Boot Key
Boot Key
A Boaters Cruising Guide to Marathon and the Florida Keys ...
This is NOT a medical advice page, but it does review things to watch out for in the water, and in some cases the home "remedies" like the use of meat tenderizer to treat my sea lice welts shown at the left.
(That's the worst itching I've EVER had in my entire life).
          . . . . and Hazardous Marine Life
Sea Lice Welts on Capn Greg
A marine sting or bite is from any form of marine life - here in the Keys its salt-water creatures that create the injury. Most of the time in the Keys, for recreational swimming, diving and snorkeling, the stings come primarily from jellyfish and sea lice, though the following are common marine animals that can cause bite or sting injury:

Jellyfish (not all types sting)           Portuguese man of war (a type of jellyfish)
Stingray (not all rays have stingers)       Sea Lice
Scorpion Fish                                   Stonefish Catfish
Lionfish                                   Sea urchin Sea anemone
Hydroid                                   Moray eel Shark
Barracuda                                   Electric eel Coral - especially fire coral

Click the link at the bottom of this page for pictures and more info on these creatures
(That's still being transferred from the old web site - Please check back later)

Common symptoms are:  Pain,  Stinging,  Swelling,  Redness,  Numbness,  Rash,  Itching,  and Open Wounds (as when you get bit)

What can you do to prevent these?

Wear Water Shoes - we make everyone on our boat do this when we're out exploring the sandbars and islands. Protect your feet.

Don't run into the water or dive headfirst - OK, just use common sense with diving in, and don't run so fast you'll fall down onto sharp things. We make sure it's at least 10 ft deep with nothing sticking up from the bottom (we can see that) before we let the kids dive off the boat.

If you don't know what it is -- DON'T TOUCH IT!  The other part of this is to learn what things are, and what things sting and bite and which don't. A corollary here is DON"T HARASS the wildlife. One teenager found out the hard way when the harmless little bonnet head shark latched onto his shoulder and had to be killed (the shark, not the kid) at the hospital to free him.
Do not swim with open wounds
Don't wear bright shiny clothing, jewelry or equipment - this is primarily true in murky water of low visibility. On the reef in the daytime, where fish can see what you are, it's not as much of a problem but a little shiny lure hanging around your neck could still prompt a fish to go for it.

Don't hang your body parts over the side of the boat while chumming the water!  A couple of kids have lost toes around Boot Key Harbor because of this. This is especially true at dusk and night. - and certainly don't swim while chumming!

Avoid swimming or hanging your body parts in the water during feeding times of dawn and dusk, and avoid night time swimming. (Snorkelers and Divers on reefs can of course enjoy the life after dark, but this is a bit different than just flailing around in the darkness anywhere).

Use the oily lotions before you get in the water to ward off stings from sea lice
Push floating seaweed away from you - it harbors sea lice during that season (mother's day to father's day generally)


These all have tentacles (some so small you couldn't see them) that stick to the skin and fire a little poisonous stinger called a nematocyst. This microscopic little barb injects the prey with a poison (mostly an irritant to humans, but it can get bad depending on what got you). They do this to paralyze little fish and creatures in order to eat them. For us it stings and hurts. The nasty sting from a man of war can be immediate and painful like a blow torch passed over your skin, while the more subtle stings of sea lice can first take a few minutes to develop a very slight itch, then proceed on later to a "drive-you-nuts" itching under the skin. Most exhibit redness and swelling - some more than others. The toxin from the nematocysts is a protein and can be broken down like other proteins using heat, vinegar or meat tenderizers. If the tentacles are still on your skin DO NOT RUB OR MOVE THEM AROUND! - you'll fire more of the nematocysts and make it worse. First inactivate the stingers by pouring vinegar or alcohol over it, then gently lift it from the skin. If none is available and you're in the water then try to gently flush it from your skin in the water with movement, trying not to make it worse. Wash the site gently with soap and water. If you're on a boat try to get vinegar or meat tenderizer on it right away. If you can heat up the vinegar on the boat then get it as hot as you can without risking a burn to the skin. Then pour it over the stings. If you have a hot shower on board then take as hot a shower as you can stand without burning the skin, then do the hot/warm vinegar or meat tenderizer afterwards.  I recently got very bad sea lice stings (Sea Lice are microscopic photoplankton that have nematocysts to sting you. They are NOT jellyfish larvae that get under your skin) and found that meat tenderizer - made into a paste and gently rubbed all over the site - worked much better than vinegar, but it got quite messy when it flaked off.


These all produce venom. The hot water technique described above will help break down the venom. Immerse the area in as hot of water as you can stand (don't burn yourself) for 60-90 minutes. Any pieces of spines or fins should be gently removed while you are wearing gloves, or use small tweezers and pickups. I have to tell you from personal experience, that while perhaps uncivilized, it works - Peeing (urine) on a sea urchin sting provides immediate relief from the burning!

Fisherman's Hospital in Marathon FL recommends that you follow up with a Doctor in these situations:

    You have a sign of an infection (redness, swelling, pain, drainage, fever)
    Uncontrolled bleeding
    If you have not had a tetanus shot in 5 years
    Any problem with the wound that bothers you should be reported to your doctor.

Christmas Boat Parade

Marathon City Marina

Cruising- Waypoints, Anchorages, Marinas

Diving & Snorkeling

Fishing (general)

Marine Stings & Bites

Weather & Tides

Local Keys Links of interest to boaters

Personal Cruising Logs - Pictorial

Personal Boat Library