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-- S t i n g s a n d b i t e s --
click on the question number for the answer |
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| Q 1. | ||
| Do seaweeds ever sting? |
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| Q 2. | ||
| One morning while swimming at the Redington Beach near St. Petersburg, we saw a large school of whip rays. We waited until they had passed before going in the water. Would there have been any danger involved in swimming near them? |
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| Q 3. | ||
| Does the porcupinefish sting when handled? |
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| Q 4. | ||
| Does coral ever sting? |
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| Q 5. | ||
| What is the most dangerous of all stinging fishes? |
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| Q 6. | ||
| Is it true that certain cone shells are capable of fatally stinging a person? |
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| Q 7. | ||
| Does the sting ray possess a true poison? |
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| Q 8. | ||
| What causes "bather's itch"? |
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| Q 9. | ||
| Do sting rays actually produce poison? |
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| Q 10. | ||
| Are octopuses venomous? |
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| Q 11. | ||
| What causes bather's itch? |
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| Q 12. | ||
| I was stung by a Portuguese man-of-war while swimming. What can one do for such a sting? |
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| Q 13. | ||
| Do you have information about the condition known as "hot water" which is encountered by skin divers along the Florida Keys? |
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| Q 14. | ||
| Is the venomous stone fish found around the Bahamas and the Florida coast? |
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| Q 15. | ||
| On several occasions when out diving, I have stepped on the long-spined, black sea-urchins found on the reef. The result was a painful sting, although the pain went away rather quickly. Are these animals poisonous? |
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| Q 16. | ||
| While skin-diving off Key Largo, I swam into some seaweed or some form of algae. It made my skin burn for about an hour and big welts appeared. Later on, my face swelled and a skin condition which looked like poison ivy developed. Can you tell me what may have caused this? |
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| Q 17. | ||
| Will you please give me some information on the sting of the jellyfish Cyanea capillata? |
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| Q 18. | ||
| Could you give me some information on wounds resulting from contact with a stingray? |
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| Q 19. | ||
| While swimming off the Bay side of Plantation Key with my husband and one of our children recently I felt a sting on the left rib. After a while I began itching all over from head to foot and became, a few minutes later, quite nauseated. A doctor gave me a shot for Man-of- War, but I saw no Man-of-War anywhere in the water, although I had previously noticed white balls of jellyfish clinging to the sand and seaweed on shore. What should I do if my children or I am stung again by this "invisible" sea matter? I don't want to discourage them from swimming. |
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| Q 20. | ||
| Large numbers of jellyfish invade the waters off our municipal beach each year and prevent bathing. Last August and September they numbered in the thousands. Is there any way to keep them out? |
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| Q 21. | ||
| I have read that seaweed on the Florida coast occasionally carries parasites that cause "sea bathers' eruption," a local rash that is accompanied by a heavy itch. Might these same parasites cause a systematic reaction of the allergic type? |
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| Q 22. | ||
| Earlier this year while fishing off Freeport, Texas, two of my party received nasty stings from entangled Portuguese Man-of-War while reeling in their lines. I poured a little ordinary lighter fluid over the affected areas on their arms and for both men the response was immediate and gratifying; the stinging stopped at once and permanently. Apparently the naptha in the lighter fluid neutralized or inactivated the toxin, as not enough was used to wash it away. Is this a plausible explanation? |
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| Q 23. | ||
| In August 1965 my wife and I were swimming on a beach in the Gulf of California when we were attacked by swarms of tiny underwater creatures which bit and left little red marks much like mosquito bites. The water was filled with the little animals, which appeared to be crustaceans. I am enclosing several of the creatures that we caught in the hope that you can identify them. |
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| Q 24. | ||
| While fishing in the Bahamas, a friend of mine (a practicing surgeon) was struck in the hand by the tail spear of a small sting ray. Within a few minutes the wound became very painful, and the man suffered nausea, shock symptoms, fever and heavy swelling. My friend contacted a Nassau hospital by radiotelephone and was instructed to take morphine or Demerol for pain relief and antibiotics. The wound drained for more than two weeks and swelling had not completely subsided after three weeks. Has any anti-toxin been developed for sting ray wounds? Have any deaths resulted from such injuries? |
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| Q 25. | ||
| What is the best way to alleviate the stings of the sea nettle? |
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| Q 26. | ||
| The enclosed samples are a lacy, almost white growth found on wrecks near Delray Beach. On contact with skin, it causes a sting and results in an itchy rash. I should like to have it identified, if possible. |
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| Q 27. | ||
| While visiting the Bahamas, I was in clear water about 2 feet deep and knelt on the sea bottom to adjust my flipper. Immediately, I felt intense pain and examination of my leg showed short white spines protruding from my skin in a U-shape about 2 inches long. Then I developed symptoms of shock. Can you tell me what animal I encountered? |
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| Q 28. | ||
| About six months ago, while wading across a shallow reef in Jamaica, my wife and I both stumbled and fell, landing with our hands among the spines of some sea urchins. The impact was forceful and the spines went rather deeply into our fingers in about a dozen places. We applied lime juice and ammonia as the recommended first aid. When we returned home we consulted a physician, who x-rayed the fingers and located the deeply-embedded splinters. He gave us antibiotics and told us that the splinters would dissolve. Our fingers are still sore, stiff, and swollen, and sometimes we have pains to the elbow. Can you advise us as to what can be done about this condition? Also, do the urchins contain a venom? We felt numbness on being stuck, and this still partially exists. |
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| Q 29. | ||
| We spent the last two weeks of May in Mazatlan, Sinaloa, Mexico. The first week we enjoyed surfing. The second week, however, all bathers developed multiple, irregular, raised reddish lesions, varying from 1/2 to 11/2 cms. in diameter, with a few small superficial blisters. These lesions developed only under tight bathing suits, tops or bottoms. The bare areas of skin were uninvolved. The itching was very severe and has persisted for ten days to two weeks. The natives said it was caused by some type of small shrimp. We saw no polyps in the water. There were some irregular patches of red tide in the area, but we sustained no lesions there or around the islands off the coast, only in the surf. I am curious as to what caused these annoying skin lesions. |
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| Q 30. | ||
