This is the second installment of Liza Copeland's series on cruising dangers. Click here to review Part One.
As cruisers dream of being embraced by tropical sun, gliding through azure seas to yet another idyllic anchorage bordered by sugary sands and shaded by swaying palms, it is easy to forget the biting, stinging, poisoning, and parasitic creatures and plants that abound both in the ocean and ashore.
Australia, for example, has a high percentage of such dangers (much to our children's delight!). So you might think it's a very hazardous place, but suggest that to the people who live there and you'll find them highly amused by the thought. They have essentially learned to avoid these beasties and berries, and so must the rest of us. The list of such dangers is actually surprisingly small and with just a few precautions virtually all of them can be avoided.
We also love to visit remote places, which means we need to prepare in advance and be educated about the potential dangers. Travel books, cruising guides, wildlife reference texts, and information from other boaters, locals, and officials can help keep us all safe. It is also wise to have protective clothing such as reef shoes, gloves, and tongs when exploring tropical shallows, and practice common sense by avoiding dangerous waters or resisting the temptation to pet unknown animals that might carry rabies. Some stings or contact with exotic plant life may cause serious allergic reactions, so having supplies of antibiotics, antihistamines, and white domestic vinegar on hand should be commonplace. Here's a list of the natural dangers that cruisers are apt to encounter:
Sharks Although there are several dangerous sharks in tropical waters, they are rarely a problem in reef areas when one is swimming in daylight and in clear waters. We are avid divers and although frequently see sharks, we've learned only to be concerned by known aggressive species, such as tigers, bulls and hammerheads, or ones we do not recognize, particularly those on the outer reef. Sailors should learn to distinguish these dangerous species by having resource books for the area and talking to the locals, especially fishermen. And having a dictionary of the local language can help one understand the facts correctly!
Be particularly concerned if you notice changes in a shark's behavior. If they become excited, or too inquisitive, then leave the water quickly and move to another area. With a stable dinghy and an outboard you can achieve this easily. Keep in mind that swimming in murky waters or at night, especially in harbors where there is trash floating, or in areas known for sharks, is just asking for trouble. And if you're spear fishing, get the catch into the dinghy as quickly as possible and yourselves too if there is blood in the water.
Whales There are very few authenticated records of whales attacking yachts. Whales are curious and intelligent animals and we always look forward to seeing them. Sadly this is not as often as we would like as it is difficult to spot whales unless the seas are quite calm, although we are fortunate here in the Pacific Northwest to have relatively frequent sightings of the distinctive Orcas. Collisions with whales usually occur because the creature is asleep on the surface. Running into a large whale can cause great damage to both parties; one of the many reasons why someone should be on watch at all times.
Barracuda Barracuda live in tropical waters worldwide except for the western Pacific. They are often portrayed as the wolves of the sea, hunting down and tearing to pieces anything foolish enough to be swimming in their vicinity. Nothing could be further from the truth as far as humans are concerned. Although these fish are cannibalistic and have vicious-looking teeth, attacks by barracuda on people are virtually unheard of, and then usually when they have been attracted by flashy objects such as jewelry.
|"Although these fish are cannibalistic and have vicious-looking teeth, attacks by barracuda on people are rare."|
If you're fishing and you catch a barracuda, it is wise to keep your hands away from their mouths when retrieving a hook! We always dribble a few squirts of alcohol down the gullet and on the gills of all fish. It is instantly effective in making them limp (although large fish may regain consciousness and need a few more squirts); and it's a much more humane way of killing them than bashing them over the head with a winch handle, with blood and scales flying everywhere!
Ciguatera While small barracuda make excellent eating, large barracuda and many other coral reef fish may cause Ciguatera poisoning. Ciguatera is caused from the consumption of tropical and subtropical fish that have accumulated natural toxins from a diet that contains species of the dinoflagellate (algae). These poisons move up the food chain from herbivores to carnivorous fish, with over 400 species implicated, and fish larger than four pounds can contain significant amounts of the toxin. Ciguatera is generally confined to coral reef fish between latitudes of 35 degrees North and South and is particularly common where a reef has been damaged either by natural causes or from blasting to widen a channel. Marine finfish most commonly infected are groupers, barracudas, snappers, jacks, eel, mackerel, and triggerfish.
