American conger (eel)
The American conger is a large marine eel found along the continental shelf from Cape Cod to South America, inhabiting depths of up to 850 feet (255 meters). Characterized by its blue-gray or brown-gray skin and a white underbelly, this eel can reach lengths of up to eight feet (2.5 meters) and typically weighs around 22 pounds (10 kilograms). Unlike many fish, American congers lack scales and possess large pectoral fins but no pelvic fins. They are nocturnal hunters, preying on fish, shrimp, and small shellfish, using their sharp teeth to catch meals.
American congers are known for their ability to camouflage by slightly changing their body color to match their surroundings. While they typically face few natural predators, human activities pose the greatest threat to their populations. When it comes time to spawn, adult females migrate to deeper waters offshore from the West Indies, where they lay eggs before dying. These eggs hatch into larval forms called leptocephali, which undergo a metamorphosis into their adult eel shape over time. The lifespan of the American conger ranges from five to 40 years, with their life spent entirely in the western Atlantic Ocean.
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American conger (eel)
The American conger is a large eel, which lives in waters up to 850 feet (255 meters) deep, where it hunts for fish, shrimp, and small shellfish. Conger is from the Latin word meaning sea- eel.
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Anguilliformes
Family: Congridae
Genus: Conger
Species: Oceanica
The American conger is a marine fish that lives along the continental shelf from Cape Cod to South America. The continental shelf is the edge of the continent that lies under relatively shallow water. Beyond the edge of the shelf the bottom drops suddenly into the deeper waters of the ocean. This species of eel lives in the water between the shore and up to 142 fathoms, or 850 feet (255 meters), although it most often swims in waters between 42 and 75 fathoms, or 250 and 450 feet (75 to 135 meters) deep.
The American conger does not have scales on its body. Its skin is usually blue-gray or brown-gray in color, with white on its underbelly. Like its relative, the conger, it has large pectoral fins behind its head but no pelvic fins in the middle of its belly. On average, the length of an American conger is up to five feet (1 1/2 meters), but some have reportedly reached seven or eight feet (2 to 2 1/2 meters). Most weigh up to 22 pounds (10 kilograms).
As it swims with a powerful side-to-side motion, the dorsal fin (back) waves back and forth along the length of nearly its entire body. It moves quickly and smoothly to catch shrimp, small shellfish, and fish, such as butterfish, herring, and other eels. It has a large mouth with many sharp teeth, which become active when it notices prey. It hunts during the night and rests in caves and crevices during the day. The American conger's body color may change slightly depending on the color of its surroundings. This provides some camouflage for the eel, although it does not have known enemies and humans are their greatest threat.
When adult females are ready to spawnor lay eggsit is thought that they migrate to deep waters offshore from the West Indies. After spawning, the adult males and females die, and the eggs are left to hatch on their own. Each of the millions of baby eels hatches from its egg into a larvalor non-adultform called a leptocephalus. A leptocephalus does not look like a miniature eel, but looks like a small, slender, clear willow leaf which is around three to five inches (7 to 13 centimeters) long.
As the leptocephalus grows, it begins to look more like an adult eel. Its body becomes more slender and worm-like and is no longer transparent, or clear. This change, or metamorphosis, from leptocephalus to adult form does not happen right away. It may occur after the baby eel is one or more years old but then happens quickly.
All eel species spawn and produce leptocephali in a similar manner. The leptocephali of other eel species, such as the American and European freshwater eels, may take one to two years to metamorphose as they swim from the western Atlantic Ocean to freshwater on the continents. The American conger eel remains in the western Atlantic Ocean for its entire life. They can live as short as five years and as long as 40.
Bibliography
Segal, Dayva. “American Eel.” AZ Animals, 3 Oct. 2022, a-z-animals.com/animals/american-eel/. Accessed 18 Mar. 2024.