| During the past two winters I have done some diving in the Bahamas. During both trips, after 6 hours of snorkeling off the beach I broke out with something that would resemble mosquito bites on arms and legs. There was severe itching and a general feeling of slight illness for about five days after breaking out. I treated it with witch hazel. I have been diving for 15 years, all over, and have never gotten anything like this. I assume it is due to some sort of marine life - small jellyfish or something. I am sure I did' not touch fire coral or come into contact with anything noticeable. Do you have any idea as to what they could have been? If so, would a wet suit keep them out? Can you suggest any treatment? |
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| Q 31. | ||
| Can you provide some information about the fire coral Millepora alcicornis? |
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| Q 32. | ||
| Are there any dangerous species of sea anemones along the West Coast of the United States? |
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| Q 33. | ||
| What could have caused the furiously itching, long-lasting welts that we experienced after clamming in shallow water on the south shore of Long Island Sound? |
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| Q 34. | ||
| Could you give me some information or a source of information regarding the sting of the zebrafish? |
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| Q 35. | ||
| While snorkeling off the southern coast of Puerto Rico, I received a mysterious sting on my knee, which later turned red and swelled. Four of us were in the water, none of us noticed anything unusual, and I was the only one injured. Do you have any idea as to what injured me? |
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| Q 36. | ||
| I have heard that gasoline applied to the sting of the Portuguese man-of-war (Physalia physalia) will relieve the symptoms, but I have my doubts as to the safety of using it. Will gasoline work, is it dangerous, and are there any alternative means of treating the sting? |
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| Q 37. | ||
| Great masses of "jellyball" jellyfish (Stomolophus meleagris) frequently can be seen off Cape Lookout, North Carolina. Ate they capable of stinging swimmers or people that handle them? |
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| Q 38. | ||
| During our annual spring vacations at Fort Myers Beach, Florida, we have observed large numbers of rays traveling along the coast only 15 to 25 feet from shore. What causes these gatherings? Also, what precautions can bathers take to avoid being injured by the rays? |
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| Q 39. | ||
| When we were in Hawaii last June, announcements were made on television and in the newspaper warning people not to swim at Kailua Beach, Oahu because of "Stinging Seaweed." Reports said that some people had been stung in the bathing-suit area and had received medical treatment. Can you tell me anything about this seaweed? |
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| Q 40. | ||
| In April, after swimming in the ocean off Palm Beach, I started to itch and had marks resembling insect bites on the parts of my body covered by my swimsuit. What sea creature caused this condition, which lasted for several days? |
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| Q 41. | ||
| Are all jellyfishes venomous? |
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| Q 42. | ||
| In spring 1988, we had an invasion of Portuguese men-of-war along the beach at Vaca Key, Florida. A tourist was stung by a large one and suffered severe pain. In the past, I have recommended the use of meat tenderizer to deactivate the stinging cells. However, at the local hospital, I was informed that all I needed to do was a hot water wash of the area. Is this correct? Also, does stepping on a Portuguese man-of-war and popping the float kill it, or not? |
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| Q 43. | ||
| In spring, we were plagued by sea lice in waters at local beaches. While swimming, paddling, or surfing, I've received numerous rashlike welts that itch and persist for about five days. Can you tell me what organism causes this problem, and how it proliferates? |
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| Q 44. | ||
| If I rub Vaseline on my exposed skin before scuba diving, will it prevent stings from jellyfish? |
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| Q 45. | ||
| I was stung by the tentacles of a Portuguese man-of-war while swimming in waters off Durban, Natal. The sting marks remained on my legs for several years. Was this creature capable of doing even greater harm to me? |
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| Q&A 1. | Do seaweeds ever sting? Fort Pierce, Florida |
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| No, seaweeds do not sting, although in certain cases they may harbor animals that do. A number of jellyfishes and related animals, some of which live attached to seaweeds, do sting or are known to produce an itching sensation on contact with the skin. In addition, some sponges sting, one local red form quite severely, and there is at least one stinging coral as well. Seaweeds, however, are quite harmless although certain kinds may feel rough and irritating to the touch. |
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| Q&A 2. | One morning while swimming at the Redington Beach near St. Petersburg, we saw a large school of whip rays. We waited until they had passed before going in the water. Would there have been any danger involved in swimming near them? St. Petersburg, Florida |
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| The rays you say were in all probability cow-nosed rays, Rhinoptera quadriloba, which frequently travel in large schools. Like the other whip-rays, cow-nosed rays feed on small shellfish which they crush between their flat pavement-like teeth. Although armed with a barbed spine at the base of the long string-like tail, these rays are not aggressive and can only cause ham if carelessly handled or stepped upon. |
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| Q&A 3. | Does the porcupinefish sting when handled? |
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| No, the porcupinefish, Diodon hystrix, does not sting, although the thorny spines which cover its body give this fish ample protection from its enemies. When alarmed, porcupinefishes will inflate their bodies with a large quantity of water, which will make a large specimen swell up to the size of a basketball. The flesh of this fish is poisonous to man, containing a powerful chemical, tetraodontoxin. (See the book Sea Pests by Phillips and Brady, University of Miami Press, 1953). |
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| Q&A 4. | Does coral ever sting? |
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| There is at least one species of stinging "coral", Milipora alcornis. This is not a true coral at all but resembles it closely enough to be identified as such. This takes a great variety of forms on occasion but is usually of a "moose-antler" appearance, though it may grow as an encrustation over dead sea-fans, etc. It is yellowish-brown generally and may be distinguished by the absence of the ridges and pores which usually cover the surface of the true corals. |
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| Q&A 5. | What is the most dangerous of all stinging fishes? |
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| Apparently this is the stonefish of the tropical, Pacific, Synanjeca verrucosa. The sting of this fish has been likened to the bite of a cobra, and intense suffering and possible death will result from accidental contact with its poison-bearing dorsal spines. Because of its protective coloring and its habit of lying motionless on the bottom in shallow water, the stonefish is easily stepped upon by a careless wader. Belonging to the Family of scorpionfishes, the Scorpeanidae, this fish has a number of poisonous but less dangerous relatives in Caribbean waters. |
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| Q&A 6. | Is it true that certain cone shells are capable of fatally stinging a person? |
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| Yes. This has been definitely established. The main shells of this type are the cones from tropical Pacific waters, such as Conus textile and Conus aulicus. In these shells the rasping tongue or radula is modified into a series of long, barbed points, which are connected through their hollow shanks by means of a tube to a poison gland. Severe pain and paralysis generally follow the sting. No cases of stinging from cone shells at local waters have been reported, but they should all be regarded with suspicion. |