Ciguatera symptoms include gastrointestinal, neurological, and cardiovascular disorders with numbness, nausea, vomiting and diarrhea. Fortunately, this poisoning is rarely fatal. But the bad news is that it's particularly confusing because the occurrence of the toxic fish is sporadic and not all fish in a given location, even of the same species, will be affected at the same time. To further baffle diagnosis it may take many meals of toxic fish before there is enough toxin in your body to produce symptoms. It is therefore wise if the locals tell you that some fish are affected to avoid all reef fish in the area. Ciguatera poisoning is endemic in Australia, the Caribbean, and the South Pacific Islands, but found all over the tropical world. In our travels, the Tuamotus in French Polynesia were the most severely affected and a local medic told us it was the cause of 80 percent of his cases.
Eels and Stingrays Although moray eels can give one quite a surprise as they dart out unexpectedly from holes in coral, they are not a problem as long as they are left alone. Similarly, stingrays are not aggressive by nature, but they will sting you if you step on the spike in their tail. The sting can cause profuse bleeding and excruciating pain, which is why we always wear shoes and shuffle through the water to startle any stingrays, giving them a chance to flee.
|"Some tropical species of jellyfish are very dangerous, such as the Australian box jellyfish, whose sting can be fatal, and some have as many as 5,000 stinging tentacles."|
Fatal Creatures Some tropical species of jellyfish are very dangerous, such as the Australian box jellyfish, whose sting can be fatal. Slow-moving, the box jellyfish wait for a prey to bump into their tentacles, which have as many as 5,000 stinging cells. As the box jellyfish is almost invisible, it is best not to swim in the jellyfish season in affected waters, particularly in Northern Australia and the adjacent Indo-Pacific region. If you are stung, pour domestic vinegar over the adhering tentacles to inactivate the nematocysts (the stinging cells). Then watch for any difficulty in breathing, speaking, or swallowing. Treat localized pain with icepacks and head to the nearest medical facility. Even Portuguese Man-o-war, which are frequently encountered at sea, can inflict agonizing stings. Being aware of the danger and avoiding it is really the only solution here, but once again, white vinegar can help neutralize the sting.
Most sailors probably haven't heard of stonefish, cone shells, or blue-ringed octopus, but any of these creatures can inflict a fatal wound. Though they're relatively common in Indo-Pacific tropical waters, they should not pose a problem if their presence is known and precautions are taken. Stonefish disguise and conceal themselves on the bottom and reef shoes should be worn when exploring in shallow water, a favorite pastime of our family.
Many cone shells have very attractive markings. Learn to identify the dangerous ones as accidents usually happen to casual, uninformed shell collectors. Again, you should wear reef shoes as they may be hidden in the sand and if you want to examine these mollusks, wear gloves and use tongs.
The blue octopus is found in tidal pools and reef areas in Australia and adjacent waters. They are very shy and will not attack unless handled or provoked. The venom of the blue-ringed octopus is contained in its saliva. It has two components, one effective on crabs but not on humans while the other toxin is similar to that in puffer fish. The bite is usually painless, buy you should watch for breathing difficulties and blueness of the skin as death can occur from respiratory failure. Immediate hospitalization is required.
Lionfish and Pufferfish The brightly colored lion-fish, with their zebra-like stripes, are generally found in coral reefs in the Indo-Pacific region, hovering in caves or near crevices. Their venomous fin spines can give painful puncture wounds, but fatalities are rare. If you're pricked, you should discard the spines immediately, as they can remain active for days. With most fish stings, it's recommended that you immerse the affected area in hot water to improve blood flow and disperse the venom.
Pufferfish are known for their ability to puff themselves up with water or air if threatened. Many species also produce toxic substances that are poisonous if eaten. There are generally several deaths reported in Japan each year from eating puffers that have not been properly prepared. The pelagic sunfish is also a member of this family and should not be eaten.
