If a shark is attacking you, strike it hard in the snout, eyes, or gills. These are the most sensitive areas on a shark’s body, and a forceful hit can interrupt an attack long enough for you to escape. But surviving a shark encounter depends on more than just throwing punches underwater. Knowing how to read a shark’s behavior beforehand, fight effectively during contact, and control bleeding afterward can make the difference between life and death.
That said, your odds of ever needing this advice are extremely low. In 2025, there were 65 confirmed unprovoked shark bites worldwide, with nine fatalities. You are far more likely to drown than to be bitten by a shark. But if you spend time in the ocean, knowing what to do is worth the few minutes it takes to learn.
Recognize Pre-Attack Warning Signs
Sharks don’t always strike without warning. Grey reef sharks, one of the species most commonly involved in encounters with divers, perform a distinct threat display before attacking. The shark raises its snout, drops its pectoral fins downward, arches its back, and holds its tail to one side. It may also swim in exaggerated, side-to-side figure-eight patterns. This posture signals the animal is deciding between attacking and fleeing.
Other species show similar patterns. Silvertip sharks display a visible body shiver along with pectoral fin depression and an overall increase in muscle tension. Across all species studied, the common warning signs are the same: fins pressed downward, exaggerated swimming movements, and a visibly tense body. If you see this behavior, the shark feels cornered or provoked. Back away slowly while keeping the shark in your line of sight. Do not turn your back or splash frantically, both of which can trigger a strike.
Where and How to Strike
If a shark makes contact, your goal is to convince it that you are not worth the effort. Sharks are predators of opportunity, and most bites on humans are investigatory. The shark is trying to figure out what you are. A painful response from you can end the encounter quickly.
Target three areas:
- Snout: The tip of a shark’s nose is packed with sensory organs called ampullae of Lorenzini, small gel-filled chambers lined with nerve cells that detect the faint electrical impulses generated by nearby animals. A hard strike to the snout overwhelms these sensors and can cause the shark to break off.
- Eyes: Gouge, poke, or claw at the eyes. This is the most reliably painful target and forces the shark to protect itself.
- Gills: The gill slits on either side of the head are soft tissue with no cartilage protection. Raking your fingers or a hard object across them causes real discomfort.
Use whatever you have: a camera, a dive knife, a rock, the heel of your hand. A fist alone loses much of its force underwater, so an open palm strike or a rigid object works better. Hit as hard as you can and keep hitting. Do not play dead. Sharks are not bears. Passivity invites continued biting.
What to Do During a Bite
If the shark has you in its jaws, shift from striking the snout to attacking the eyes and gills directly. These are close enough to reach even when the shark has clamped down. Jam your fingers into the eye socket or dig into the gill tissue. The pain response in these areas is strong enough to trigger a release.
If the shark releases and circles back, face it and maintain eye contact. Keep your back to a reef, rock wall, or your dive buddy so the shark cannot approach from behind. Move steadily toward shore, a boat, or any structure you can climb onto. Avoid large, panicked splashing on the surface, which mimics the movements of injured prey.
Immediate First Aid After a Bite
Shark bites kill through blood loss, and it can happen fast. A person with a major bleed can die within five to ten minutes without intervention. Once you or someone nearby is out of the water, stopping the bleeding is the single most important thing you can do.
If you have a commercial tourniquet (the kind found in trauma or first aid kits), place it two to three inches above the wound, avoiding any joints. Tighten it as much as possible. If you don’t have a tourniquet, pack the wound tightly with clean cloth, gauze, or bandages, and press down hard with both hands until emergency services arrive. Avoid using towels to pack the wound, as the fibers can complicate treatment later.
Keep the injured person warm with blankets or towels draped over them, since shock from blood loss drops body temperature rapidly. If the person feels faint or starts losing consciousness, roll them onto their side to keep their airway open.
Infection Risk From Shark Bites
Even a survivable bite carries a serious infection risk. Researchers who cultured bacteria from great white shark teeth identified 24 different bacterial strains, dominated by several species of Vibrio, a group of marine bacteria that thrive in saltwater. These organisms are naturally resistant to common antibiotics like penicillin and amoxicillin, which means standard wound care won’t necessarily prevent infection. Any shark bite, no matter how minor it looks, needs professional medical evaluation and likely a targeted antibiotic course along with tetanus prevention.
Reducing Your Risk Before It Starts
Most shark encounters are preventable. Sharks hunt using a combination of electrical sensing, smell (they can detect blood at concentrations as low as one part per million), and visual contrast. You can reduce your profile as a target with a few straightforward habits.
Avoid swimming at dawn, dusk, or night, when many shark species actively feed. Stay out of the water if you have an open wound. Don’t swim near fishing activity, bait, or schools of fish. Avoid wearing high-contrast clothing or shiny jewelry, which can mimic the flash of fish scales. Swim in groups rather than alone, and stay in areas where you can see the bottom clearly.
Do Electronic Deterrents Work?
Several personal shark deterrent devices are now sold to surfers and divers, but their effectiveness varies dramatically. A study by Flinders University tested five commercial products against white sharks. The best performer, the Ocean Guardian Freedom+ Surf, an electrical device, reduced shark interactions by 56%. But it still failed to deter sharks in 40% of trials. Magnetic deterrent bracelets like the SharkBanz reduced interactions by only 6 to 10%. Wax-based deterrents performed similarly poorly at 14%. No device on the market provides guaranteed protection, so treat them as one layer of risk reduction, not a substitute for situational awareness.
Why Sharks Bite (and Why They Usually Stop)
The vast majority of shark bites on humans are cases of mistaken identity or investigation. A surfer paddling on a board, seen from below against bright sky, looks remarkably like a seal or sea turtle. The shark bites once, realizes you’re not food, and leaves. This is why most shark bite victims survive with a single wound rather than being consumed. Understanding this changes the psychology of an encounter: you are not fighting for your life against a committed predator. You are convincing an animal to give up on a test bite. That is a fight you can win.