NAUI Master Scuba Diver 54 The Diving Environment fish, cowfish, pufferfish, and any fish that you are unfamiliar with unless it is purchased in a reliable restaurant or seafood center. Parenteral Toxins It really is quite easy to reduce your chances of being stung by most creatures in the ocean. The first rule is to always wear protective clothing, (wet, dry, or Lycra suit) whether you are diving in the tropics or temperate waters. Australian divers have found that wearing “panty hose” is an effective protection from their dreaded sea wasp, Chironex fleckeri. A second rule is to make sure you always wear gloves and boots protecting your hands and feet. Finally, look at the bottom before putting your feet down. In this way, you’ll avoid a surprising confrontation with an electric ray, sting ray, stonefish, or scorpionfish. Many animals sting or have some method of introducing venom. From the most primitive of species to the more complex, venomous animals have developed some form of protective apparatus or a unique form of food gathering. Most venomous marine animals can be easily avoided. In some cases, you would have to go out of your way to be harmed by these creatures. For example, no member of the phyla Porifera (sponges) is going to jump off a rock or coralhead to attack you when you’re under water. On the other hand, if a diver should be stupid enough to squeeze a sponge without gloves on, he or she may be in trouble. Sponges have spicules or internal spines that are made of silica or calcium carbonate embedded in the animal’s fleshy body. Only a few sponges are harmful to divers and then only if they come in contact with the skin. The red-beard sponge (Microciona prolifera), fire or dread-red sponge (Tedania ignis), and the poison-bun sponge (Fibulila sp.) all can produce a stinging sensation. Other symptoms include a local sensation of severe burning, swelling (edema), red rash, muscle aches, and joint stiffness (arthralgia). Physicians have treated these conditions with local hydrocortisones, systemic corticosteroids, aspirin, and soothing skin creams. Take pictures of sponges (figure 2-22). Don’t squeeze them. Moving up the phylogenetic scale, the next FIGURE 2-22. SPONGES group that should be discussed is the Cnidarians (Coelenterates), which contain some of the most venomous animals known, although the vast majority are harmless. These animals are mostly marine, including true corals (Madreporia), soft corals (Alcyonaria), fire coral (Hydrozoan), jellyfish (Scyphozoans), and sea anemones (Anthozoans). These carnivorous animals are characterized by having radial symmetry, a gut with one opening and tentacles with stinging cells called nematocysts. It is these nematocysts or stinging cells that deliver the venom. Some can penetrate human skin, others cannot. The amount of venom delivered by different species varies considerably. Consequently, some are harmless, while others are extremely dangerous. Fortunately, stings
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