Ribbon Eels in Thailand: Color-Shifting Wonders of the Andaman Sea

By Sorrasek Phiboonthammasak Date 23 Jul 2025

Ribbon eels are among the most mesmerizing creatures you’ll encounter while diving in Thailand’s tropical waters. These slender, snake-like members of the moray eel family captivate divers with their vibrant colors and graceful, flowing movements. Named "ribbon eels" for their long, thin, ribbon-like bodies that can reach up to 1.3 meters, they sway in the ocean currents like a living streamer. What makes them truly stunning is their ability to change colors and even gender as they age, transforming from jet-black juveniles to electric-blue males and bright-yellow females. For scuba enthusiasts exploring Thailand’s reefs, spotting a ribbon eel is a bucket-list moment that showcases the magic of the underwater world.

Basic Scientific Information About Ribbon Eels

Ribbon eels, scientifically known as Rhinomuraena quaesita, belong to the moray eel family, Muraenidae. Their unique, elongated bodies lack pectoral and pelvic fins, giving them a serpentine appearance. They feature distinctive flared nostrils shaped like a leaf, which help them detect prey. Growing to 70–130 cm and weighing about 1–2 kg, these carnivorous eels are solitary and spend most of their lives in burrows, with only their heads poking out. They can live up to 20 years in the wild, though their reproductive phase shortens this. Ribbon eels breathe by rhythmically opening and closing their mouths to pump water over their gills, and while they have sharp teeth for catching prey, they pose no threat to divers unless provoked.

Interesting Fact: Color and Gender Changes with Age

One of the most fascinating traits of ribbon eels is their ability to change both color and gender as they mature. All ribbon eels start life as males, born with a black body and a yellow dorsal fin. As they grow into adult males, their bodies turn a striking blue with yellow accents around the face and fin. Later in life, some transition into females, becoming entirely yellow while developing female reproductive organs—a process called sequential hermaphroditism. This remarkable transformation is influenced by environmental and social factors, ensuring balance in their populations. Spotting a ribbon eel in each color phase—black, blue, or yellow—is like witnessing a living work of art.

The Life Cycle of Ribbon Eels

The life cycle of a ribbon eel is as captivating as its appearance. It begins with eggs released into the open ocean, hatching into transparent, leaf-like larvae called leptocephali. These larvae drift with currents for months or even years before settling onto reefs. As juveniles, they adopt their black coloration and burrow into sandy or muddy substrates. As they mature into blue males, they become sexually active. Eventually, some transition to yellow females, typically around 90–100 cm, after which they mate, lay eggs, and often pass away within a month. This rapid reproductive cycle keeps their populations thriving in dynamic reef ecosystems.

Habitat of Ribbon Eels

Ribbon eels inhabit warm, tropical waters, favoring lagoons, coral reefs, and sandy flats at depths of 1–50 meters. They prefer areas with loose sediment where they can dig burrows, often near coral heads or rubble for protection. Found across the Indo-Pacific, from East Africa to French Polynesia, they thrive in water temperatures of 24–29°C with moderate currents that bring food. During the day, they remain mostly hidden in their burrows, emerging slightly to hunt or breathe, making them a thrilling find for divers exploring these vibrant habitats.

Behavior: Hunting, Diet, and Daily Life

Ribbon eels are ambush predators, lurking in their burrows with their jaws open to attract prey. They feed on small fish and crustaceans, striking swiftly with their sharp teeth. Their flared nostrils help detect chemical cues in the water, making them efficient hunters. These solitary eels spend most of their time in burrows, swaying their bodies to oxygenate water over their gills—a motion that looks like an underwater dance. While nocturnal by nature, they’re often visible during the day, making them accessible to divers. Though not aggressive toward humans, they may bite if disturbed, so respect is key.

Where to Find Ribbon Eels in Thailand

Thailand’s Andaman Sea is a hotspot for ribbon eel sightings, thanks to its pristine coral reefs and sandy bottoms. The Similan Islands are a top destination, with dive sites like East of Eden and Turtle Rock offering ideal conditions for spotting ribbon eels in burrows among rubble and soft corals. Richelieu Rock, a world-famous pinnacle, is another prime location where these colorful eels often hide. Koh Bon and Koh Tachai in the Similans are also known for ribbon eels in deeper sandy areas. Joining a liveaboard trip to these sites offers the best chance to see juveniles, males, and females in a single adventure.

How to Approach Ribbon Eels

Approaching a ribbon eel requires patience and care to avoid startling them. Move slowly and maintain a distance of 1–2 meters at first, as sudden movements can cause them to retreat into their burrows. Descend calmly to their depth, typically 10–30 meters, and observe from afar before inching closer. Never touch or poke their burrows, as this stresses them and could lead to a defensive reaction. Excellent buoyancy control is crucial to avoid stirring up sand, which can cloud the water and ruin your view. A respectful approach ensures a safe and rewarding encounter.

How to Photograph Ribbon Eels

Capturing the beauty of ribbon eels on camera is a highlight for underwater photographers, but it takes skill. Use a macro lens (50–105mm) to highlight their intricate faces and vibrant colors. Approach slowly to get as close as your lens allows, zooming in to frame their head or open mouth for dynamic shots. A shallow depth of field can isolate the eel against a blurred background, making their colors pop. Time your shots during their rhythmic “breathing” motions for natural poses, and use strobes to enhance colors in low-light conditions. Patience is essential—wait for them to fully emerge for the perfect shot.

Conclusion

Ribbon eels in Thailand are a dazzling testament to the wonders of marine life, with their color-changing, gender-shifting journey and graceful presence in the Andaman Sea’s reefs. From their ambush hunting to their serene burrow-dwelling habits, these creatures offer divers an unforgettable experience. To witness their magic up close, book a dive trip with Giant Stride, experts in crafting exceptional scuba adventures to Thailand’s top sites like the Similan Islands and Richelieu Rock. Dive in with Giant Stride and let ribbon eels weave their spell on your next underwater journey!

Don’t Forget to share this post