Glossary

Carcharhinus leucas. One of the most dangerous sharks due to its aggression, territorial behavior, and unique ability to survive in both salt and fresh water. Responsible for many attacks in murky coastal and river waters. One of the most testosterone-dense vertebrates measured.

The largest predatory fish on Earth. Responsible for the most recorded unprovoked attacks on humans. Found in cool, coastal waters worldwide. Bite-and-release behavior is common — most victims are not consumed. Endothermic (warm-bodied), allowing sustained high-speed predation.

Second only to the great white in number of recorded attacks. Known for its indiscriminate diet and tendency to patrol shallow coastal reefs. Has the most diverse documented diet of any shark. Common in tropical and subtropical waters.

Historically responsible for mass-casualty incidents at open-ocean shipwrecks and air crashes. Less relevant today due to drastically reduced populations from overfishing. Critically endangered on the IUCN Red List.

Recognizable by the scalloped front edge of its cephalofoil. Forms large daytime schools of hundreds of individuals, one of the few sharks to do so. Feeds primarily on fish and cephalopods. Critically endangered due to the fin trade and bycatch.

The largest hammerhead species. Distinguished from the scalloped hammerhead by a nearly straight cephalofoil front edge and a very tall first dorsal fin. A specialist stingray predator — its electroreception is so precise it can locate rays buried under sand.

The fastest shark species, capable of sustained speeds over 35 km/h with bursts above 70 km/h. Endothermic like the great white. A highly migratory open-ocean predator that targets tuna and billfish. Endangered on the IUCN Red List.

A bottom-dwelling shark common in warm, shallow coastal waters of the Atlantic and Eastern Pacific. Slow-moving and generally non-aggressive, but capable of powerful bites if provoked. A buccal pumper — one of the few sharks that can remain stationary on the seafloor.

The largest fish on Earth. A filter feeder that consumes plankton, small fish, and fish spawn by ram-filtering seawater through its gill rakers. Completely harmless to humans. Aggregates seasonally at predictable feeding sites including Ningaloo Reef (Australia) and the Yucatán (Mexico).

One of the most common sharks on Indo-Pacific and Red Sea coral reefs. Easily identified by the distinctive black tips on its fins. Often found in very shallow water — sometimes less than 30cm deep. Responsible for a number of minor 'bite' incidents in wading swimmers.

Named for its yellowish-brown coloring, which provides camouflage against sandy seafloors. Common in shallow subtropical waters of the Atlantic and Eastern Pacific. One of the most-studied sharks in captivity and in the field — used extensively in behavioral and sensory research.

Known as grey nurse shark in Australia. Despite its fearsome appearance — it constantly displays its teeth — it is one of the least aggressive large sharks. The only shark known to gulp air at the surface to achieve neutral buoyancy. Near threatened globally; critically endangered in parts of its range.

Also called copper shark. The only predominantly temperate-water member of the Carcharhinus genus. Forms large seasonal aggregations off the coasts of South Africa, Australia, and New Zealand, often associated with sardine and yellowtail migrations. Involved in several incidents in South Africa.

The most wide-ranging shark in the world, found from polar to tropical seas. Slender and built for sustained open-ocean cruising. The most heavily fished shark species globally — estimated at tens of millions of individuals killed annually as bycatch in tuna and swordfish longline fisheries.

A genus of highly camouflaged, bottom-dwelling sharks native to shallow Indo-Pacific coastal waters. Uses elaborate skin flaps and mottled patterns to ambush prey. Responsible for a small number of incidents, almost always when inadvertently stepped on or harassed. Orectolobiform (carpet shark order).

Named for its smooth, silky skin texture. One of the most abundant large oceanic sharks, often found around offshore seamounts and fish aggregating devices. Forms large feeding aggregations. Highly vulnerable to bycatch in tropical tuna fisheries.

The ability to detect weak electrical fields generated by the muscle movements and nerve impulses of prey. Sharks use specialized jelly-filled organs called ampullae of Lorenzini, concentrated around the snout. Effective in murky water at close range — typically within 1 metre. Hammerheads have an unusually wide distribution of these organs across their cephalofoil.

