The Hard-To-See Animal You'll Want To Try And Avoid When Swimming In Florida

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There are venomous animals in ocean waters all over the world. So, it should come as no surprise that there are dangerous creatures to beware of when swimming at Florida's gorgeous beaches. Several dangerous types of jellyfish are among them, as Florida is home to a wide variety of jellies, along with closely related creatures such as Portuguese man-o-war. What may raise some eyebrows is that some of the most painful stings are delivered by a small, hard-to-see animal you'll want to try and avoid — the box jellyfish.

These tiny terrors have a horrible reputation as being an often unseen yet deadly danger, particularly in the waters of the South Pacific. What many people may not realize is there are several types of box jellyfish — around four dozen or so. Of those, only a handful are actually capable of killing humans. Luckily, the type of box jellyfish found in Florida's waters is not one of the lethal varieties.

However, the fact they are even here is a surprise to many, as box jellyfish aren't native to the nearshore waters of the Sunshine State. While various species of box jellyfish are found in the open ocean waters which bracket the Florida peninsula, species such as the tiny Caribbean box jellyfish, only started turning up along the shorelines in 2009, according to official records. Another type of box jelly found along Florida beaches is the four-handed, which has always lived in the offshore waters of the Atlantic, but has been turning up close to shore with increasing regularity over the past few decades.

All varieties of box jellies have a distinctive shape — a cube-shaped body from which their name is derived. Box jellies also have good vision, and are able to swim with both good speed and control over their directional movement. These qualities set them apart from most other types of jellyfish. However, what distinguishes them the most is the potency of their venom. Thankfully, neither the four-handed nor Caribbean box jellyfish are on the same level as the Australian box jelly, which is the most venomous creature in the world's oceans.

Of the two box jellies swimmers are most likely to encounter along Florida beaches, the four-handed box jellyfish poses a bigger threat. While both species pack a powerful toxic wallop for their body size, the diminutive Caribbean box jellyfish, at less than a quarter-inch in size, is just too tiny to do any major damage. However, they are still capable of inflicting an irritating sting. The body of a four-handed box jellyfish, on the other hand, is about half a foot long, with tentacles extending close to a foot further. Stings from these jellies are known to be excruciatingly painful. Fatalities are extremely rare, but have occurred. 

Given the relatively small size, these dangerous jellyfish are easily obscured in the water. So, it is important to keep a close eye out to be able to spot jellyfish while swimming. You should also heed any posted warning signs at beaches when jellyfish are being seen in abundance. Additionally, avoid swimming in murky, turbulent, or rough water, when jellies are even more difficult to see. Considering even cautious swimmers may get hit, be sure you know what to do if stung by a jellyfish and carry products such as Sting Away Jellyfish Sting Treatment in case you are stung.