Eels can bite or deliver a shock if they feel threatened or are provoked. While such encounters are uncommon, most incidents occur due to defensive reactions or accidental contact. Understanding the specific circumstances and types of eels involved helps clarify this behavior.
Eel Species and Biting Behavior
Moray Eels
Moray eels are among the most recognized species known for their biting capabilities. They are typically found in tropical and temperate marine environments, often hiding in rocky crevices or coral reefs. Moray eels are not inherently aggressive; however, they may bite defensively if disturbed or threatened. Bites can also occur if humans attempt to feed or handle them, as their poor eyesight might lead them to mistake a hand for food.
Electric Eels
Electric eels, a type of knifefish, inhabit freshwater environments in South America. They generate powerful electric shocks for defense and hunting, rather than biting. While they do not intentionally attack humans, accidental contact can result in a shock if one inadvertently steps on or disturbs them. A single jolt can range from painful muscle contractions to temporary paralysis, and multiple shocks can pose a serious risk.
Freshwater Eels
Freshwater eels, such as those found in North America, are generally timid and prefer to avoid human interaction. They typically flee rather than fight when accosted. Bites from freshwater eels are exceedingly rare, occurring only if directly provoked or if the eel feels cornered.
Characteristics of an Eel Bite
Moray Eel Bite Characteristics
A moray eel bite can be notably painful and result in extensive bleeding. Their mouths feature sharp, backward-pointing teeth designed to prevent prey escape. Moray eels also possess a second set of jaws, called pharyngeal jaws, located in their throat, which help them grip and pull prey deeper. Injuries can include puncture wounds, cuts, gashes, and deep lacerations, with severity depending on the eel’s size.
Moray eel bites carry a risk of infection from bacteria in the eel’s mouth, such as Vibrio and Pseudomonas species. Some moray eels also have toxins in their mouth mucus and body slime, including hemagglutinin and crinotoxins, which can contribute to pain and heavy bleeding by causing red blood cells to clump or destroying them. While these toxins can intensify symptoms, moray eels are not venomous like snakes, meaning they do not inject venom through hollow teeth.
Electric Eel Shock Characteristics
An electric eel’s defensive action involves delivering a powerful electric discharge rather than a bite. These shocks can reach up to 600-860 volts, causing intense pain, muscle spasms, and temporary paralysis. While a single shock is rarely fatal to healthy adults, the primary danger lies in indirect consequences, such as incapacitation leading to drowning. Multiple shocks can also lead to respiratory or heart failure.
Minimizing Risk and Responding to an Encounter
Minimizing Risk
To minimize the risk of an eel bite or electric shock, exercise caution and respect their natural behavior. Avoid provoking eels, such as attempting to touch or hand-feed them in their natural habitats or aquariums. When in waters where eels might be present, like coral reefs or rocky areas, avoid placing hands or feet into crevices where eels might hide. Divers and snorkelers should maintain a safe distance and avoid sudden movements that could startle an eel.
Responding to a Bite
If an eel bite occurs, immediate first aid is necessary. Move away from the eel and the water. For moray eel bites, wash the wound thoroughly with soap and water. Apply pressure to stop bleeding and cover the wound with a clean, sterile dressing. Seek prompt medical attention; a doctor can assess the wound, remove any broken teeth, and determine if antibiotics or a tetanus shot are needed to prevent infection.
Responding to a Shock
In the event of an electric eel shock, exit the water safely. While direct fatalities are rare, the shock can cause disorientation or temporary paralysis, increasing the risk of drowning. Seek medical attention to monitor for any delayed effects, such as muscle damage or cardiac irregularities.