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| Q&A 7. | Does the sting ray possess a true poison? |
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| Yes. The sting ray actually does produce a toxic poison, the effects of which vary somewhat among the different species encountered. Scientists are not yet certain whether the poison (found in the slime which covers the stinging spine) is produced directly by the ray or by bacteria living in the slime, but there is more ecidence at present that the first situatuin is the true one. In the newly-released 78-page book Sea Pests by Craig Phillips and Winfield H. Brady (special publication of the Marine Laboratory, University of Miami, 1953) this problem is discussed in some detail, with first-hand accounts of several cases of injury from sting rays. |
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| Q&A 8. | What causes "bather's itch"? Washington, D.C. |
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| Experiments conducted by the Marine Laboratory of the University of Miami have shown that a microscopic organism, the cercaria, stage of a parasitic worm found in certain marine snails, is capable of producing a dermatitis or bathers itch. Experimentally produced itching appears to be identical with that naturally occurring in cases of seabathers itch. A seasonal phenomen, bathers itch occurs only when the temperature of the water reaches 72°F or above. This checks with the fact that the dermatitis occurs during the warmer months of the year. The most effective precaution against penetration of the skin by the parasite is to rub the skin briskly with a towel after leaving the water. |
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| Q&A 9. | Do sting rays actually produce poison? Fort Lauderdale, Florida |
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| There is still doubt that the sting ray actually does produce a toxic poison. Scientists are not yet certain whether the damage done to human tissue is actually due to a poison produced directly by the ray or to bacteria living in the slime that covers the spine. There is more evidence at present that the first situation is the true one, since what seems to be a poison gland is present at the base of the stinging spine in some rays. In the recent book Sea Secrets by C. Phillips and W. Brady (special publication of the Marine Laboratory, of the University of Miami, 1953) this problem is discussed in some detail with first hand accounts of several cases of injury resulting from sting rays. |
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| Q&A 10. | Are octopuses venomous? Portland, Oregon |
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| The second pair of salivary glands of several different kinds of octopuses secrete a poisonous substance, and it is presumed that all octopuses do. The substance is poisonous to lower animals, but generally not to humans. However, any one individual may be highly allergic to the venom, and just as some people barely notice a bee sting others become extremely sick. Octopuses are not the terrors that stories would have them. Nearly every case of a battle between man and octopus has come about because the man went after the octopus or stuck his arm in a hole where an octopus lurked. These creatures are normally shy and retiring. |
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| Q&A 11. | What causes bather's itch? Cleveland, Ohio |
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| Research at the Marine Laboratory of the University of Miami has shown that a microscopic organism (Cercaria) which is a parasite in. marine snails and is capable of producing a dermatitis similar to the skin eruptions commonly associated with swimmer's itch. Bathers itch occurs only when the temperature of the sea water is 22° C or higher, that is in the warmer months of the year. The most effective prophylaxis against penetration of the skin by the cercaria is to dry the skin thoroughly with a towel upon leaving the ocean. The itch is only annoying and does no permanent harm to the bather. |
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| Q&A 12. | I was stung by a Portuguese man-of-war while swimming. What can one do for such a sting? South Miami, Florida |
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| In case of a sting by this animal, the following steps should be taken immediately: 1. Remove all adhering tentacles and jellylike stinging tissue from the affected area. 2. Relieve itching and stinging by application of calamine, alcohol or other soothing lotions. 3. Consult a physician immediately in all severe cases. Recovery from cases of stinging is often slow and secondary infections may result. Skin lesions with surface bleeding may occur at this stage. The poison responsible for the distressing symptoms is a protein-like substance, hypnotoxin, whose exact structure is unknown. The Portuguese man-of-war (Physalia pelagica) is capable of giving a sting even after being washed ashore and apparently dead, therefore extreme caution is urged all bathers When these pests are in evidence. Severe cases of shock accompanied by stomach cramps, nausea, dizziness and pain have been reported after tl1e sting of Physalia. Pain may be felt in the armpit and groin within 15 minutes. In some cases breathing becomes difficult and backache may be experienced. In any event, the Portuguese man-of-war is one of the most violent stinging of all marine invertebrates and should be avoided. |
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| Q&A 13. | Do you have information about the condition known as "hot water" which is encountered by skin divers along the Florida Keys? Miami, Florida |
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| "Hot water" is the term applied by swimmers to bodies of water where they experience an immediate sharp stinging sensation. According to experienced divers this condition occurs sporadically in the vicinity of the reefs from Palm Beach to Key West. Hot water seems to be patchy in distribution and, in calm waters, appears to be confined to the surface for swimmers generally do not experience stinging when they dive. This condition is reported to be most prevalent during June but may be encountered from May through September. Invisible sea creatures popularly called offshore "sea lice" are believed to be associated with this hot water and to be the agents causing the stings. The results of these stings are similar to those resulting from contact with large adult coelenterates, such as the Portuguese man o' war, Physalia physalis, stinging coral, Millepora alcicornis certain jellyfish. Sometimes the irritation produced by the sting disappears in a few minutes but at other times a weal appears at once which later may become postulous. The discrete nature of the sting at least defines the organisms as being a kind which, however small, possess a mechanism powerful enough to penetrate a person's skin. The body surface covered by the bathing suit is affected in addition to the tender exposed surfaces unless the suit fits tightly) in which cases it offers some protection. Marine biologists at The Marine Laboratory have examined samples of "hot water". It was found that, excepting the protozoans, planulae were most abundant in the samples. It was considered that these might have been the planulae of Millepora alcicornis, which forms extensive colonies of known virulence on Florida reefs. However the observations of the planulae only show that they were not siphonophorans and that they were the young of either an athecate hydroid or the millepore. In any case, it seems like1.y that they were the cause of the hot water from which they were collected. This kind of irritation is different from that called sea bather's eruption which is encountered by bathers in beach areas. The latter type of irritation almost always occurs on parts of the body under the bathing suit and results in an acute form of dermatites. |
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| Q&A 14. | Is the venomous stone fish found around the Bahamas and the Florida coast? Nassau, Bahamas |
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| It is always difficult to be sure just which fish is meant when a name such as stone fish is suggested. You probably are inquiring about the poisonous stone-fish. Neither this fish, nor its relatives occur in Florida waters or in the Caribbean. They are, however, widespread in the tropical waters of the Indo-Pacific. |
