Ocean areas where the risk of human-shark interaction is notably higher than the global average are often described as “shark-infested waters.” Scientists identify these hotspots using reliable data regarding the frequency of documented unprovoked incidents. This data-driven approach focuses on regional risk rather than the misleading term “infestation.”
Defining Shark Activity Hotspots
The determination of a shark activity hotspot relies heavily on global databases that systematically track and categorize every reported human-shark encounter. The most recognized is the International Shark Attack File (ISAF), maintained by the Florida Museum of Natural History. The ISAF distinguishes between “unprovoked” and “provoked” incidents, with unprovoked bites being the standard metric for risk assessment. An unprovoked bite occurs in the shark’s natural habitat without any human initiation, such as harassing the animal or attempting to feed it.
Hotspots are regions with consistently high numbers of unprovoked bites over a multi-year period. This metric provides a clearer picture of where human and shark paths most frequently and unintentionally cross. Analyzing these incidents allows researchers to understand the circumstances and species most often involved, reflecting a specific confluence of environmental and human factors.
Global Regions with the Highest Documented Interactions
The United States consistently records the highest annual number of unprovoked shark bites globally. Within the U.S., Florida is the primary location for these incidents. Volusia County, particularly New Smyrna Beach, frequently earns the nickname “Shark Bite Capital of the World.” The majority of these Florida incidents are typically non-fatal “hit-and-run” bites attributed to smaller species like the Blacktip and Spinner sharks.
Australia is another major global hotspot, generally ranking second in total bites but often exhibiting a higher rate of fatalities. The states of New South Wales, Western Australia, and Queensland are the most active coastal areas for interactions. The species responsible for the majority of serious incidents are the Great White, Tiger, and Bull sharks, known for their size and feeding behavior.
South Africa is historically recognized for a high rate of severe unprovoked attacks, particularly off the Eastern and Western Cape provinces. The region’s temperate waters are home to a concentration of larger predatory species, including the Great White shark. While South Africa’s total number of bites is lower than the U.S. or Australia, its fatality rate has been notably higher historically.
Ecological Drivers of Shark Concentration
Coastal zones become hotspots due to a specific combination of ecological and environmental factors that attract sharks. Many of these areas are shallow, highly productive regions that serve as crucial nursery grounds for juvenile sharks, such as the Blacktip sharks off the Florida coast. Abiotic factors, including water temperature, salinity, and depth, play a significant role in determining species distribution and movement patterns.
The presence of abundant prey is a primary driver, causing sharks to congregate near concentrated food sources like seal colonies or large schools of baitfish. Coastal areas near deep oceanic drop-offs, such as those in Australia and South Africa, also create natural corridors for large, migratory species like the Great White shark. Human activities further complicate this dynamic, as fishing, the use of certain bait, and sewage runoff can inadvertently draw sharks closer to popular swimming and surfing areas.