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What to watch out for in the water this summer

  • What to watch out for in the water this summer

    In the summer of 1975, Steven Spielberg’s “Jaws” hit theaters and people everywhere were scared to go into the water for fear of being attacked by a Great White. Shark attacks are definitely something to worry about, but water as a whole poses so much more danger than anyone could imagine. Drowning is the third-leading cause of unintentional death around the world. With waterborne illnesses, dangerous sea creatures, and the awesome power of the world’s oceans all looming as threats, it’s important to ask if what’s in the water is really known.

    To help keep everyone safe, Stacker compiled this list of 30 major aquatic threats to be aware of when spending time in the water. No matter if in the ocean, a lake, a pool, or a river, knowing the dangers associated with the specific water activity could be the difference between life and death. Read through the list to learn about the dangers of turtles with bad intentions and what to do when swept up by a rip current in the ocean.

    ALSO: See 50 incredible photos of our oceans

  • Mayflies

    The name “mayfly” isn’t exactly accurate as these inch-long insects aren’t technically flies at all. They’re aquatic insects that live on the bottoms of lakes and streams. They usually hatch in May —although that changes based on environmental factors—and fly for just a single day when they emerge in massive swarms of millions of the creatures. While they don’t bite or sting, getting caught in a mayfly swarm is incredibly unpleasant and experts recommend putting Vicks VapoRub under the nose to distract from mayflies’ fishy smell.


  • Chlorine

    Chlorine is often used as a chemical purifier in swimming pools, but it’s also used as a disinfectant in drinking water. This presents a big problem because chlorine is a poison that’s been linked to higher incidence rates of bladder, breast, and rectal cancers. Even bottled water may contain chlorine, so the easiest way to eliminate the chemical from a personal water supply is to use a carbon-based filter.


  • Pufferfish

    There are 120 species of pufferfish in the world and they’re mostly found in tropical and subtropical ocean waters. Pufferfish—aka blowfish—are easy to identify because they puff up into a ball when threatened. Unfortunately, these fish are dangerous, with enough tetrodotoxin in a single pufferfish to kill 30 people. And there’s no known antidote to the poison.


  • Snapping Turtles

    Ranging anywhere from 8 inches to 14 inches long and 10–35 pounds, snapping turtles are quite large and can be found in freshwater mainly within the eastern United States, specifically South Carolina and Georgia. They’re usually docile, but they start to hiss and snap when they feel threatened. It’s best to leave snapping turtles alone in the wild.


  • Legionella

    Waterborne illness accounts for up to 3.4 million deaths a year and one of the main bacteria found in water is legionella. It’s a bacteria that causes legionellosis which, in turn, becomes Legionnaires’ disease and Pontiac fever. The bacteria can be prevented by keeping water between 68 and 122 degrees Fahrenheit. Diligent water system maintenance and disinfection practices can prevent legionella from becoming a problem.


  • Sea Snakes

    Snakes are scary enough on land, but coming into contact with snakes that can swim brings an added layer of fear to any day at the beach. The yellow-bellied sea snake is venomous and can drift on currents for thousands of miles. Usually found all over the world in Africa, Asia, Australia, Central America, and Mexico, a 25-inch sea snake was recently found in California’s Newport Beach.


  • Crocodiles

    While American crocodiles do exist, their numbers pale in comparison to the saltwater crocodile, found mainly in Australia, India, and Southeast Asia. Weighing 1,000 pounds on average, they lurk just below the surface of the water and snatch anything that moves in their path. Croc attacks are 100 times deadlier than a shark attack—if a person comes into contact with one of them, they should back away slowly and run in a straight line.


  • Reef Stonefish

    It may look like just another part of the reef or rocks on the bottom of the ocean, but reef stonefish are actual fish that can do real damage. The fish is covered in little spikes that contain extremely poisonous venom. Found mainly in the waters of the Indian and Pacific Oceans, the venom causes serious pain that can be abated with hot water and administering an antivenom.


  • Cryptosporidium

    Of all the bacteria to worry about in water, cryptosporidium is toward the top of the list because it can survive contact with chlorine. Known more commonly as “crypto,” these parasites are a leading cause of waterborne illness among humans in the United States. Diarrhea, stomach cramps, and dehydration are just a few of the common symptoms one may notice after coming into contact with crypto. Treatment includes antidiarrheal medicine and drinking safe liquids to replace the fluids lost.


  • Box Jellyfish

    Surprisingly, 95% of a jellyfish is made of water, but the other 5% is what causes problems for jellyfish sting victims. Not all jellyfish are dangerous, but certain species are, including box jellyfish, cannonball jellyfish, lion’s mane jellyfish, and other creatively-named types. The danger lies in the little sacks called cnidocytes, which distribute poisonous venom through rapid stings. Jellyfish stings can be treated with vinegar and hot water, or a specific venom antidote.