conger eel, hides in reef caves by day

Size
Length: 100–200 cm, Weight: 5–15 kg
Lifespan
20–30 years
Diet
Carnivorous feeder on fish, crabs, squid and octopus. Hunts at night using keen sense of smell. Hides in crevices during day. Attacks with fast, snake-like strike from den in rocky reefs.
Habitat
Inhabits rocky reefs, crevices, caves and wreck sites from shallow waters down to 100 metres depth. Prefers dark hiding places with access to open water for hunting. Often found in shipwrecks.
Range
Found in coastal waters of North and South Islands from Northland to Stewart Island. Most common in rocky harbours and along open coastlines. Also found in Australia and Southwest Pacific region.
Endemism
Native
Main Threats
Bycatch in rock lobster pots, set nets and bottom trawls is primary threat. Also threatened by habitat loss from coastal development. Climate change affects near-shore reef ecosystems. No targeted commercial fishery.
Population
Populations considered stable across most coastal habitats. Species not commercially targeted but often caught accidentally by recreational fishers and lobster potters. Large individuals becoming less common in easily accessed areas.
Conservation Status
Not Threatened
Snake of the rocky reef. This is an eel that hides in the dark. It stays in dark crevices and shipwrecks during the day. At night, it emerges to hunt crabs, octopus and small fish. Its powerful jaws can deliver a serious bite. The Māori names Koiro, Ngoio and Ngoiro reflect regional variations. They also refer to the eel's sinuous, secretive nature. Despite its fearsome appearance, it is not aggressive unless provoked. An eel that is secretive. The reputation is earned but often misunderstood. The body is long and cylindrical. It tapers to a pointed tail. The skin is thick and slimy. Colour is dark brown or grey on the back. It fades to pale on the belly. The head is broad. Large eyes and a wide mouth filled with sharp teeth define the face. Dorsal and anal fins are continuous. They run the length of the body. The morphology supports the lifestyle. Flexibility is key. Strength is required. Camouflage aids survival. Nocturnal predator describes the behaviour. Days are spent hidden in crevices. Under rocks or inside shipwrecks provides shelter. Night brings activity. Hunting uses a keen sense of smell to locate prey. It is an ambush predator. Waiting happens in its den. Prey must pass within range. The patience is absolute. The strike is sudden. The outcome is decisive. When it strikes, speed is paramount. It grabs the prey with its teeth. It wraps its body around it. Constriction happens like a snake. It swallows its prey whole. Head first is the method. The efficiency is high. The energy cost is managed. The meal is secured. The cycle repeats. Aggression toward humans is not typical. Most bites occur when a diver reaches into a crevice. The eel strikes in self-defence. Leave them alone, and they will leave you alone. The rule is simple. The consequence is clear. The interaction is avoidable. The risk is minimal if respect is shown. Not targeted by commercial fisheries. It is often caught accidentally by recreational fishers. And in rock lobster pots. The rocky reef is dark. The conger eel hides in a crevice. Thick and sinuous. Waiting for night. A diver reaches in. The eel strikes. The diver pulls back. The eel retreats. It does not know it is feared. It does not know it is secretive. It just wants to eat a crab. A fish of the rocks. Of the wrecks. Of the deep shadows. The conger eel is proof. It carries on in the depths. Unseen. Unvalued by the casual observer. But noted by those who know. It remains in the crevice. A testament to the intact reef. A relic of the wild dark. It waits for the prey. Or it does not. The choice is random. The outcome is certain. The eel persists.