lycra products or other skin coverings can provide ample protection from stings.
This is because the box jellyfish’s nematocysts—or stinging cells—aren't triggered by touch, but by sensing chemicals on the skin.
No chemicals mean no stinging!
Their powerful sting isn’t the only adaptation box jellyfish have made to stand apart from their other invertebrate siblings though.
They’re also capable swimmers!
While most jellyfish are subject to the currents they float in, box jellyfish canjet through the water at a speed of 7.5 kilometres (4.6 miles) per hour.
Despite all this, jellyfish live relatively short lives—less than a year in most cases.
This is likely a good thing because warming ocean waters have been attributed to an increase in jelly populations in many parts of the world.
Despite their potent venom, box jellyfish are a favourite snack for sea turtles, whose thick skin and shells render the jelly’s stingers useless.
Box jellies can lose up to 30% of their body weight in a single day if they don’t eat. Talk about an effective diet!
If you’re ever stung by a jellyfish, experts recommend removing the tentacles from your skin and flushing it with vinegar. This will deactivate the stinger cells.
While most jellyfish simply float about, researchers have discovered evidence that Irukandji and Australian box jellyfish actively hunt their prey. That’s quite an accomplishment for a creature with no brain!
See the beautiful but deadly box jellyfish from a safe distance with this creature feature from Maredis.