Whose hoot? Identity of unknown owl revealed

Excitement stirred when a small unidentified owl was found dead on Lord Howe Island; Australian Museum scientists have now identified the wayward individual.

When a small dark brown, spotted owl was found dead on Lord Howe Island in 2019, locals wondered what species it could be… Could it be the presumed extinct Lord Howe Morepork (Ninox novaeseelandiae albaria)? Australian Museum scientists, Department of Planning and Environment scientists and the Lord Howe Island Board used comparisons with AM museum specimens and performed DNA analysis to determine that the owl was, in fact, a Tasmanian Boobook (Ninox leucopsis) far from home.

In July 2019, the Australian Museum was sent a frozen specimen of a spotted dark brown owl that was found dead on Lord Howe Island by a local resident. Based on plumage characteristics, the bird belonged to the Ninox owls, a group which include the formidable Powerful Owl (Ninox strenua) and the smaller boobook and morepork owls.

The Southern Boobook (Ninox boobook) is one of the most widespread owl species found across mainland Australia. The smaller Tasmanian Boobook (N. leucopsis) is recognised by some authorities as a separate species and is found in Tasmania, with occasional migration to southern Victoria. An endemic subspecies of the Tasman Morepork of New Zealand (N. novaeseelandiae) previously found on Lord Howe Island – called the Lord Howe Morepork (Ninox novaeseelandiae albaria) – became extinct in the 1950s.

When the owl was found, some locals on Lord Howe Island expressed concern that it was an individual of the endemic, and extinct, Lord Howe Morepork. However, through comparing and analysing plumage characteristics and measuring parts of the wings, bills, and feet of museum specimens from the Australian Museum and the American Museum of Natural History, as well as undertaking DNA analysis it was determined that the specimen was in fact a Tasmanian Boobook (N. leucopsis). But how did the owl end up there from Tasmania? One explanation was a significant weather system that had passed over Lord Howe Island not long before the owl was found, so it’s possible that the owl was blown way off course on its journey between Tasmania and the mainland.

In any case, the occurrence of a Ninox species on Lord Howe Island for the first time in 50 years is something to celebrate and certainly explore further!

Dr Leah R. Tsang, Collection Manager, Ornithology, Australian Museum.

Dr Mark Eldridge, Principal Research Scientist, Terrestrial Vertebrates, Australian Museum.

Dr Greta Frankham, Scientific Officer, Australian Centre for Wildlife Genomics, Australian Museum.