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| Q&A 15. | On several occasions when out diving, I have stepped on the long-spined, black sea-urchins found on the reef. The result was a painful sting, although the pain went away rather quickly. Are these animals poisonous? Miami, Florida |
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| The long-spined, black sea-urchin, Diadema antillarum, is the bane of reef collectors. Its long, needle-sharp spines are equipped with recurved hooks along the edges. Formerly they were not considered poisonous, but lately evidence seems to point to an actual toxin in the spines themselves. Usually the results are not bad, but occasionally a wound may cause serious trouble and it may be necessary to consult a doctor. |
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| Q&A 16. | While skin-diving off Key Largo, I swam into some seaweed or some form of algae. It made my skin burn for about an hour and big welts appeared. Later on, my face swelled and a skin condition which looked like poison ivy developed. Can you tell me what may have caused this? Jacksonville, Florida |
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| The sea stings you recently experienced probably were caused by the tiny stinging cells (nematocysts) of small plant-like animals called hydroids. Small aquatic animals are "shot" with the nematocysts, immediately paralyzed, and sometimes killed. They then form the food supply of the hydroid. Human beings are not affected so seriously, although individual reactions to the toxins vary. These hydroids often grow on seaweed appearing like small threads. Though so very much smaller, they are related to the Portuguese Man o' War (Physalia). |
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| Q&A 17. | Will you please give me some information on the sting of the jellyfish Cyanea capillata? New York, New York |
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| Very little actual information is available about the intensity of the sting of this jellyfish. However, in subtropical and tropical waters there occurs the jellyfish known as the Portuguese man-of-war, Physalia, about which a good bit is known. The solids contained within the stinging cells of Physalia are lethal to mice in concentrations of approximately one milligram of toxin per kilo of mouse. This places the toxin of Physalia in about the same category as the venom of the cobra. Lest you think the Physalia is unusual among coelenterates, it is reported that off the Great Barrier Reef in Australia there is another small coelenterate form which is reported to be capable of killing a man within minutes of contact. |
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| Q&A 18. | Could you give me some information on wounds resulting from contact with a stingray? Norfolk, Virginia |
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| A wound inflicted by a stingray is quite painful and can put a man out of action. Not only is it immediately painful but it could also cause trouble over a longer period of time because of the presence over the surface of the sting of a slime secretion, heavily populated with microorganisms, some species of which are poisonous. A wound produced by contact with a stingray should be treated like any other deep penetrating wound. If evidence of infection or local inflammation appears, one should consult a physician for further treatment. OLD SAW ABOUT STINGRAY SPINES An old wives' tale was helped along by a recent Sea Secrets answer, according to F. G. Wood, Jr. of Marineland, Florida. Wood, director of exhibits at Marine Studios, writes: "The answer to the question concerning stingray wounds in the June issue perpetuates the old belief that much of the pain and long-term effects of a stingray wound are caused by a slime secretion on the surface of the sting, yet it is now well established that the grooves of stingray spines contain a toxic tissue. "Dr. Findlay E. Russell, discussing stingray injuries in the October 1959 Public Health Reports, states: The toxic fractions of the venom are soluble proteins of average molecular weight In addition to the local effects, the venom produces changes in the cardiovascular, respiratory, nervous and urinary systems. . . The edges of the wound may be discolored, though the discoloration is not usually marked immediately following the injury. However, within two hours the discoloration may extend several centimeters from the wound. Subsequent [tissue mortification] of this area is not uncommon in untreated cases. "Dr. Russell, as well as other authorities, states categorically that every stingray wound should receive professional medical treatment." |
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| Q&A 19. | While swimming off the Bay side of Plantation Key with my husband and one of our children recently I felt a sting on the left rib. After a while I began itching all over from head to foot and became, a few minutes later, quite nauseated. A doctor gave me a shot for Man-of- War, but I saw no Man-of-War anywhere in the water, although I had previously noticed white balls of jellyfish clinging to the sand and seaweed on shore. What should I do if my children or I am stung again by this "invisible" sea matter? I don't want to discourage them from swimming. Tavernier, Florida |
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| Your description of an "attack" by unseen marine organisms resembles the accounts of unfortunate people who have become entangled with Portuguese Man-of-War, Physalia. This is particularly confirmed by your description of general systemic reactions in addition to the local irritation at the point of contact, and your observation of "white balls of jellyfish clinging to the sand and seaweed." It is conceivable that you were stung by developmental stages of the Man-of-War or some related form still too small to be conspicuous to the naked eye but already equipped with the stinging capacity characteristic of adult forms. This painful toxin can be specifically inactivated by the application of an organic solvent such as gasoline, kerosene, xylene or any of this series of hydrocarbons. However, for this treatment to be effective it must be applied promptly. Once the toxin has been introduced into the circulatory system it is necessary to treat the victim symptomatically, a process your physician can advise you about. There is no reason to restrict children's activities unnecessarily, but proper caution should be exercised. The season for the adult Man-of-War in Florida extends from December through May. |
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| Q&A 20. | Large numbers of jellyfish invade the waters off our municipal beach each year and prevent bathing. Last August and September they numbered in the thousands. Is there any way to keep them out? Tampa, Florida |
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| To our knowledge there is no practical means of controlling jellyfish. In your area they are released from budding forms on the bottom in the bay and the Gulf of Mexico at certain times of the year. These jellyfish grow rapidly and soon form the big swarms that come into your waters. In the Chesapeake Bay area the sea nettle, a painfully stinging form, drives bathers from the water for days at a time. No successful means of keeping it out has yet been found. Even small-mesh nets set around the swimming area are only moderately successful. The Chesapeake Biological Laboratory at Solomons, Maryland, has conducted studies of these animals for a number of years. |
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| Q&A 21. | I have read that seaweed on the Florida coast occasionally carries parasites that cause "sea bathers' eruption," a local rash that is accompanied by a heavy itch. Might these same parasites cause a systematic reaction of the allergic type? Irvington, New Jersey |
