Eels are elongated aquatic creatures that inhabit diverse environments across the globe. These fascinating animals are primarily carnivorous predators, meaning their diet is composed almost entirely of other animals. The specific types of prey they consume are varied and often depend on the particular species of eel and its surrounding habitat.
Common Foods Eels Consume
Eels typically feed on a range of smaller aquatic organisms available in their environment. Their diet frequently includes small fish, which are often a preferred food source. Crustaceans (such as crabs, shrimp, and crayfish) and mollusks (including clams and other bivalves) are also common prey items. Worms, such as earthworms and bloodworms, along with various insect larvae, are regularly consumed, especially by freshwater eels. Some eels are also known to eat sea urchins, frogs, and even other eels.
Dietary Differences Among Eels
Species Differences
Eel diets vary significantly by species. Freshwater eels, like the American eel, tend to consume more aquatic insect larvae and crayfish. In contrast, marine eels have access to a broader selection of prey found in saltwater environments.
Developmental Stage
The diet also changes as an eel grows. Larval eels, known as leptocephali, feed on microscopic detrital particles. As they mature into glass eels and elvers, their diet shifts to small crustaceans, worms, and aquatic insects. Larger adult eels typically prey on bigger organisms, with some species becoming primarily piscivorous, focusing on fish. However, adult silver eels, which are preparing for migration to spawning grounds, cease feeding entirely as their digestive systems degenerate.
Habitat Influence
Habitat also influences food choices; eels in freshwater might consume more terrestrial insects, while those in marine settings will eat a wider variety of marine invertebrates. Their diet can adapt to seasonal changes and the immediate availability of prey.
How Eels Hunt and Feed
Hunting Strategies
Most eels are nocturnal hunters. They rely on highly developed senses to locate prey. A keen sense of smell is particularly important for finding food, allowing them to detect chemical cues from potential meals. Many eel species are ambush predators, hiding in crevices, mud, or among rocks, waiting for unsuspecting prey. Moray eels, for example, are known for their effective ambush strategies.
Electric Eels
Other eels, like electric eels, employ unique hunting methods involving bioelectricity. They can emit low-voltage pulses to sense their surroundings and detect hidden prey. Upon detection, they deliver rapid electric pulses that cause fish to twitch, revealing their location. Powerful, high-voltage shocks then paralyze or stun prey, making capture easier. Some electric eels even exhibit cooperative hunting, working in groups to herd and shock fish.
Physical Adaptations
Eels possess physical adaptations that aid their feeding. Their slender, snake-like bodies allow them to navigate tight spaces and burrow into sediment. Many have powerful jaws and sharp teeth for grasping and holding catches. Gulper eels, which inhabit deep-sea environments, are notable for their exceptionally large mouths with unhinged jaws, enabling them to swallow prey larger than themselves. These deep-sea eels may also use bioluminescent tail tips to lure prey.