Wekas have been on Macquarie Island for just over 100 years. They occur in the coastal tussock grassland, mainly in the northern half of Macquarie Island. Males are larger than females and the sexes can be separated on a combination of culmen and tarsus lengths. The sex ratio in favour of males was considered to be due to behavioural differences. Breeding begins in August and, although four eggs may be laid, only one or two chicks are usually reared. Losses are probably due to predation by feral cats and skuas. Preferred foods are vegetation, insects and spiders. Mammal and bird remains were present in fewer than half the gizzards examined, but rats and mice are thought to be important food because of their size.