survives on alpine rock and nothing else

Size
Length: 9–10 cm, Weight: 12–16 g
Lifespan
5–7 years
Diet
Insectivorous - feeds on small insects, spiders, and larvae. Forages on the ground and among rocks, hopping and flitting between boulders, using its long, thin bill to probe into crevices and under stones. Well adapted to the alpine environment, with thick, fluffy feathers for insulation.
Habitat
High-altitude alpine and subalpine rock screes and basins. Ghosts of the screes, perfectly camouflaged against grey rocks and pale lichen. Requires extensive areas of stable rock screes with deep crevices for nesting and shelter, and good insect populations for food.
Range
Found only in the South Island, in high-altitude alpine and subalpine rock screes and basins from north-west Nelson and Marlborough down to Fiordland and Southland. Most common in the Murchison Mountains, the Humboldt Mountains, the Southern Alps, and Kahurangi National Park.
Endemism
Endemic
Main Threats
Predation by stoats is the primary threat, with stoats having spread into alpine areas following the introduction of mice and rabbits. Also threatened by climate change, which reduces alpine habitat and allows predators to survive at higher elevations, and by disturbance from trampers and ski field development.
Population
One of New Zealand's most threatened alpine birds, classified as Nationally Critical, the highest threat classification possible. The population is estimated at fewer than 5000 birds and declining. Confined to a few strongholds in Fiordland, the Southern Alps, and north-west Nelson, where intensive stoat control keeps them alive.
Conservation Status
Nationally Critical
A tiny bird built for edges. Brown, speckled, subtle. The camouflage makes a person think they imagined it until it moves. The tail flicks constantly. The wings beat quick and precise. The eyes are dark. They are alert. They measure every rock, crevice, and shadow. This is the Tuke. It lives among the high alpine scree and rocky slopes. This is the kind of place where wind whips. Nothing soft grows here. It hops and flits between stones. It is fearless of heights. It is always on the lookout for insects and small invertebrates hiding under rocks. A bird that has made its peace with exposure. The Tuke is solitary or in pairs. It is quiet but deliberate. Its calls are thin and high-pitched. They are almost a whisper against the roar of the mountains. Yet they are unmistakable once learned. Nests are tucked under rocks or in cracks. They are small and neat. They are protected from wind and prying eyes. A nest that asks to be overlooked. It survives in extreme conditions. It is always moving. It is always present. Small, tough, and astonishingly precise, it is a bird that thrives where few others would dare. The alpine zone is not kind. The rock wren does not ask it to be. The Maori name is Tuke. It refers to the bird's habit of flicking its tail. This is a small gesture of constant alertness. The people who came before knew this bird. They saw it on the high slopes. They saw it in the places where only the determined go. To see a Tuke is to glimpse determination distilled into a few grams of feather and muscle. It is a silent, hopping proof that life can insist on itself even in the harshest corners. It does not ask for admiration. It just keeps hopping. That is the rock wren. Small. Tough. Precise. A bird of the high places. The kind of bird that makes a person feel large and clumsy just by being there. No one told it otherwise. It carries on. The wind blows. The rocks shift. The bird remains. It is a ghost of the screes. Perfectly camouflaged against grey rocks and pale lichen. It requires extensive areas of stable rock screes. It needs deep crevices for nesting and shelter. It needs good insect populations for food. Without these, it cannot survive. With them, it persists. It is a testament to resilience. Not the loud kind. The quiet kind. The kind that endures.