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| While the intermediate stages of some trematode parasites undoubtedly are responsible for several types of sea bathers' eruption, most scientists believe it is premature to assign all such eruptions to this cause. Irritation can be caused by a host of living and nonliving agencies present in sea water, as well as by the simple osmotic stress of permitting sea water to concentrate on particularly sensitive skin. Planktonic organisms trapped in evaporating sea water on the surface of the skin may cause local irritation, as may the siliceous spicules of some sponges, the spines of fishes and sea urchins, and the stinging nematocysts of coral polyps and other marine coelenterates. It does seem reasonable to assume that trematode parasites, having been destroyed by tissue defenses after penetrating the skin, might liberate sufficient antigenic protein to produce allergic or protein-susceptibility reactions in certain individuals. The likelihood seems relatively remote, however, for the majority of surf bathers. Ocean swimming is a pleasant and trouble-free avocation in both temperate and tropical waters for most people. |
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| Q&A 22. | Earlier this year while fishing off Freeport, Texas, two of my party received nasty stings from entangled Portuguese Man-of-War while reeling in their lines. I poured a little ordinary lighter fluid over the affected areas on their arms and for both men the response was immediate and gratifying; the stinging stopped at once and permanently. Apparently the naptha in the lighter fluid neutralized or inactivated the toxin, as not enough was used to wash it away. Is this a plausible explanation? Houston, Texas |
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| This is not an unexpected response. Physicians often suggest the use of any organic solvent to inactivate the stinging mechanism and perhaps to denature the toxin itself as a preliminary first-aid measure. Our results suggest that alcohol, ether, xylene, gasoline and other organic solvents may inactivate the toxin. The exact mechanism is still being studied. |
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| Q&A 23. | In August 1965 my wife and I were swimming on a beach in the Gulf of California when we were attacked by swarms of tiny underwater creatures which bit and left little red marks much like mosquito bites. The water was filled with the little animals, which appeared to be crustaceans. I am enclosing several of the creatures that we caught in the hope that you can identify them. Redondo Beach, California |
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| The animals that you enclosed are crustaceans of the order lsopoda, that is, they are isopods. These are possibly members of the family Cirolanidae. Whereas many marine isopods are parasites on fish, cirolanids are free-living, preying on dead fish and invertebrates. They will attack anything, however, that does not move around fairly rapidly, and they are well-known for their attacks on humans. Normally they are harmless, simply delivering a nasty bite. They will enter the nose, ears and other body openings, however, and cause considerable discomfort or even minor injury. |
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| Q&A 24. | While fishing in the Bahamas, a friend of mine (a practicing surgeon) was struck in the hand by the tail spear of a small sting ray. Within a few minutes the wound became very painful, and the man suffered nausea, shock symptoms, fever and heavy swelling. My friend contacted a Nassau hospital by radiotelephone and was instructed to take morphine or Demerol for pain relief and antibiotics. The wound drained for more than two weeks and swelling had not completely subsided after three weeks. Has any anti-toxin been developed for sting ray wounds? Have any deaths resulted from such injuries? Arnold, Maryland |
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| No specific anti-toxin is available to counteract the effects of sting ray venom. While the injuries produced by sting ray contacts are always painful, and are sometimes extensive, fortunately they are usually limited to the extremities and so can be readily treated. Most physicians who regularly treat such wounds recommend the use of hot water baths, both to reduce pain and swelling and to promote drainage. It is always necessary to inspect the wound carefully for fragments of the venom sheath that normally enclosed the ray's spine. When found, this must be removed and treatment thereafter is limited largely to symptomatic methods. Deaths from sting ray wounds have been reported, but these have frequently involved such unusual circumstances as the perforation of the anterior abdominal wall by the spine of the sting ray, resulting in a fatal peritonitis. |
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| Q&A 25. | What is the best way to alleviate the stings of the sea nettle? College Park, Maryland |
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| A number of adequate methods exist. The most common is treatment with rubbing alcohol or methylated spirits. In the Miami area some hospitals have achieved good results by applying shaving cream to the affected area and shaving it with a safety razor. Researchers at the Chesapeake Biological Laboratory, who have been working for many years on the sea nettle problem, recommend meat tenderizer. The commercial product is rubbed onto moistened skin until the irritation is gone and then rinsed off. All the above methods depend on destroying or removing the stinging bodies of the jellyfish that have been injected into the skin. These remain reactive for some time after their removal from the animal, pumping poison into the victim. Therefore, the worst thing one can do to a jellyfish sting is to try to wash it off with seawater. It not only keeps the stinging bodies moist and functional, but the agitation incident to washing probably induces undischarged stinging bodies to fire. |
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| Q&A 26. | The enclosed samples are a lacy, almost white growth found on wrecks near Delray Beach. On contact with skin, it causes a sting and results in an itchy rash. I should like to have it identified, if possible. Delray Beach, Florida |
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| The samples are almost certainly hydroids. They are members of the same animal group that includes the corals, the Portuguese man-of-war, and the more orthodox jellyfishes. Hydroids have small stinging elements (about the size of a human red blood cell), armed with coiled penetrating tubules that carry their contained toxin through the skin barrier. It is unlikely, however, that more than temporary discomfort would result from contact with these hydroids. |
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| Q&A 27. | While visiting the Bahamas, I was in clear water about 2 feet deep and knelt on the sea bottom to adjust my flipper. Immediately, I felt intense pain and examination of my leg showed short white spines protruding from my skin in a U-shape about 2 inches long. Then I developed symptoms of shock. Can you tell me what animal I encountered? Rocky River, Ohio |
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| The animal with which you came in contact may have been a bristleworm of the genus Eurythoe, and the short white spines you refer to are the worm's setae, or bristles, which can penetrate the skin like slivers of glass. Typical symptoms of contact with the setae of a Eurythoe bristleworm are inflammation, swelling, numbness, and nausea which may persist for several days. The setae can be removed with the use of adhesive tape, and rubbing alcohol can be applied to the area to alleviate discomfort. Antihistamine tablets may also be helpful but, in any case, the best advice in the event of an injury or reaction is for the individual to consult a physician. |
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| Q&A 28. | About six months ago, while wading across a shallow reef in Jamaica, my wife and I both stumbled and fell, landing with our hands among the spines of some sea urchins. The impact was forceful and the spines went rather deeply into our fingers in about a dozen places. We applied lime juice and ammonia as the recommended first aid. When we returned home we consulted a physician, who x-rayed the fingers and located the deeply-embedded splinters. He gave us antibiotics and told us that the splinters would dissolve. Our fingers are still sore, stiff, and swollen, and sometimes we have pains to the elbow. Can you advise us as to what can be done about this condition? Also, do the urchins contain a venom? We felt numbness on being stuck, and this still partially exists. New Orleans, Louisiana |
