The Lembeh Strait is home to rare marine species. Its volcanic sands support strange and colorful life. Divers visit the area to see creatures found nowhere else. One of the most unique is the Mandarinfish (Synchiropus splendidus). Its bold pattern and bright colors make it stand out on the sandy floor of Lembeh.
What is a Mandarinfish?
Mandarinfish (Synchiropus splendidus), also known as mandarin dragonets, are tiny fish known for their unique looks. With a size of around just 6 to 8 inches long, the mandarinfish’s bodies are adorned with a unique pattern of swirling blues, oranges, greens, and yellows. This color resembles the embroidered robes worn by Chinese imperial officials, which inspired their common name.
The Unique Mating Ritual That Made Mandarinfish Famous
One thing that makes Mandarinfish popular is their mating ritual. It happens at dusk, during a short window of time when males flare their fins and circle nearby females. If a female accepts, the pair swims upward in a slow, synced rise. At the top, they release their eggs and sperm, then vanish into the reef.
Lembeh Strait is one of the best places in the world to see this, due to its ideal environment for this fish to thrive. With the right guide and timing, you float quietly near the reef as the mandarinfish rise in front of you. Their colors glow in the last light of day, framed by still water and a softening sky. It’s a favorite for photographers and one of the most rewarding behaviors to witness underwater.
Where Do Mandarinfish Live?
Mandarinfish live in shallow, sheltered reefs with lots of coral rubble and sand. They like areas with plenty of hiding spots, such as broken coral and small crevices, because these places offer safety during the day and space for their evening mating ritual.
Their range spans across the Indo-Pacific, with strong populations in Southeast Asia. These include the Philippines, Papua New Guinea, and several parts of Indonesia, such as Bali, Ambon, and Sulawesi. Among all these locations, Lembeh Strait is especially well-suited for Mandarinfish encounters.
What Does Mandarinfish Eat?
Mandarinfish are carnivorous micropredators that feed on tiny benthic invertebrates, such as copepods, worms, and small crustaceans, which they consume using the suction on their small, protruding mouths from the coral rubble. Their presence is often a sign of a healthy, biodiverse shallow reef.
Mandarinfish Unique Survival Tactics
Despite their vivid appearance, mandarinfish have evolved smart ways to avoid being eaten. What looks like a bright target is actually part of their defense. In the broken patterns of coral rubble, their bold colors create visual confusion, helping them blend into their surroundings more effectively than expected.
In addition to camouflage, mandarinfish rely on a unique chemical defense. Their skin is coated in a bitter, foul-smelling mucus that discourages most predators from taking a second bite. This natural deterrent makes them far less appealing than other small, slow-moving reef fish.
Their unique behavior also plays a role in surviving the sea. During the day, mandarinfish stay hidden in crevices and under rubble, venturing out only at dusk when many predators are less active. And when startled, they quickly dart into cover, using their agility and knowledge of the reef to stay safe.
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When and Where to See Mandarinfish in Lembeh
Mandarinfish can be seen in Lembeh Strait throughout the year. The best time to watch their mating display is at dusk, when they briefly emerge from hiding. Lembeh’s calm waters and minimal currents make it perfect for slow, steady observation.
One of the top places to spot them is the Bianca dive site, known for its coral rubble and sheltered conditions, making it a popular location for mandarin dives. Using their knowledge, local dive guides will be able to lead you straight to these well-hidden fish.
Responsible Observation Etiquette for Divers
Witnessing the mandarinfish mating display is a privilege, and responsible observation is paramount to ensure the fish are not disturbed.
- Maintain Distance: Keep a respectful distance, using your macro lens to get close-up shots rather than physically encroaching on their space.
- Limit Light: mandarinfish are sensitive to bright lights. Red focus lights are often used by guides and photographers as they are less disturbing to nocturnal creatures. Avoid continuously blasting them with bright white lights or repetitive, high-power flashes.
- No Touching or Manipulation: Never touch, poke, or attempt to move the fish or their habitat for a better view or photo. This can cause extreme stress and disrupt their natural behavior, potentially impacting their reproductive success.
- Limit Dive Time: Once you’ve had a chance to observe, move on to allow others the opportunity and to minimize cumulative disturbance to the fish. Many resorts, including Solitude Lembeh, educate divers on these ethical guidelines.
Related reads: The Complete Guide to Underwater Photography for Beginners
Ready For Mandarin Dive with Solitude?
Mandarin diving is a slow and peaceful experience, perfect if you enjoy observing marine life up close. As the sun sets, mandarinfish emerge from their hiding spots to perform a short but fascinating mating dance. We wait quietly near coral rubble, using red lights to avoid disturbing the fish, capturing every moment of the dance.
At Solitude Lembeh Resort, the team takes care of every detail so guests can enjoy the moment. PADI-certified guides handle the timing and guide you gently through the dive, making it easy and stress-free. Afterward, you return to your private villa, where a warm shower and a freshly prepared home-cooked meal are waiting. It’s the perfect way to end a day of diving.
Book your next adventure with Solitude Lembeh Resort and experience the magic of mandarin diving for yourself!