Ribbon eels (Rhinomuraena quaesita) are aptly named for their delicate movements, as they swim like a slender ribbon dancing in the water column. Technically, all ribbon eels are moray eels. This enigmatic creature, adorned with a kaleidoscope of colors, adds a touch of magic to its coral reef and mangrove habitats.
These colorful species are considered protandrous hermaphrodites, beginning life as a males, and as they mature, they switch sexes to females, developing female sex organs once ready to reproduce. Ribbon eels are long-lived, living up to 20 years in the wild.
Let’s delve into the fascinating world of this extraordinary fish, exploring its captivating appearance, unique biology, and ecological significance.
Appearance
Ribbon eels are colorful, slender-bodied animals with all species beginning their lives as black-bodied and a yellow ribbon along the dorsal fin. Depending on the life stage, ribbon eels turn blue and finally yellow. Juveniles are always black.
The ribbon eel, one of over 200 species of moray eels, turns blue once reaching 66 to 102 cm (26 to 40 in.) At a maximum length of 130 cm (4 ft.), the ribbon eel turns yellow. Leaf-like elongations of the anterior nostrils serve as antennae to minute changes in the environment, helping them to hunt and defend themselves.
They possess a slender, snake-like body that is laterally compressed (flattened from the sides). Iridescent blues, greens, yellows, and oranges can adorn their bodies, often with contrasting stripes, spots, or marbled patterns. Their head is relatively small compared to their body length, with a pointed snout and tiny eyes.
Rainbow eels have long, continuous dorsal (top) and anal (bottom) fins that run along most of their body length. Small, fan-like pectoral fins located behind their head
Their small eyes suggest they rely heavily on other senses, such as smell and the ability to detect vibrations, to navigate and locate prey.
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They are primarily nocturnal, emerging from their burrows at night to hunt for food. They are adept at burrowing into sand or mud using their pointed snouts and flexible bodies. This provides shelter from predators and access to prey within the substrate.
Habitat
Ribbon eels are found in the Pacific Ocean and Indonesian waters from East Africa to southern Japan, Australia, and French Polynesia. These eels live in lagoons and coastal reefs, taking shelter in crevices and burrows.
They are most often seen with their heads and part of their anterior bodies extended from their hiding places. Living amongst the reefs, they can be found from one to over 200 feet down. Most interesting is that males are known to share space with each other in their burrows and hideouts.
Diet
As a carnivorous eel, this species eats small fish and crustaceans (shrimp or crabs). It is nocturnal, leaving its small reef crevices only under darkness. These eels naturally hold their heads out of their burrows, allowing them to ambush unsuspecting fish.
They clamp their leafy nostrils to attract prey and catch items with their strong jaws.
Reproduction
When the water is warmest, they will come together to mate. Females die soon, typically within one month, after laying leafy-shaped eggs that float within the water column for about eight weeks.
As protandric hermaphrodites, these eels can change their sex as they mature into different life stages. All of them start life as males and become females when they are sexually mature and ready to mate. If a black/yellow or blue/yellow ribbon eel is spotted, it is sure to be known as male. Once they turn all yellow, we know them to be in the female and final stage of life.
Threats
They have a conservation status of Least Concern, the home aquarium trade is their number one threat. Sought after for their beauty, these specimens rarely live beyond a single month in captivity.
Natural threats are larger fish and sea birds.
6 More Fun Facts about Ribbon Eel
- Like other moray eel species, the ribbon eel can be found with its mouth in an open position, closing it over and over. This is not an aggressive behavior but rather a way to circulate water over their gills.
- They are unlikely to change their living territory, so they may live in the same spot for many years.
- During the larvae stage, the ribbon eel’s body is transparent.
- They can fit into tiny, narrow crevices along the reefs where they live.
- Eggs that are laid by the female float about the ocean for eight weeks before hatching.
- Females die within one month of laying eggs.
FAQs
Do Ribbon Eels bite humans?
Ribbon eels are not known to bite humans, though they certainly could if cornered. They look aggressive as they open and close their mouths over and over while sticking their heads out of their burrows. This is a way to move water over their gills and is not meant as a threat.
Why is it called a Ribbon Eel?
Though rarely seen swimming outside of their burrows and crevices, the ribbon eel looks like a dancing ribbon with its tall dorsal fin, while it swims in open water.
Are these eels aggressive?
When threatened or defending territory, they may display aggressive postures, including gaping their mouths, flaring their elaborate nostrils, and even biting. However, they are not inherently aggressive towards humans and typically avoid confrontation unless provoked or cornered.
Do all ribbon eels turn female?
All of them undergo a remarkable transformation, starting as males and transitioning into females later in life. This is known as protandrous hermaphroditism. As they mature and grow larger, hormonal changes trigger
- Ribbon Eel
The ribbon eel, Rhinomuraena quaesita, is fundamentally classified within the Moray eel family, Muraenidae. A profound biological characteristic of this species is its protandrous hermaphroditism: individuals initiate their life cycle as males, subsequently undergoing a complete sex reversal to females upon reaching reproductive maturity.
Furthermore, the ribbon eel exhibits remarkable longevity, with documented lifespans extending up to two decades within its natural habitat, underscoring its resilience in complex reef ecosystems. Continue reading to uncover its unique behaviors, habitat, and conservation status.
Appearance
The ribbon eel is renowned for its striking and dynamic coloration, a characteristic directly linked to its unique life cycle. All individuals commence their lives as juveniles, exhibiting a distinct jet-black body contrasted sharply with a vivid yellow dorsal fin that extends along their entire length. This initial phase transitions dramatically as the eel matures.
They experience a remarkable change in color as they progress through their life cycle Upon reaching a length of approximately 66 to 102 centimeters (26 to 40 inches), the ribbon eel undergoes a remarkable color transformation, becoming a vibrant blue with the dorsal fin retaining its yellow hue.
This blue phase signifies the male stage of its life. Subsequently, as the eel continues to grow, potentially reaching a maximum length of 130 centimeters (approximately 4 feet), it transitions into its final, female stage, where its entire body becomes a uniform yellow.
Its exceptionally slender, ribbon-like body gives the species its common name, allowing for highly agile and undulating movements.
They spend the majority of their time concealed within the intricate structures of coral reefs, rocky outcrops, or sandy and rubble substrates. They are often seen with only their heads protruding from a crevice or burrow, patiently awaiting prey. This behavior is a...
