Many types of eels display various behaviors and live in different habitats, though people often overlook them. There are both saltwater and freshwater eel species.
Saltwater eels inhabit the vast expanses of the world's oceans, from the warm tropical reefs teeming with colorful moray eels to the cold, dark depths where the mysterious gulper eels reside. On the other hand, freshwater eels can often be found in rivers, creeks, and even small ponds, with species like the American and European eels making remarkable migrations between these freshwater habitats and the ocean for breeding purposes.
This guide examines their defining characteristics, natural habitats, and eating habits, illuminating the sub-species forming the universe of eels. Before proceeding below, here’s a fun fact: electric eels are not eels at all! Check the explanation in the FAQs at the end.
The types of eels are categorized into two broad orders: Anguilliformes, the true eels, and Saccopharyngiformes, the gulper eels.
Anguilliformes, the larger of the two orders, comprises 20 families with more than 800 species. This group includes some of the most widely recognized eels, like the American and European eels (genus Anguilla), the moray eels (family Muraenidae), and the conger eels (family Congridae).
The Saccopharyngiformes, on the other hand, is a much smaller order consisting of four families and about 30 species. This order is known for its bizarre and exotic members, such as the aptly named gulper eels (family Saccopharyngidae) and the thread-like snipe eels (family Nemichthyidae).
Though these classifications seem straightforward, they result from years of scientific research and analysis. Read on to learn what makes each eel species unique across the 20 featured below.
20 Types of Eels All Over The World
1. American Eel (Anguilla rostrata)
The American Eel lives in the far-flung corners of the North Atlantic. It has a snakelike body and can grow up to five feet, though most individuals measure only two to three feet.
Its skin ranges from yellow to green-brown, and it has a lighter belly, camouflaging it in riverbeds and coastal waters.
These types of eels are both freshwater and saltwater eels. They spend most of their lives in freshwater or brackish environments. However, during the breeding season, they migrate to the ocean.
Additionally, these true eels eat various prey, such as insects, crustaceans, and fish. At night, the American eel emerges from the sand to hunt. They also don’t hesitate to step onto land for food.
2. European Eel (Anguilla anguilla)
The European Eel can grow up to 5 feet long and camouflage itself in its environment. Moreover, they are nocturnal hunters that feed on insects, crustaceans, mollusks, and other small aquatic animals.
Additionally, European Eels are catadromous; they spend most of their lives in freshwater or brackish waters and travel to the Sargasso Sea to breed1.
They turn from larvae to glass eels during their journey, then to yellow and silver eels. These types of eels can also breathe through their skin, enabling them to survive short periods of drought.
3. Japanese Eel (Anguilla japonica)
The Japanese Eel lives off the coast of Japan, Korea, Vietnam, and the northern regions of the South China Sea. They are olive green, tranquil brown, white, or soft yellow. Moreover, they have small heads with large eyes that help them see in the dark.
The Japanese Eel migrates most of its time in freshwater or brackish waters. During the breeding season, they migrate into the ocean, swimming hundreds, or even thousands, of miles to reach spawning grounds in the far West of the North Pacific Ocean.
Part of the eel life cycle is the development of leptocephali, offspring that rely on ocean currents to guide them back to their freshwater habitats for several months3.
4. Indian Longfin Eel (Anguilla bengalensis)
The Indian Longfin Eel inhabits the Indian and Western Pacific Oceans. Measuring 4 feet long, it has an impressive snout and long dorsal and anal fins, hence the name. This solitary animal prefers the quiet depths of the ocean.
The Indian Longfin Eel begins life in the ocean but eventually migrates to freshwater. Once there, it leads a primarily solitary life, emerging at night to feed on crustaceans, mollusks, and fish.
While this eel can live up to 20 years, it takes females between 12 and 20 years to reach sexual maturity, potentially threatening their survival due to human consumption.
5. Indonesian Shortfin Eel (Anguilla bicolor bicolor)
The Indonesian Shortfin Eel is a deep-brown to light-yellow eel that inhabits the Indian Ocean, Western Pacific Ocean, and Indonesian waters. It is a unique subspecies of the Shortfin Eel, characterized by its shorter dorsal fin beyond the pectoral fins. This catadromous eel lives in freshwater rivers and streams.
During the breeding season, these eels swim against the current and return to the ocean. Moreover, the Indonesian Shortfin Eel embarks on land excursions, using its slender body and sharp pectoral fins to explore new territories. They undertake these journeys at night when they emerge from their burrows and crevices.
Scanning their surroundings for prey, they mainly feed on small fish, crustaceans, and other invertebrates.
