It was a subspecies of the rock wren. It is unrelated to the rock wren of North America. Small numbers of rock wren have been recorded in Victoria Forest Park. Hard to see is the tiny rifleman and New Zealand's smallest bird Rock Wren. On the mainland, rock wren are threatened by introduced predators. This rock wren was the only endemic terrestrial bird on San Benedicto. Wildlife of the mountains includes the endemic rock wren "(Xenicus gilviventris)". In the Murchison Mountains, rock wren showed a 44% decline in abundance over 20 years.