Several species of owl were introduced to Lord Howe Island in the 1920s in an attempt to control black rats (Rattus rattus). Experts beleive that the Lord Howe southern boobook (Ninox novaeseelandiae albaria) disappeared from the island in the 1950s, and that the introduced Australian masked owl probably preyed on the boobook, which may have caused its extinction (NSW Office of Environment & Heritage, 2020). Owls are known to prey on other owl species (see Mikkola, 1976), and the Australian masked owl is a large powerful owl - the native boobook owl was a relatively small species by comparison. Indeed, the Australian masked owl is known to prey on other boobook species in its native range (NSW Office of Environment & Heritage, 2020). However, there is no direct evidence of Australian masked owls preying on the Lord Howe southern boobook on Lord Howe Island. Other possible causes of the boobook's extinction include competition from other introduced owl species such as the barn owl (Tyto alba), and predation by black rats.