6. African Longfin Eel (Anguilla mossambica)
The African Longfin Eel lives in the rivers and estuaries of Eastern and Southern Africa. It can grow up to 4 feet long and is one of the world’s largest eels. Moreover, it is a nocturnal creature that hunts crustaceans, fish, and smaller water-dwelling animals.
The African Longfin Eel spends most of its life in freshwater habitats, then embarks on a grand journey to spawn in the ocean. However, the rest of its breeding habits remain a mystery to scientists.
7. Zebra Moray Eel (Gymnomuraena zebra)
The Zebra Moray Eel has a body pattern of alternating black and white stripes. It commonly lives in the coral reefs of the Indo-Pacific region, including the Red Sea, Hawaii, and the eastern coast of Africa. The eel's teeth are shaped like molars, crushing crustaceans such as shrimp, crabs, and mollusks before eating them.
Despite its unique appearance and eating habits, this type of eel is peaceful, retreating to rocky shelters when approached by divers or snorkelers.
8. New Zealand Longfin Eel (Anguilla dieffenbachii)
The freshwater habitats of New Zealand are home to the New Zealand Longfin Eel. These eels can grow up to 6.6 feet long, with females reaching this maximum size. Hence, the New Zealand Longfin Eel is one of the world’s largest eel species.
These eels are olive green to brown. Their long dorsal fins are notable features; they undulate gracefully, helping them move quietly during nocturnal hunts. Despite their size, they are shy creatures.
During the day, they hide in shadowy locations, such as submerged logs or unseen crevices. Their keen sense of smell helps them find prey, primarily invertebrates, small mammals, and other fish.
Moreover, these eels can live for over a century but only breed once. During the breeding season, they embark on an epic journey from their freshwater homes to their spawning grounds in the deep Pacific Ocean near Tonga. After mating, the eels die. Then, thousands of minute larvae return to New Zealand, guided by the waves.
9. Australian Longfin Eel (Anguilla reinhardtii)
The Australian Longfin Eel lives in Australian waters. It resembles a snake, with a long body and a dorsal fin running almost its entire body length. Despite its appearance, this eel is not hostile towards humans unless disturbed.
The Longfin eel has rich brown and green skin that protects against parasites and enables the eel to move effortlessly through water.
Adult Longfins undertake a challenging journey each year to the Coral Sea near New Caledonia to breed thousands of miles away from their freshwater homes. Afterward, their offspring, known as elvers, make the reverse odyssey back to their freshwater origins over several years. These eels can take up to 20 years to reach sexual maturity.
10. Southern Shortfin Eel (Anguilla australis)
The Southern Shortfin Eel typically inhabits cooler freshwater areas in Australia, New Zealand, and Tasmania. This species is dark brown and olive green with a lighter underbelly and a shorter dorsal fin. Moreover, they can briefly go on land due to their snakelike locomotion.
Additionally, the Southern Shortfin Eel starts life in the deep Coral Sea, turning from larvae into transparent glass eels. Braving numerous challenges, these eels journey from their birthplace to freshwater habitats. Female eels are larger than males, growing up to 3.3 feet long.
These types of eels prefer to stay hidden during the day under rocks and vegetation. They are active at night, feeding on fish, crustaceans, insects, and worms.
11. Purple Spaghetti Eel (Moringua raitaborua)
Measuring approximately 17 inches, the Purple Spaghetti Eel has a slender, elongated body that resembles spaghetti. Its head is so small that it blends seamlessly with its body, and its eyes are hidden beneath a layer of skin, making them almost invisible.
Found predominantly in the waters of the Indo-West Pacific, the Purple Spaghetti Eel thrives in freshwater or brackish environments.
12. Snake Eel (Ophichthidae)
Snake eels or worm eels look like snakes with long bodies and a scaled texture. They range in color from brown to bright hues and often have patterns serving as camouflage. They live in marine, brackish, and sometimes freshwater environments and spend most of the day burrowed in sand or mud.
This type of eel has a forward escape technique—they disappear by moving forward, not backward, into the sand. Additionally, their hard, pointed tails are uniquely adapted for burrowing. These traits showcase the fascinating adaptability of life underwater.
13. Pike Conger Eel (Muraenesox bagio)
Pike conger eels can live in fresh and saltwater environments, although they typically prefer saltwater. These eels can grow from two to eight feet long and survive depths of up to 2624.67 ft.
Approximately fifteen different species of pike conger eels live around the world.
14. Sawtooth Eel (Serrivomeridae)
Sawtooth eels are pelagic fish living in the dark depths of the ocean. Their name comes from their inward-facing saw-like teeth. This type of eel comprises around eleven species; most sawtooth eels have a maximum size of 24 to 28 in.
