It was the only flightless passerine in the world. That distinction did not save it. Lyall’s Wren lived on Stephens Island, a small rock in Cook Strait. It ran rather than flew. Its wings were vestigial. It hid in the dark. Then the lighthouse keeper arrived. He brought a cat. The cat was named Tibbles. Tibbles did not care about distinctions. It hunted with efficiency. By 1895 the wren was gone. The entire species. One island. One cat. A complete erasure. The bird was small and brown. It resembled a mouse more than a typical wren. Its legs were strong. It foraged on the ground. Insects and spiders formed its diet. It did not sing loudly. It chirped softly from the shadows. Observers described it as shy. Shyness is a poor defence against a predator that does not sleep. Threats were singular and absolute. The introduction of the domestic cat to Stephens Island was the sole cause of extinction. There were no other factors. No disease. No habitat loss. Just a hungry animal in a confined space with naive prey. The wren had no evolutionary history with mammals. It did not recognise the threat. It stayed where it was. It died. Range was restricted to Stephens Island. Nowhere else. This endemism made it unique. It also made it vulnerable. A single stochastic event could wipe it out. In this case the event was deliberate human action. The lighthouse keeper kept the cat as a pet. The pet became a killer. The killer became an executioner. Habitat was dense coastal scrub and forest floor. The wren needed cover. It found none from Tibbles. The cat could climb. It could jump. It could wait. The wren could only run. Running is not enough when the hunter is faster. The last specimen was collected in 1894. By 1895 it was over. Silence followed. It remains silent today.