Dolphins are intelligent marine mammals widely recognized for their playful and gentle demeanor. Often portrayed as friendly creatures, this perception leads to questions about their interactions with humans and whether these encounters can turn aggressive.
Do Dolphins Attack Humans?
While dolphins are generally perceived as benign, aggressive incidents towards humans do occur, though rarely. These are not predatory attacks, as humans are not part of their natural diet. Aggressive actions can involve pushing, biting, or ramming, resulting in injuries from minor bruises to serious wounds, including broken bones. Globally, approximately 50 confirmed reports of dolphins targeting humans were recorded between 1990 and 2020. The International Shark Attack File (ISAF) reports 2-3 unprovoked dolphin incidents annually, a number substantially lower than annual shark attacks.
Documented cases highlight this potential for harm. In Brazil, a dolphin named Tião was associated with multiple injuries and a fatality after being provoked by humans. More recently, a single male dolphin in Japan has been linked to numerous injuries, including broken bones, sustained by swimmers. These incidents underscore that while most human-dolphin interactions are peaceful, dolphins, as powerful wild animals, are capable of causing injury under specific circumstances.
Understanding the Causes of Aggression
Dolphins may exhibit aggression for several reasons, often stemming from natural instincts or human-induced factors. One cause is defense, where dolphins protect their offspring or territory from perceived threats. Mother dolphins are fiercely protective of their calves and may attack if they sense danger. Dolphins also defend their feeding or mating territories against intruders.
Stress or provocation from human interaction can trigger aggression. Harassment such as chasing, touching, or feeding wild dolphins can alter their natural behavior and lead to frustration. In captive environments, limited space, unnatural social groupings, and constant human presence can induce chronic stress, leading to aggressive outbursts towards other dolphins or handlers.
Misinterpretation of human actions can also play a role in aggressive encounters. Dolphin play can be rough, involving behaviors like biting, ramming, and chasing, which can be misconstrued as aggression due to the dolphins’ size and strength. What a dolphin considers a normal social interaction within its species might be perceived as an attack by a human.
Hormonal factors can also influence aggression, particularly in male dolphins during mating season. Male dolphins can exhibit sexual aggression, dominance assertion, and even infanticide within their pods, and this behavior can sometimes be misdirected towards humans.
Safe Interactions with Dolphins
Interacting with dolphins safely requires respecting their wild nature and maintaining appropriate boundaries. Keep a respectful distance from wild dolphins, typically at least 50 yards (150 feet). This distance helps prevent disturbing their natural behaviors such as feeding, nursing, or resting. If dolphins approach your vessel, maintain your course or put the engine in neutral to avoid startling them.
Feeding wild dolphins is illegal and harmful to their well-being. It habituates them to human presence, causing them to lose their natural wariness and become dependent on handouts, which can lead to abnormal foraging strategies and social behaviors. This dependency increases their risk of injury from boat propellers or entanglement in fishing gear. Human food can also be unhealthy for dolphins and may transmit diseases.
Avoid swimming with wild dolphins unless part of a supervised and ethical tour. Never attempt to touch, pet, or harass dolphins, even if they approach closely. Touching can transmit diseases and is illegal in many regions. Observing their behavior for signs of discomfort, such as tail slapping, rapid changes in direction, or loud breathing, indicates they are stressed and need space. Ensuring calm and minimal movements helps prevent startling them, allowing for a safe and respectful viewing experience.