15. Mediterranean Moray Eel (Muraena helena)
Growing up to 5 feet, this long, slender eel moves quickly through the rocky reef environment. The Mediterranean Moray Eel ranges from dark brown to soft grey, with a yellowish underbelly. It doesn't have pectoral fins.
This eel feeds on fish, squids, and octopuses. However, it's far from the top of the food chain as larger fish and marine mammals like seals and sea lions also prey on them.
Moreover, the Mediterranean Moray Eel forces water over its gills to breathe, requiring it to open and close its mouth rhythmically.
16. Giant Moray Eel (Gymnothorax javanicus)
The Giant Moray Eel lives in the Indo-Pacific region's rocky seafloors and coral reefs. It is the world's largest moray eel, measuring 10 feet and weighing over 66 pounds. (The Slender Giant Moray Eel is longer.) Its brown skin has a unique dark spot pattern contrasting with the colorful reefs.
Moreover, this nocturnal eel hides in crevices and caves to avoid predators and rest for its nighttime hunts for fish, cephalopods, and crustaceans.
The Giant Moray Eel also forms alliances with coral groupers to hunt prey. It chases prey into open waters while the grouper takes advantage.
17. California Moray Eel (Gymnothorax mordax)
The California Moray Eel lives in the moonlit kelp forests of the eastern Pacific. Their color palette ranges from bronze to olive green and can grow up to 60 in long, although most average around 24 in. Despite their size, they are shy and spend their days hidden in rocky alcoves, away from other marine life.
At nightfall, the California Moray Eel becomes active and relies on its sense of smell to locate small fish or various invertebrates. It creates a cloud of slime to trap and paralyze its victim against the reef or kelp.
Additionally, the eel starts life as a female and becomes a male as it matures through a phenomenon called protogyny.
The California Moray is a primarily solitary species that mainly interacts with others during mating.
18. Longfin African Conger (Conger cinereus)
The Longfin African conger lives in the Indo-Pacific oceans, from the Red Sea and East Africa to the Marquesas and Easter Islands. They can survive depths of 262 feet, growing up to 4.3 feet long.
This type of eel feeds on small fish and crustaceans. It has an elongated body and fin extending from just behind the head to the tip of the tail, earning it the name 'Longfin.'
19. Snowflake Moray Eel (Echidna nebulosa)
The Snowflake Moray Eel has a distinctive pattern of black splotches resembling snowflakes. It is a relatively small eel, typically up to 24 inches long. They live in the tropical Indo-Pacific region, among coral reefs and rock formations in warm summer waters.
The nocturnal Snowflake Moray Eel spends the day in reef crevices to avoid the sun. It is skilled enough to navigate its underwater labyrinth and hunt for food at night. Moreover, its long, flexible body allows it to probe into narrow corners and crevices, looking for small fish and crustaceans.
The Snowflake Moray Eel is peaceful when not on the hunt, attracting aquarium owners worldwide.
20. Green Moray Eel (Gymnothorax funebris)
The Green Moray Eel inhabits the deep, shadowy waters of the western Atlantic Ocean. Green Moray Eels can grow up to 7.2 feet long and weigh approximately 64 lbs.
Despite its name, this species is not green, but its natural color is soft brown with a layer of yellow mucus. When hit by light, this mucus gives the appearance of vibrant green.
These types of eels periodically open and close their mouths because their gills require a continuous flow of water for breathing. They eat mainly fish, squids, and crabs. Lastly, they hide in dark crevices of coral reefs or rocky underwater terrains during the day, coming out at night to hunt.
FAQs about Types of Eels
There are over 800 known species of eels, from the giant moray to the small garden eel.
Eels inhabit both marine and freshwater environments, often in warmer, tropical waters like coral reefs, rocky coasts, and rivers.
Eels are elongated fish, varied in color, and many have sharp, strong jaws.
No, most eels are harmless. A few, like the electric eel, can be dangerous, but they are not common.
The lifespan and growth rate vary widely among species. However, as a general rule, eels can live between 10 to 20 years.
Despite their name, electric eels are not actually eels. They belong to the knifefish family, which is more closely related to catfish and carp. They have three organs responsible for producing electric discharges2.
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Catania, K. C. (2015). Electric eels concentrate their electric field to induce involuntary fatigue in struggling prey. Current Biology, 25(22), 2889–2898.
Tsukamoto, K., Chow, S., Otake, T., Kurogi, H., Mochioka, N., Miller, M. J., Aoyama, J., Kimura, S., Watanabe, S., Yoshinaga, T., Shinoda, A., Kuroki, M., Oya, M., Watanabe, T., Hata, K., Ijiri, S., Kazeto, Y., Nomura, K., & Tanaka, H. (2011). Oceanic spawning ecology of freshwater eels in the western North Pacific. Nature Communications, 2, 179.