Shark reactions to scuba divers in two marine protected areas of the Eastern Tropical Pacific

Shark reactions to scuba divers vary significantly based on diver behavior, observation strategy, and proximity. This study found that sharks exhibit stronger behavioral responses when divers employ 'direct approach,' sudden movements, or move closer than 4 meters. These actions, along with the use of camera flashes and noise, tend to elicit evasion or alert reactions in sharks, particularly those species targeted by divers. Interestingly, divers are more intrusive towards species they perceive as less threatening and easier to access due to environmental conditions. The research, conducted in two marine protected areas—Galápagos Marine Reserve (Ecuador) and Malpelo Fauna and Flora Sanctuary (Colombia)—analyzed five shark species using four reaction categories and five diver behavior categories. It highlights the need for responsible diving practices to minimize impacts on shark behavior and ecology.

Cubero‐Pardo, P., Herrón, P., & González‐Pérez, F. (2011). Shark reactions to scuba divers in two marine protected areas of the Eastern Tropical Pacific. Aquatic Conservation: Marine and Freshwater Ecosystems, 21(3), 239–246. Portico. https://doi.org/10.1002/aqc.1189