As if the potential for developing decompression sickness or maybe even being left behind by a dive boat weren’t enough, some of the very creatures we divers head below the surface to see pose some danger. Once you leave the relative safety of the topside world and invade the big blue, you’ve got to keep your guard up – you never know when you could be stung, bitten, or worse. So don your diving gear, grab your buddy, and come with us as we set out to dive with some of the world’s most dangerous underwater species. You might be surprised that some of these creatures made it onto this list!
Electric Rays
Graceful, beautiful, and capable of releasing an electric charge up to about 220 volts, electric rays are also known as crampfish or numbfish. Equipped with between 250 and 500 cells capable of emanating electricity, which they use both as a defensive mechanism against predation and as a method of stunning their prey, these fish have disc-shaped bodies that allow them to swim with minimal effort. Never give in to the temptation to touch one of these rays; 220 volts is more than enough to hurt you seriously. In addition, look at the bottom before kneeling or stepping on the ocean floor, since electric rays often camouflage themselves by hiding under the sand.
Treating Electric Ray Shock
A shock from an electric ray will not normally pose a threat to your life, but it can cause serious cramping, which can lead to more problems. If you are shocked, make your way to the surface to recover. Seek medical treatment as soon as possible.
Electric Eels
Also known as knife fishes, electric eels are capable of growing to about 10 feet in length. These nocturnal animals spend the majority of the day hiding in holes; if disturbed they can deliver quite a shock. An electric eel is capable of generating enough electrical discharge to kill a diver; tests have shown that these animals can produce about 500 volts at 1 ampere current (500 watts).
Treating Electric Eel Shock
If shocked by an electric eel, you have the potential to go into cardiac arrest; in fact, if the shock is extensive, you have the potential to die. Internal injuries may occur as well. In this case, prevention is the best treatment; never reach into a space where one of these eels could be hiding, and pay very close attention to your surroundings to avoid accidental contact. If you or a buddy is stung, get to the surface and seek medical treatment immediately.
Octopuses
Often portrayed as cute animals with big eyes and friendly smiles, octopuses can in fact be quite dangerous. Many of them are not poisonous, however there are quite a few venomous species; of these, the Blue Ringed Octopus is the most dangerous as it can inflict a life-threatening sting. As octopuses have no rigid skeletons, they are capable of squeezing themselves into hidden spaces, providing yet another reason to avoid reaching into dark areas.
Treating Octopus Stings
If you are bitten or stung by an octopus, you may experience a wide variety of symptoms that depend largely upon the extent of contact and the species with which you experienced an encounter. Symptoms range from heavy bleeding to itching and redness to simple pain. In the case of a Blue Ringed Octopus sting, numbness, nausea, and compromised vision occur rapidly, followed by difficulty breathing and swallowing. If you or your buddy are stung, get to the surface. Apply pressure on the wound to prevent the venom from circulating throughout the body. If a diver is unconscious, check breathing and pulse. CPR may be necessary.
Surgeonfish
Surgeonfish didn’t get their name for their resemblance to medical professionals; instead, the fish’s name comes from the scalpel-like spines on their sides, which serve to protect them from predators as they forage for algae along the reef. These beautiful fish are fantastic subjects for photos, however it’s best to use caution when diving in areas where they are present, since their spines can cause very deep cuts and puncture wounds.
Treating a Surgeonfish Sting
If you’re stung by a surgeonfish, you’ll regret it instantly. Severe pain, followed by redness, itching, and swelling occur around the site; the presence of salt water only makes it worse. Get to the surface and have any spines stuck in the wound removed. Afterward, clean the area with antiseptic and immerse it in hot water to ease the pain. If bleeding will not stop, apply light pressure for a few minutes.
Triggerfish
Triggerfish are solitary creatures which guard their nests aggressively. Though very beautiful, and though extremely photogenic, these fish do not like divers and will defend their territory without a second thought. If you are bitten by a triggerfish, you will need to make your way to the surface for treatment as their bites are poisonous.
Treating a Triggerfish Bite
If you’re lucky, you’ll receive a warning nip and your injury will be trivial. If you are bitten hard, your injuries could be severe. As some triggerfish are ciguatoxic, you should seek medical care if you are bitten.
Some symptoms that accompany triggerfish bites include muscle aches, a burning sensation, itchiness, redness, dizziness, and difficulty breathing. Get to the doctor before things get bad.
Stonefish
Among the most poisonous of all fish, stonefish are extremely difficult to see in most cases. With sharp spines that are capable of piercing wetsuits, fins, BCDs, and other equipment, these fish inflict painful cuts. If you are stung, make your way to the surface for treatment.
Treating a Stonefish Sting
Once at the surface, remove spines and facilitate bleeding to help promote venom release. Next, immerse the wound in hot water to help destroy remaining venom. Get medical attention as soon as possible; if left untreated, a stonefish sting can cause serious tissue damage that can necessitate amputation.
Scorpion Fish
Scorpion fish are among the most poisonous creatures on the planet. Like stonefish, they have a rock-like appearance, and they possess spines which inject venom when contacted. Often found in shallow water, along reefs, and inhabiting shipwrecks, these fish should never be touched. If you are stung, make your way to the surface for treatment.
Treating a Scorpion Fish Sting
Remove any spines and facilitate bleeding to aid in the release of venom. Soak the wound in hot water to destroy any remaining venom and to ease pain. Besides physical discomfort at the injury site, you may experience nausea, rapid changes in blood pressure, paralysis, and even unconsciousness. Get medical help immediately if you or a buddy are stung.
These are just some of the most dangerous animals in the ocean. Be sure to read Part Two of this series to learn about more of the deadliest marine species!