The most common of the big kokopu. That does not mean it is easy to find. This is a fish that hides during the day and hunts at night. The body is long and sturdy. The head is broad and flattened. The mouth seems too big for its face. Colour ranges from mottled olive-brown to golden. Distinctive dark vertical bands run along the sides. Hence the name. These bands are the easiest way to tell it apart from its giant and shortjaw cousins. A fish that wears its name on its body. The pattern breaks up the outline. It aids concealment in dappled light. Night shift workers of the forest stream define this species. During the day, banded kokopu hide under overhanging banks. They shelter in root wads or under deep dark logs. They barely move. At night they emerge to hunt. They roam the shallows. They gulp down insects, worms, small crayfish and even baby mice if they can catch them. The mouth is enormous. It is used to create a vacuum. This sucks in anything that swims past. A fish that eats whatever fits. The capacity is surprising. The appetite is relentless. Guardians of the small stream describes their ecological role. If a banded kokopu is found, the water is clean. The forest is healthy. The bugs are plentiful. They are also terrible climbers. Unlike koaro, they cannot get past even a small waterfall. This is why they are found only in low-elevation streams near the coast. A fish that cannot climb. A fish that stays in the lowlands. The limitation defines the range. The geography dictates the presence. Absence signals degradation. Presence signals health. To see a banded kokopu is to see the spirit of the forest stream. It is a big lurking night-hunting predator. It keeps insects in check. It keeps the ecosystem in balance. This is the fish of the healthy stream. The one that tells, without saying a word, that this bit of bush is still doing alright. The indicator is silent. The message is clear. The survival depends on cover. The survival depends on quality. The stream is dark. The kokopu hides under the bank, waiting for night. The water is clean. The bugs are plentiful. The kokopu does not know it is a sign of health. It does not care about the assessment. It cares about the next meal. The instinct is simple. The requirement is specific. Clean water. Dark pools. Overhanging vegetation. Without these, it vanishes. With them, it persists. It carries on in the shadows. Unseen. Unvalued by the casual observer. But prized by those who know. The banded kokopu remains. A testament to the intact forest. A relic of the wild stream. It waits for dinner.