tusked weta with curved tusks used in rival male combat

Size
Body: 3–5 cm
Lifespan
2–3 years
Diet
Omnivorous: feeds on decaying plant matter, fungi, small insects and other invertebrates. Named for distinctive tusks (elongated mandibles) of males, used for fighting other males.
Habitat
Damp, muddy banks of streams and rivers. The sabre-toothed specialists of the wētā world, particularly fond of waterfront property where they can easily retreat into deep, water-filled burrows.
Range
Isolated pockets of North Island and Mercury Islands, particularly in Coromandel, Bay of Plenty and Great Barrier Island. Most common in damp, muddy banks of streams and rivers in native forest catchments.
Endemism
Endemic
Main Threats
Habitat loss from forest clearance and drainage of wetlands. Predation from rats, pigs and introduced birds which disturb stream banks. Water pollution from agricultural runoff which degrades aquatic habitat.
Population
With only a few species tucked away in isolated pockets of North Island and Mercury Islands, they are one of New Zealand's most elusive invertebrates. Once thought to be quite rare until conservationists realised they were just looking in the wrong, drier places.
Conservation Status
Nationally Vulnerable
The walrus of the New Zealand undergrowth. An insect with tusks. That is not a sentence that makes sense, but it is true. The tusked wētā is a master of amphibious survival and riparian guarding. Its anatomy is defined by the massive, curved tusks protruding from the mandibles of adult males, specialised heavy-duty bumpers utilised exclusively for high-stakes wrestling matches over territory. An insect that fights with its face. Unlike the arboreal residents of the canopy, these tusked warriors represent a state of resourceful industry along the water's edge. They are powerful swimmers, capable of diving underwater to evade predators by trapping a thin film of air against their bodies. This submerged retreat allows them to remain underwater for several minutes at a time. An insect that can hold its breath. The life cycle of the tusked wētā is a definitive sign of waterway health, as they are highly dependent on stable, unpolluted banks for their subterranean hoard of eggs. Females lack the tusks of the males, focusing their anatomy on a long, curved ovipositor used to secure the next generation deep within the riverbank silt. A female that does not need tusks. She has other weapons. Functioning as opportunistic scavengers, they move energy between the stream-side buffet and the forest floor, acting as a hidden guardian of the riparian zone. Currently classified as nationally vulnerable, tusked wētā are foundational participants in the freshwater-terrestrial interface of New Zealand. To encounter a tusked warrior on a damp riverbank is to witness a survivor that has mastered the art of the hidden guardian. The riverbank is damp. The wētā hides under a stone, tusks gleaming, waiting for night. It does not know it is vulnerable. It does not know it is rare. It just waits. That is what guardians do.