Other than the risk of scooter accidents, the sea poses the greatest danger to Bermuda visitors, particularly rip currents and undertows found off the South Shore beaches. Drownings are infrequent—and often caused by neither phenomenon. Bermuda has very few “dangerous surf” days, except around hurricanes, which tend to occur at the season’s end in September and October. But inexperienced swimmers should check beach conditions carefully before entering the water and know what to do if they encounter risks.
Rip currents, also called riptides, though they are not tidal, are found at the world’s surf beaches, such as those on Bermuda’s South Shore. They occur as water dumped by breakers at the shoreline returns to the deep sea, “ripping” past natural structures such as rocks, reefs, or sandbars. They are intensified by onshore winds coupled with storm conditions. A rip current is recognizable as a sandy stream of fast-moving water flowing seaward, sometimes splashing as it hits incoming waves. It moves at right angles from the beach—a bottleneck of water stretching up to 200 meters. Swimmers trapped in its movement feel helpless as the surge carries them away from the beach. If you find yourself in a rip current, the number-one rule is: Keep calm. Swimming against the outward-flowing water is exhausting and unproductive, even for strong swimmers. Instead, try to swim across it, parallel to the beach. Rip currents aren’t very wide, so a swimmer can usually reach the tide’s edge, escape its pull, then swim back to safety. If you can’t, don’t panic. The current will eventually release you and will not pull you under.
Undertows or “runbacks,” sometimes mistakenly called “rip currents,” occur by contrast in the rolling surf at the edge of steep beaches, posing a risk to weak swimmers. As a wave is about to break, water from the beach edge is sucked back beneath it. The force of gravity can be strong enough to sweep swimmers off their feet and beneath the crashing surf. The cycle repeats as more waves break, disperse, and break again. The phenomenon, intensified by the angle of a beach, can make even practiced bodysurfers feel a sense of lost control. If you get swept into a series of waves, try to stand up, climb out, or call for help.
May 1–October 1, lifeguards are stationed 10 a.m.–6 p.m. daily at a few popular and family beaches around the island, including Horseshoe Bay , John Smith’s Bay  in Smith’s , and Clearwater, Turtle Beach, and Long Bay in St. George’s. They are on the lookout for swimmers in trouble; wave an arm or call out if you need help. Avoid swimming alone or in rough conditions or storm swells; bodysurfing in hurricane surf, for example, can cause spinal fractures and other injuries. Warning signs and flags are posted in particularly stormy conditions at popular beaches, including Horseshoe Bay  and Warwick Long Bay . A yellow flag crossed by a black diagonal stripe is a warning: See on-duty lifeguards or read information boards posted at the beach entrance. A red flag, for example, around a hurricane’s approach and aftermath, prohibits swimming. A flag atop the lifeguard tower indicates that a lifeguard is on duty.
Shallow water and submerged rocks near favorite swimming holes have left Bermudian teenagers paralyzed, in comas, or severely injured over the years. Accidents commonly occur over the summer holidays as youths show off to friends or spectators from the picturesque overhangs at the edge of popular beaches such as Horseshoe Bay . Travelers would be ill-advised to try high-diving from any points around the island where they are not entirely sure of water depth or the possibility of concealed reefs, sunken objects, or other hazards.
A translucent, frilly edged, violet balloon, the jellyfish known as the Portuguese man-of-war might be considered exquisitely beautiful—if it wasn’t such a menace.
This invertebrate marine animal (Physalia physalis) has a gas-filled, purple-blue float topped by a crest that catches the wind and carries the organism over the ocean. But what you see at the surface is just a fraction of the creature, whose severely poisonous tentacles stretch many feet below. Found in the Gulf Stream and in tropical oceans worldwide, Portuguese man-of-wars travel in schools of hundreds or thousands and can be a swimming hazard on Bermuda’s South Shore year-round, depending on wind direction and other conditions. Onshore winds blow them in. Look for their balloons washed up on the beach (they are difficult to spot on the sea surface) before you enter the water.
Avoid getting stung by the man-of-war’s clinging blue tentacles, which can cause intense pain and occasional blistering, and leave red, whip-like welts on the skin. The impact is rarely more serious, though small children, the elderly, and those with allergies face a greater risk of severe reaction. Notably, the jellyfish is not only harmful when intact, but also when its myriad tentacles are broken into particles by the surf, causing rashes and irritation. Out of the water, the sting is no less severe, so don’t be tempted to pick one up.
The best remedy if you do get stung? Treatment and opinion among medical professionals has evolved over the past 20 years, advising everything from meat tenderizer to urine, and there is still no absolute consensus. The key, says Dr. Edward Schultz, director of Bermuda’s ER, is to deactivate the venom-firing cells, called nematocysts, released by tentacles on to the skin. Schultz recommends that jellyfish victims:
Lifeguards on Bermuda beaches will assist you with first aid if you get stung. While a hospital visit isn’t usually necessary, go the ER immediately if you have difficulty breathing, feel lightheaded or weak, or if the rash spreads. For emergency aid, call 911.
Fire coral (Cnidaria Phylum), a reddish-brown spongy-looking mass on the island’s reefs, can deliver a stinging burn-like sensation. Related to the jellyfish rather than the coral family, it can also scrape the skin. Rule of thumb on the reefs: Don’t touch anything—for your comfort, as well as the reef’s longevity (real corals can die when touched).
Fish to avoid include the porcupine-like lionfish, a poisonous species usually found in Australasia, but which has been spotted in the last few years in Bermuda’s waters. The fish usually avoids human contact, but if touched, it releases venom from its puncturing spines. The great barracuda’s menacing profile is deceptive; despite its ugly toothy grin, this large fish is usually harmless, though they have been known to snap at shiny metal objects, so keep watches and jewelry out of sight. Moray eels may look fearsome, but they mostly avoid human contact—unless you shove a hand into their lair. Do not touch the flat red bristleworm or the related fireworm; their needles leave a rash. Most corals, sea anemones, and jellyfish deposit a poisonous zap on human skin, so try not to touch them. Spiny sea urchins hidden in sea grass also pose a hazard; wearing fins or surf slippers helps avoid such dangers, as well as nasty reef scrapes and coral cuts.