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| Your painful experience with sea urchin spines is unfortunately common for visitors and residents of the Caribbean area. As far as is known, none of this region's urchins has the poisonous spines carried by Indo-Pacific urchins. The spines are, however, calcareous and sharp, equipped with basally-directed barbs that insure penetration and retention. They are clothed by an epithelial covering that supports an extensive microbial flora, almost insuring infection. You are presently suffering the results of such infection, possibly by organisms that are unaffected by normal antibiotics. The only treatment is local and symptomatic. Surgery is possible, to remove fragments, but in time the body's reparative processes will dissolve them, if this has not already happened. It must be scant comfort to you, but the development of general symptoms in such cases is distinctly rare, and most people stuck by urchin spines recover in a short time. |
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| Q&A 29. | We spent the last two weeks of May in Mazatlan, Sinaloa, Mexico. The first week we enjoyed surfing. The second week, however, all bathers developed multiple, irregular, raised reddish lesions, varying from 1/2 to 11/2 cms. in diameter, with a few small superficial blisters. These lesions developed only under tight bathing suits, tops or bottoms. The bare areas of skin were uninvolved. The itching was very severe and has persisted for ten days to two weeks. The natives said it was caused by some type of small shrimp. We saw no polyps in the water. There were some irregular patches of red tide in the area, but we sustained no lesions there or around the islands off the coast, only in the surf. I am curious as to what caused these annoying skin lesions. Burbank, California |
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| Your description of the skin lesions and of their location makes it virtually certain that they were caused by a larval form of a parasitic trematode worm. The animals have highly complex life cycles with various stages occurring in different kinds of animals. The definitive host might very easily be a sea bird and the intermediate host might be a fish or a gastropod mollusc. Since the lesions developed only in areas of the skin that, because of their covering, would dry more slowly than the adjacent parts of the body, the organisms were able to embed themselves more successfully there than elsewhere. Once they had penetrated the skin barrier they activated all the body's natural defense mechanisms, the outward manifestation of which was the lesion you described. |
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| Q&A 30. | During the past two winters I have done some diving in the Bahamas. During both trips, after 6 hours of snorkeling off the beach I broke out with something that would resemble mosquito bites on arms and legs. There was severe itching and a general feeling of slight illness for about five days after breaking out. I treated it with witch hazel. I have been diving for 15 years, all over, and have never gotten anything like this. I assume it is due to some sort of marine life - small jellyfish or something. I am sure I did' not touch fire coral or come into contact with anything noticeable. Do you have any idea as to what they could have been? If so, would a wet suit keep them out? Can you suggest any treatment? Mt. Laurel, New Jersey |
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| Some years ago, studies of what was then called "sea bathers' itch" was shown to be caused by trematode parasites, the adults of which normally attack marine birds. The larval stages attach to the unprotected skin of a swimmer and burrow indiscriminately, causing irritation and inflammatory response. Since the biochemistry of the human body is not compatible with their continued development, these irritations are normally short-lived. An indication of the difficulty these organisms experience in penetrating human skin is provided by the distribution of the areas of rash. They are generally found under the belts, swimming shorts, or on other parts of the body that remain wet with sea water for longer periods than uncovered skin. A wet suit might thus help in the invasion. A prompt shower with fresh water would probably destroy the larvae osmotically before they could penetrate the skin. The attack does not persist for more than a few days, and no permanent disability results. |
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| Q&A 31. | Can you provide some information about the fire coral Millepora alcicornis? New Milford, Connecticut |
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| The stinging or fire coral is superficially similar to true coral, but is not closely related. It is actually a hydrozoan. As described in Atlantic Reef Corals by F. G. Walton Smith (University of Miami Press, 1971), it grows into small branches like miniature staghorns or forms encrustations on the surface of old coral or dead seawhips. The polyps are very small, so the skeleton is easily distinguished from true coral by the lack of visible cups. Instead, the light orange-yellow to dark-brown surface is covered by fine, barely visible holes, accounting for the scientific name, Millepora. The stinging cells of this false coral are sufficiently powerful to develop an irritating rash when handled with bare fingers. |
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| Q&A 32. | Are there any dangerous species of sea anemones along the West Coast of the United States? Philomath, Oregon |
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| No. The sea anemones that are known to have the stinging power to affect man adversely are found in parts of the Arctic, North Atlantic, and western South Pacific oceans. Examples are Lebrunia danae, a common species in the Florida Keys and Caribbean; Anemonia sulcata and Adamsia palliata, which occur from Norway to the Mediterranean Sea; Sagartia elegans, commonly known as the rosy anemone, which is found from Iceland to the Mediterranean; and Actinia equina, which inhabits the eastern Atlantic from the Arctic to the Gulf of Guinea, as well as the Mediterranean, Black, and Azov seas. The most venomous species appears to be Dofleina armata, which occurs in waters off the west coast of Australia (see "Anonymous Anemone," Sea Frontiers, Vol. 18, No.6, November-December, 1972). Sea anemones catch food with their tentacles which, as described in the above-mentioned article, "possess various-sized batteries of stinging organs, or nematocysts. These capsules react when touched by shooting hundreds of microscopic stingers into the flesh of the victim. The poison injected by these stingers paralyzes the prey. . . " Thus, if a diver brushes against or touches the tentacles of an anemone possessing a high degree of stinging power, he is liable to activate hundreds of minute stinging organs and suffer a painful injury. |
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| Q&A 33. | What could have caused the furiously itching, long-lasting welts that we experienced after clamming in shallow water on the south shore of Long Island Sound? Miller Place, New York |
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| The unpleasant itching welts were probably caused by larval stages of parasitic flatworms. This is not an uncommon occurrence, particularly on the southeast Atlantic coast, where the affliction is called sea-bather's eruption and is popularly attributed to "sea lice." The adults of these worms are known to attack waterfowl, and the intermediate hosts of some of the species are known to be molluscs. The motile larvae attach to the skin of humans and burrow through it indiscriminately, causing considerable irritation and inflammation. They are incapable of developing in the human body, however, since its biochemistry is not compatible with their continued development. Since the areas of irritation are generally found under swimsuits or other parts of the body that remain wet for longer periods than uncovered skin, one preventive measure might be to shower promptly with freshwater after coming out of the ocean. The larvae might then be killed before they have a chance to penetrate the skin due to the difference in osmotic activity between freshwater and saltwater. Unless secondary infection occurs in the afflicted areas, sea-bather's eruption is normally self-limiting, and the natural defense mechanisms of the body will minimize the discomfort within a few days. |
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| Q&A 34. | Could you give me some information or a source of information regarding the sting of the zebrafish? Oklahoma City, Oklahoma |
