Yes, shiny or highly reflective swimsuits and jewelry can attract sharks. While sharks are generally colorblind, they have acute vision for contrast and brightness, and the reflected light from metallic or shiny, bright materials can resemble the sheen of fish scales, which are a primary food source for many sharks.
Don't swim/surf/dive near harbor entrances, river mouths and channels, especially after heavy rains. These types of waters are known to be frequented by sharks. Don't wear high-contrast swimwear or shiny jewelry. Sharks can see contrast well.
To tell if a shark is near, watch for nature's signs like diving birds or agitated fish, notice unusual shadows or fins, and be aware of areas with fishing activity, but most importantly, listen to lifeguard warnings, avoid murky water, and observe sharks' behavior for signs of excitement or erratic movements, indicating you should calmly leave the water.
Results are mostly inconclusive, but some general principles have been advanced: Sound: Sound, rather than sight or smell, seems to be a shark's primary cue for moving into an area. Certain types of irregular sounds—like those made by a swimmer in trouble or a damaged fish—seem to attract sharks from great distances.
Alternatively, divers and swimmers can probably reduce the chance of an interaction with a shark by avoiding bright and highly contrasting swimwear or dive gear. We personally prefer to use dark blue or black fins, mask, tank, and wetsuit while diving.
It has traditionally been believed that sharks are repelled by the smell of a dead shark. However, modern research has had mixed results. Semiochemicals have shown some efficacy at getting sharks to leave a feeding area for a few minutes.
Don't wear shiny objects like necklaces, earrings or watches. The glint from metal jewelry may resemble a fish or their scales, and attract curious sharks. Don't splash or make erratic motions that might alert a shark.
Instead of swimming away: stand your ground, face the shark, make eye contact, extend your fins out if you can to ask for space, and if you absolutely need to then push firmly down on the top of the shark's head to guide them away from you, making sure to follow through as they swim away.
Sharks are generally most active during low-light periods, specifically dawn, dusk, and night, as these times offer them a hunting advantage with reduced visibility, though activity varies by species and location. While many species are crepuscular (active at twilight), some, like reef sharks, hunt all day, and pelagic species roam widely, so it's crucial to understand local conditions, as increased human presence also influences when "attacks" occur.
A: It is believed that shiny jewelry, sparkly jewels, glittery nail polish, and other highly light reflective items attract sharks. They will not see such items from far away and come charging in, but they might come to inspect it and find out what you are.
Shark repellent refers to methods or devices designed to keep sharks away from an area, using magnetic fields, electric pulses, or strong smells (like dead shark extract) to disrupt their senses, with Sharkbanz (magnets) and electric deterrents (like RPELA) being popular personal options, while in business, "shark repellent" also means tactics companies use to fend off hostile takeovers, like golden parachutes. Both marine and business applications aim to deter unwanted approaches, though effectiveness varies and is often debated.
If a shark charges, fight back
“That happens nine times out of 10.” If that does not work, and a shark tries to bite a swimmer—or even has a limb in its mouth—Naylor says the best course of action is to poke the shark hard in the eyes.
Sharks see in contrast and not in a full color spectrum, so these higher contrast colors like whites and yellows will typically get more attention from the sharks. Often things that are small and white or yellow are things that would be seen as prey to the sharks.
Olympic swimmers stopped wearing traditional Speedo briefs for performance reasons, switching to high-tech, full-body "super suits" in the late 2000s to reduce drag, but these were banned by 2010, leading to today's textile "jammers" (mid-thigh suits) that offer less drag than briefs, provide compression, and adhere to World Aquatics' rules for a fairer competition.
Nearshore areas provide a safer environment for their young, away from larger predators found in deeper waters. In fact, a 2024 study found that juvenile white sharks tend to gather within 1 km (0.62 miles) off the southern California coast at depths of less than 10 meters (32.8 feet).
To tell if a shark is near, watch for nature's signs like diving birds or agitated fish, notice unusual shadows or fins, and be aware of areas with fishing activity, but most importantly, listen to lifeguard warnings, avoid murky water, and observe sharks' behavior for signs of excitement or erratic movements, indicating you should calmly leave the water.
White shark attacks upon humans typically occur nearshore in water 10-30 feet deep. The majority of attacks occur at the surface, placing swimmers, surfers, kayakers, and scuba divers (when at the surface) at greatest risk.
Bump-and-bite attack – the shark circles and bumps the victim before biting. Great whites are known to do this on occasion, referred to as a "test bite", in which the great white is trying to identify what is being bitten.
Shark repellent bracelets offer limited, short-range protection, primarily reducing the risk of minor "investigative" bites from smaller sharks, but they are not foolproof and don't reliably deter large, predatory sharks like Great Whites, with some products showing little scientific backing while others (like the electric Ocean Guardian) prove somewhat effective in close proximity. They work by disrupting sharks' electroreceptors, but effectiveness varies by brand, technology (magnetic vs. electric), and shark species, acting as a risk reducer, not a guarantee.
So stay calm, avoid splashing and stand upright in the water (fins down, head up) and face the shark head on, making eye contact if you can. This will make you look less like a prey animal, and seem larger and more intimidating to the shark. Then calmly make your way out of the water as soon as you can.
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While sharks can smell human blood, they are more interested in sniffing out what's for dinner: other fish, crustaceans, and molluscs. Ocean currents also play a role in how far a scent can travel.
The ocean absorbs red colors first, erasing them at 15 feet depth. Children in high-visibility suits receive attention 3x faster. Lifeguards scan for bright colors when monitoring swimmers.