Sea urchins, coral, and bristle worms are usually nothing more than a painful annoyance if they wound you. (West Indians advocate peeing on an urchin wound as the acid in urine dissolves the calcium spine. Try it, it works!)
Look carefully for sea urchins when wading into the ocean from the beach. When diving avoid touching coral, especially fire coral, to avoid coral burn, which stings painfully and is often slow to heal. The best treatment is the sap of aloe, which grows wild throughout the tropics.
Poisonous Plants The manchineel tree is found throughout the Caribbean, growing near beaches. Size varies from a few feet to over 30. The leaves are small and bright green with yellow stems, and the fruit are like tiny, green apples. Its widely spreading, deep forked boughs provide an inviting cover in a tropical shower but it has a number of effective defense mechanisms that can prove very painful. Not only is the crabapple-like fruit poisonous, the sap from the tree causes painful blisters on the skin, temporary blindness, and terrible pain if it gets into the eyes. Do not stand under a manchineel tree in a rainstorm, or handle the wood or burn it for a barbecue, as even the smoke is dangerous. If you get sap on your skin wash it off in the ocean as quickly as possible.
It is unwise to taste any fruit, nut, berry or fungus that cannot be positively identified. A good source of information, besides books, is at the local market. Here the vendors are generally only too happy to discuss a species, give you some to taste, and also give any warnings. When buying local tropical food always find out how to cook it, as some native foods need special preparation to remove poisons.
There are many plants with poisonous leaves, dangerous thorns and seeds that grip your skin with painful barbs and it is wise taking a local guide when exploring the bush a new area, besides wearing protective clothing.
|"As several tropical diseases can be carried by mosquitoes they should be kept out of the boat (screens are a must)."|
Every sailor has to deal with mosquitoes, sandflies, cockroaches, bees and hornets, scorpions, centipedes, spiders, ticks, lice, and fleas. Except for mosquitoes these can be hazards ashore, but rarely on board provided proper precautions are taken. As several tropical diseases can be carried by mosquitoes they should be kept out of the boat (screens are a must). Repellent, with DEET, should be worn and protective light colored clothing in mosquito-ridden areas, particularly at dusk. Pyrethrum coils, bug zappers, citrosa plants (especially the crushed leaves) are also effective. Contact a local health department regarding the danger of malaria, dengue and yellow fever.Crocodiles and Alligators
In most of the world there do not appear to be any species that are likely to affect the cruiser.
An exception is the marine crocodile, which has made a huge comeback since being protected in Northern Australia. These aggressive and dangerous animals inhabit both fresh and salt waters. Their range includes Indonesia and parts of South East Asia. (Note: Always check your dinghy carefully after being ashore in the evening in these areas as crocs find inflatables very comfortable for a snooze!)
Snakes Many people are fearful of snakes but most are harmless. Where dangerous species are found the local people seem to be able to co-exist with them without problems and no one need feel inhibited about exploring ashore provided they follow local advice, wear sturdy shoes and long pants for additional protection
In the Pacific and Indian Oceans sea snakes are common and one soon becomes used to swimming with these pretty creatures. They are not aggressive and usually avoid contact with people but they are poisonous. As their mouths are small, however, the chances of being bitten are negligible unless one handles them. Besides seeing them in the ocean we found them ashore on beaches. They also like to bask on the dinghy, lapping up the heat from the sun.
Rabies Always assume that rabies is common and avoid contact with both domestic animals, such as dogs and cats, also with wild creatures, even harmless looking ones like bats. Even though domestic animals may have been inoculated for rabies they can still be carriers.
Having taken the necessary precautions we have had very few adverse incidences with beasties and berries in over 100,000 miles of cruising. Perhaps I should qualify that by saying that four members of our family have had no problems. In contrast my poor husband Andy makes up for us all. Not that he isn't prepared, it's just that bugs seem instantly attracted to him. So much so that he is our built-in repellent!"
"It's because I'm so sweet and tender," he frequently consoles himself as he sips his sundowner drink, bathed in DEET and swathed in pajamas from head to toe.