Garden eel
Garden eels are fascinating marine creatures that inhabit sandy bottoms of the Indian and Pacific Oceans. They are named for their appearance, as their slender bodies resemble plants or grass sprouting from the ocean floor. Typically found in clear, shallow waters, garden eels thrive in moderate currents where they can feed on plankton. These eels live in colonies that can comprise thousands of individuals, with each eel using its fleshy tail to burrow into the sand, often remaining hidden except during feeding or mating. Most species grow to around 24 inches long, with some reaching up to 47 inches.
Garden eels generally remain in their burrows for much of their lives, only emerging occasionally for reproduction, which primarily occurs at night. After mating, female garden eels lay eggs, but the young eels are independent from birth and must find their own colonies as they grow. Although they face predation from skates and rays, they can evade capture by quickly retreating into their burrows. Remarkably, garden eels can live for 35 to 40 years, and none of the species are currently considered threatened, showcasing their resilience in their marine environments.
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Garden eel
Garden eels can be found throughout the world's oceans although they often live in the Indian and Pacific Oceans. Poking from their burrows in the sand on the water's bottom are the many species of garden eels. They received their name because the colony of slender-bodied eels looks like a garden of grass or plants. In the morning, they feed on the plankton floating on the currents and then take a nap before feeding again during the afternoon.
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Anguilliformes
Family: Congridae
Genus: Gorgasia and Heteroconger
Species: Various (see below)
There are several species of garden eel in the two genera of the subfamily Heterocongrinae in the Congridae family. Clear, shallow, tropical water flowing at a moderate pace over sandy bottoms and a steady supply of plankton provides a good site for a colony of garden eels. These eels live most often at depths of two to 22 fathoms, or 12 to 130 feet (three to 40 meters). Those of the species Heteroconger halis may live as deep as 33 fathoms, or 200 feet (60 meters). Clear water is best so that they can see their food, tiny creatures called plankton, floating on the currents past their mouths. The eels live in colonies, spaced about 1 1/2 feet (45 centimeters) apart, and a single colony possibly may contain thousands of eels.
Most of these garden eel species grow to be around 24 inches (60 centimeters) long. Some species can grow up to 47 inches (120 centimeters). Heterconger halis is a little shorter and may be up to 20 inches (50 centimeters) long. All of them have very slender bodies and tiny heads, looking very much like plant stems growing from the sand. The species which lives near the Philippine Islands is sometimes called the ribbon eel. All species have hard, fleshy tips at the ends of their tails which help them burrow tailfirst quickly and easily into the sand. Their bodies then secrete, or release through their skin pores, mucus which acts like cement to keep the burrows from collapsing. They do not appear ever to leave their burrows except for rare occasions when mating.
Among the Red Sea species, when a male is ready to mate, he stretches toward a nearby female and ripples his tiny fins at her. If she is also ready, she stretches to meet him, and the two wrap their bodies around each other. They then mate and spawn, or lay eggs. On occasion, a male may leave his burrow and move closer to a female and dig a new burrow, but he then returns to his first burrow after mating. Mating appears to take place at night.
The baby eels do not receive care from the parents. They live together in a group until they are about 10 inches (25 centimeters) long. They then search for an adult colony to join, but may have to find a new site, since the adults appear not to want the young eels to join them.
Skates and rays are the greatest predators of garden eels. If a garden eel is alert and fast enough to duck into its burrow, it is able to escape being eaten.
The life span of these eel species is between 35 and 40 years.
All garden eels appear to share the same characteristics and lifestyle. Their differences are their colors and markings, sizes, and where they live. No species of garden eel is considered threatened.
Bibliography
“Splendid Garden Eel.” Georgia Aquarium, 2024, www.georgiaaquarium.org/animal/splendid-garden-eel. Accessed 31 Mar. 2024.
“Spotted Garden Eel.” California Academy of Sciences, 2024, www.calacademy.org/learn-explore/creature-closeups/spotted-garden-eel. Accessed 31 Mar. 2024.