A sensory system running along each flank of the shark's body, consisting of fluid-filled canals with hair cells (neuromasts). Detects low-frequency pressure waves and water movement — enabling sharks to sense struggling prey, approaching objects, and changes in current at longer ranges than electroreception allows.

Placoid scales covering the skin of sharks, structured like tiny teeth (with enamel, dentine, and a pulp cavity). Oriented to reduce turbulence as water flows over the body, decreasing drag by up to 12% compared to a smooth surface. Swimwear and marine engineering have both drawn on this structure for design inspiration.

A camouflage strategy in which the animal is darker on its dorsal (upper) side and lighter on its ventral (lower) side. When viewed from above, the dark back blends with deeper water; when viewed from below, the pale belly blends with the sky-lit surface. Highly effective in the open ocean and employed by the majority of shark species.

A translucent third eyelid present in many shark species — including the great white and bull shark — that rolls over the eye during a bite to protect it from the prey's thrashing. Great whites lack this structure and instead roll their eyes backward for protection.

The physiological process by which animals maintain the chemical balance of their internal fluids. Most sharks are osmoconformers in salt water, maintaining internal urea concentrations close to their environment. Bull sharks are exceptional: they can actively regulate their kidney function to excrete more dilute urine in low-salinity environments, enabling survival in freshwater rivers and lakes.

A breathing strategy in which the shark must continuously swim with its mouth open to force water over its gills. Great whites, makos, and whale sharks are obligate ram ventilators — they suffocate if they stop swimming. In contrast, nurse sharks and wobbegongs are buccal pumpers that can actively pump water over their gills while stationary.

Sharks reproduce via three main strategies. Oviparous species (e.g. catsharks, horn sharks) lay egg cases ('mermaid's purses'). Ovoviviparous species (e.g. great whites, whale sharks) retain eggs internally, with embryos feeding on yolk or other eggs (oophagy). Viviparous species (e.g. bull sharks, lemon sharks) develop a placental connection to the mother, resembling mammalian pregnancy.

An attack pattern in which a shark makes one or more investigative passes — sometimes bumping the target with its snout — before biting. More common with bull and tiger sharks than great whites. Suggests deliberate evaluation of prey suitability rather than pure ambush predation.

An exploratory bite used by sharks — particularly great whites — to assess whether an unfamiliar object is edible. Since sharks lack hands, the mouth is the primary investigation tool. Many great white incidents are attributed to test bites, after which the shark disengages upon finding the target is not preferred prey.

A highly agitated competitive feeding state triggered by high prey density, blood, or thrashing in the water. Multiple sharks compete rapidly for food, losing the caution they typically display. Largely a media term — documented frenzies in research contexts are rare compared to normal foraging behavior.

A predatory strategy in which a shark accelerates vertically from depth and launches out of the water — typically targeting seals at the surface. Best documented in great whites at Seal Island, False Bay, South Africa. Breaches can reach 3–4 metres above the water surface and are executed at speeds approaching 40 km/h.

An incident in which a shark bites a live human where the human had not initiated the encounter through direct provocation. The GSAF's primary classification for most recorded incidents. Includes test bites, mistaken identity, and territorial responses.

An incident where the human initiated physical contact with the shark, such as touching, feeding, spearing, or accidentally stepping on it. These incidents are tracked separately and typically reflect lower aggression — the shark is responding defensively rather than as a predator.

The most common attack pattern — a single rapid bite followed by retreat, typically in turbid surf zones. Usually attributed to mistaken identity, where the shark briefly investigates an unfamiliar object and disengages quickly. Injuries are often lacerations rather than deep tissue damage. Surfers and swimmers in murky shorebreak are the most common victims.

Global Shark Attack File. A long-running research initiative maintained by the Shark Research Institute in Princeton, New Jersey, that documents shark-human interactions worldwide. Maintains one of the most comprehensive incident databases in existence, dating back to 1580.

A water sport involving a handheld inflatable wing and a hydrofoil board that lifts the rider above the water surface. A rapidly growing activity that has appeared in recent shark incident reports, particularly in Australia. Practitioners typically cover more ocean area per session than surfers, increasing statistical proximity to sharks.