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| According to Dangerous Marine Animals by Bruce Halstead (Cornell Maritime Press, Cambridge, Maryland, 1959), zebrafishes (genus Pterois) form one group of the family Scorpaenidae, or scorpionfishes. Zebrafishes, also called turkeyfishes or lionfishes, are beautiful coral-reef fishes that generally inhabit shallow water. The venom apparatus of zebrafishes consists of 13 dorsal, 3 anal, and 2 pelvic spines and their associated venom glands. The long, slender spines are hidden in the delicate-appearing fins. In front of each spine is a glandular groove within which lie the venom glands. The latter are enveloped by thin integumentary sheaths. Some species of zebrafishes possess venom which may be fatal to man. Further information is given in McClanes Standard Fishing Encyclopedia (Holt, Rinehart and Winston, Inc., New York, 1965). |
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| Q&A 35. | While snorkeling off the southern coast of Puerto Rico, I received a mysterious sting on my knee, which later turned red and swelled. Four of us were in the water, none of us noticed anything unusual, and I was the only one injured. Do you have any idea as to what injured me? Ponce, Puerto Rico |
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| Most stings and burns received while swimming in tropical marine waters are caused by the stinging cells (nematocysts) of planktonic hydrozoans and jellyfishes. Some of these are quite small, though still potent, and are virtually transparent, such that it is fairly common to be stung by one without ever seeing it. Such stings, though temporarily painful, usually disappear within a few hours. If symptoms are especially severe or persistent, it is wise to consult a physician. |
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| Q&A 36. | I have heard that gasoline applied to the sting of the Portuguese man-of-war (Physalia physalia) will relieve the symptoms, but I have my doubts as to the safety of using it. Will gasoline work, is it dangerous, and are there any alternative means of treating the sting? New Milford, Connecticut |
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| Two different problems must be solved in treating a sting from the Portuguese man-of-war. Any as yet undischarged nematocysts, the stinging cells, must be removed without causing them to fire, and the effects of the toxin already injected must be countered. Gasoline is of limited value, if any, in solving either problem. Undischarged nematocysts can best be removed by carefully lifting off the tentacle(s) involved (avoid touching them with bare hands) and shaving the attacked area by a razor with a very light blade. To counter the acidic toxin, various basic compounds such as ammonia, milk of magnesia, or solutions in freshwater of baking soda or even crushed antacid tablets are applied. Other materials such as olive oil, alcohol and, most recently, a solution in saltwater of Adolph's unseasoned meat tenderizer, a protein-destroying material (the toxin is mainly composed of short-chain proteins) have all been used with some beneficial results. Though providing some local relief, such remedies will not alleviate the effects of any toxin already injected into the blood stream. In most cases of minor attack, these low levels of toxin can be tolerated but, for severe attacks, a doctor should be consulted. Gasoline has, in the past, been used to treat man-of-war burns despite its limited effectiveness, largely because it was available. According to the American Petroleum Institute Toxicological Review on Gasoline, published in 1967, gasoline is a skin irritant, but requires prolonged exposure before causing severe damage. Gasoline is much more dangerous if swallowed and aspirated into the lungs. With so many alternatives available, there seems to be little reason to use such a potentially dangerous, and largely useless, chemical to treat the wound. |
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| Q&A 37. | Great masses of "jellyball" jellyfish (Stomolophus meleagris) frequently can be seen off Cape Lookout, North Carolina. Ate they capable of stinging swimmers or people that handle them? Charlotte, North Carolina |
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| There is little information available on the toxicity of Stomolophus. What we did find suggested them to be basically nonvenomous; however, some people who are especially sensitive might develop a severe rash by handling them. General information on coelenterate toxicity and descriptions of those species demonstrated to be dangerous are given in Dangerous Marine Animals by Bruce W. Halstead (Cornell Maritime Press, Cambridge, Maryland, 1959). |
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| Q&A 38. | During our annual spring vacations at Fort Myers Beach, Florida, we have observed large numbers of rays traveling along the coast only 15 to 25 feet from shore. What causes these gatherings? Also, what precautions can bathers take to avoid being injured by the rays? Northbrook, Illinois |
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| On the west coast of Florida, breeding aggregations of the cownose ray (Rhinoptera bonasus) form in May and June, and these may have been what you observed. At that time of year, these rays are likely to be encountered along that entire coast. The best way to avoid them is to simply wait for the aggregation to pass by. Other species of rays may also be found at that time in shallow water, giving birth to their young. While cownose rays do possess venomous spines, rays of the family Dasyatidae possess much more effectively placed ones. In addition, dasyatids often lie motionless and partially buried in the sand bottom, making it difficult for beachgoers to notice these common rays of shallow coastal tropical waters. Therefore, it is wise for bathers to shuffle through the sand to frighten unseen rays away and thereby avoid injury. |
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| Q&A 39. | When we were in Hawaii last June, announcements were made on television and in the newspaper warning people not to swim at Kailua Beach, Oahu because of "Stinging Seaweed." Reports said that some people had been stung in the bathing-suit area and had received medical treatment. Can you tell me anything about this seaweed? Long Beach, California |
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| Although we cannot be positive without examining the organism, it is most likely the blue-green alga Lyngbya majuscula. As reported in Dangerous Marine Organisms of Hawaii by Athline M. Clark (University of Hawaii Sea Grant Program, July 1978), this fine, filamentous alga is commonly found tangled with other seaweeds in coral or reef flats, in tide pools, or in deeper subtidal habitats. It can be carried in bulk by waves, however, to beaches, notably Laie and Kailua, Oahu and other windward areas. When fragments of L. majuscula lodge inside a person's bathing suit, they can cause minimal to severe inflammation of the skin, depending on the individual's allergic reaction. Clark recommends that anyone exposed to this alga wash the affected area immediately with soap and water, and change his/her bathing suit. |
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| Q&A 40. | In April, after swimming in the ocean off Palm Beach, I started to itch and had marks resembling insect bites on the parts of my body covered by my swimsuit. What sea creature caused this condition, which lasted for several days? Palm Beach, Florida |
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| Your itching dermatitis was most likely caused by a parasitic trematode worm. Commonly called sea-bather's eruption, the condition is more annoying than serious. Medically labeled cercarial dermatitis, it is caused by the cercaria larvae of marine schistosome worms. The motile larvae attach to the skin of humans and burrow through it indiscriminately, causing considerable irritation and inflammation. They are incapable of developing in the human body, however, since its biochemistry is not compatible. These parasites have a complex life cycle. Sea birds feeding in shallow waters serve as host for the adult worms, which then shed eggs that hatch into larvae that infest marine snails. The larvae then develop tails, leave their snail hosts and, in their free-swimming cercaria stage, seek their sea-bird hosts, but sometimes accidentally penetrate humans instead. In a particular geographic area, the larval worms flourish for only a few weeks. An outbreak occurs when water temperature warms in spring wherever the intermediate snail host is infected and common. There is no way to predict when or where this will happen. Since sea-bather's eruption generally occurs under swimsuits, or on other parts of the body that remain wet for long periods, one preventive measure is to shower promptly with freshwater after coming out of the ocean. The freshwater should kill the schistosome larvae before they have a chance to penetrate the skin. When it does occur, sea-bather's eruption is normally self-limiting, and the natural defense mechanisms of the body will minimize the discomfort within a few days. |
