Small, fast and intensely metallic. The common copper butterfly is an anatomical study in visual contrast. When it spreads its wings to bask in the sun, it reveals a brilliant orange-gold surface etched with a complex lattice of black veins. The effect is dazzling. A flash of copper in the summer light. But when the butterfly closes its wings, it instantly vanishes. The undersides are a dull, camouflaged grey-brown. They are patterned to look like a dead leaf or a patch of dried mud. This now-you-see-me-now-you-don't survival strategy allows the common copper to thrive in exposed environments. Riverbeds, coastal dunes and open grasslands are home to them. Predators are abundant there. The larvae are slug-like masters of the vine. They are green, flattened and perfectly camouflaged against the succulent leaves and wiry stems of their host plant, Muehlenbeckia. Also known as wire vine. They feed during the day. Their slow, deliberate movement and excellent camouflage make them nearly invisible to birds. When disturbed, they drop to the ground. They play dead. Males are territorial and aggressive. They perch on low plants in sunny clearings, waiting for females to pass. When another male enters his territory, the resident chases him away. The flight is a furious zigzag that can last for minutes. The males never wander far from their patch. They defend it day after day. The common copper is a low-altitude flier. It rarely strays more than a metre above the ground. It skips between bushes with a fast, erratic flight. It settles frequently with wings closed, basking in the sun. You need to move slowly to approach one. Sudden movements send it darting away. A tiny copper spark vanishing into the grass. This butterfly is endemic to New Zealand. It is found only here. It is the most widespread of our native coppers. But its habitat is under threat. Coastal dunes are being developed. Riverbeds are being modified. The Muehlenbeckia vines are being cleared.