The ribbon eel, or Rhinomuraena quaesita, is a visually striking moray eel found in the Indo-Pacific’s shallow reefs and lagoons. It is the sole member of its genus, recognized by its long, thin, ribbon-like body and prominent, flared sensory appendages on its nostrils. Ribbon eels undergo a complete color and sex transformation throughout their life, progressing from black juveniles to bright blue males and finally to yellow females. As a specialized predator, the eel’s survival depends on its diet and the hunting techniques it employs from its burrow.
The Primary Prey of Ribbon Eels
Ribbon eels are strict carnivores, feeding almost exclusively on small, live organisms found in their immediate reef environment. Their slender body shape and reliance on a fixed ambush location dictate that prey must be small enough to be swallowed whole and pass close to their hiding spot. The bulk of their natural intake consists of small, benthic-dwelling fish, making them primarily piscivorous. These fish often include species like gobies, blennies, and juvenile wrasses that swim along the bottom or near the entrance of the eel’s burrow. They are also opportunistic feeders and readily consume small crustaceans, such as shrimp and tiny crabs, that venture within striking distance.
Unique Hunting and Feeding Strategies
The ribbon eel is an ambush predator that employs a “sit-and-wait” strategy to conserve energy. The eel typically excavates a burrow in a sandy patch or rock rubble, lining it with mucus for protection. It remains hidden with only its head and the first few inches of its body exposed, allowing it to monitor the surrounding water column and substrate without fully exposing its vulnerable body.
The flared, tubular nostrils of the ribbon eel are highly developed sensory organs. These organs allow the eel to detect prey primarily through smell (olfaction) rather than sight. This keen sense of scent is crucial for locating small fish and crustaceans moving through the currents, especially since the eel is often most active at dawn and dusk. Once a target is sensed and moves into the strike zone, the eel executes a lightning-fast, snap-strike lunge.
This rapid capture is facilitated by an advanced jaw apparatus unique to moray eels. After the oral jaws bite and secure the prey, a second, specialized set of pharyngeal jaws is projected from the throat. These pharyngeal jaws are equipped with sharp, backward-curving teeth that grasp the struggling prey and pull it deep into the eel’s gullet. During the strike, the eel anchors its long, ribbon-like body deep within the burrow, preventing the prey’s struggle from pulling the eel out into the open.
Dietary Shifts Across Life Stages
Although the ribbon eel undergoes dramatic changes in color and sex, the fundamental nature of its diet remains relatively consistent. All phases are carnivorous, primarily targeting the same types of small fish and crustaceans within their local habitat. The main change in feeding behavior is correlated with the eel’s increasing size as it matures. A newly settled black juvenile consumes very tiny prey, while a fully grown yellow female, which can reach over one meter in length, is capable of ingesting slightly larger fish and crustaceans. Juveniles are often spotted on more open sandy or rubble patches, while larger adults are more frequently found in areas with higher coral density, a subtle shift that may indirectly affect prey availability.