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| Q&A 41. | Are all jellyfishes venomous? Pewaukee, Wisconsin |
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| All true jellyfishes, class Scyphozoa, possess cnidoblasts - cells that contain nematocysts (stinging structures) which may be discharged when stimulated. However, only the nematocysts of certain jellyfish species carry venoms that seriously affect humans. Notable among these is Chironex fleckeri, the sea wasp of Australian waters. The sting of this transparent boxlike jellyfish is usually fatal unless anti-venom is administered instantly. Many of the large jellyfishes, such as the widely distributed sea nettle (Chrysaora quinquecirrha), lion's mane jellyfish (Cyanea caPillata), and mauve stinker (Pelap:ia noctiluca), are also dangerous to humans. The common pink moon jelly (Aurelia aurita) delivers a sting which is itchy, tingly, and uncomfortable, but not dangerous. Another jellyfish-like animal - the hydrozoan Physalia physalis, commonly known as the Portuguese man-of-war - also possesses venomous nematocysts and can pose a threat to swimmers. It is important to remember that different people have different tolerances and reactions. Thus, a sting that may give one swimmer only a nasty welt may put another person into shock and result in drowning. All persons should heed warnings posted by lifeguards at beaches. |
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| Q&A 42. | In spring 1988, we had an invasion of Portuguese men-of-war along the beach at Vaca Key, Florida. A tourist was stung by a large one and suffered severe pain. In the past, I have recommended the use of meat tenderizer to deactivate the stinging cells. However, at the local hospital, I was informed that all I needed to do was a hot water wash of the area. Is this correct? Also, does stepping on a Portuguese man-of-war and popping the float kill it, or not? Marathon, Florida |
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| In treating a Portuguese man-of-war (Physalia physalis) sting, the first step is to remove all tentacles from the victim's skin, because the tentacles contain the stinging capsules, or nematocysts. This removal should be done with something other than bare fingers: a stick, a rag, or a towel. It is possible to further reduce the contact between any remaining tentacle fragments and the skin by carefully shaving the affected area. After removing the tentacles, lifeguards frequently apply a paste made of a papain, containing meat tenderizer and water to the victim's skin to inactivate the toxin. Many chemically basic compounds, such as ammonia and liquid household bluing, also provide rapid relief. One report suggests the use of a paste made from stomach antacids and water or a paste made from the bicarbonate of soda discharge from a common, dry-chemical fire extinguisher and water. Hot water is known to burst the capsule wall of the nematocysts, thereby preventing them from discharging. However, the water temperature must be 115°F to 120°F; and such hot water is rarely found at beaches or on boats. If the water is not hot enough, it will aggravate the condition because, at lower temperatures, freshwater stimulates nematocysts to fire. Stepping on the pneumatophore, or float, will kill the Portuguese man-of-war. One should keep in mind, however, that the nematocysts on the tentacles retain the ability to discharge even in washed-ashore Portuguese men-of-war that are dying or dead and have not completely dried up. During seasons when onshore winds blow this stinging siphonophore onto beaches, it is wise to wear shoes when walking in the littoral zone. |
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| Q&A 43. | In spring, we were plagued by sea lice in waters at local beaches. While swimming, paddling, or surfing, I've received numerous rashlike welts that itch and persist for about five days. Can you tell me what organism causes this problem, and how it proliferates? Lantana, Florida |
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| The "sea lice" probably were larval marine schistosome worms (Austrobilharzia variglandis). Known as cercariae, these parasites cause the condition medically labeled cercarial dermatitis and commonly called sea-bather's eruption. The tadpole-shaped, free-swimming larvae attach to human skin and burrow through it indiscriminately, causing considerable irritation and inflammation. The larval worms can't develop in the human body, however, since its biochemistry isn't compatible. Marine schistosome worms have a complex life cycle. Seabirds feeding in shallow waters serve as hosts for the adult worms. The worms shed eggs that hatch into larvae that infest marine snails. Then the larvae develop tails, leave their snail hosts and, in their free-swimming cercarial stage, seek their seabird hosts. Unfonunately, they sometimes accidentally penetrate human skin instead. In a particular geographic area, the larval worms flourish for only a few weeks. An outbreak occurs when water temperature warms in spring wherever the intermediate snail host is infected and common. When or where this will happen can't be predicted. Sea-bather's eruption often occurs under swimsuits. If taken immediately after leaving the ocean, a freshwater shower should kill any of these saltwater worms that haven't already penetrated the skin. When sea-bather's eruption does occur, the body's natural defense mechanisms alleviate the symptoms within a few days. |
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| Q&A 44. | If I rub Vaseline on my exposed skin before scuba diving, will it prevent stings from jellyfish? Venice, California |
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| Some divers apply Vaseline to their exposed skin to prevent being stung by jellyfishes and small hydroids. These drifting animals possess nematocysts, or stinging cells, that contain barbs attached to threadlike coils. The nematocysts fire when they are contacted by a prey item or by a human. The barbs, attached to the cells by the thread, shoot out like a harpoon. Nematocysts can't penetrate swim skins, wet suits, bathing suits, or other clothing. Because the threads are relatively short, Vaseline may provide a thick enough barrier to prevent stinging of exposed skin, or the nematocysts may get stuck in the Vaseline and not uncoil properly. |
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| Q&A 45. | I was stung by the tentacles of a Portuguese man-of-war while swimming in waters off Durban, Natal. The sting marks remained on my legs for several years. Was this creature capable of doing even greater harm to me? Sunapee, New Hampshire |
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| Yes. The pain of a portuguese man-of-war (Physalia physalis) sting has caused victims to drown. Stings from this animal can be severe. Unlike jellyfishes, the Portuguese man-of-war is not propelled by swimming bells; its movement is controlled by the action of winds on its crested float. It is blown into inshore waters during certain times of the year, depending on the locale. Its fishing tentacles, which contain stinging cells (nematocysts), can trail ten feet or more below the gas-filled float In order to avoid being touched or entangled by the tentacles, swimmers should look for the float which is visible at the water surface although, periodically, part of it dips into the water. In adult Physalia, the float can be 12 inches long. Beachgoers also need to avoid Portuguese man-of-wars that have washed ashore. The stinging nematocysts on the tentacles remain active until they are completely dried up. |
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Rosenstiel School of Marine & Atmospheric Science Library
University of Miami, FL USA 4600 Rickenbacker Causeway, Miami, Florida 33149 Phone: 305 421 4060 Fax: 305 421 9306 E-mail: libcirc@rsmas.miami.edu |
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