Morepork though he followed Mees in treating them as a single species. Janette Norman and colleagues tested the cytochrome "b" DNA of three subspecies (as well as the powerful and rufous owls) to ascertain whether the closest relative was used in breeding with the last surviving female of the Norfolk boobook. They discovered that although the Norfolk boobook was similar in plumage to the Tasmanian boobook, it was genetically much closer to the New Zealand subspecies. In fact, the two were so close genetically that they considered whether the Norfolk boobook should be recognised as a separate taxon at all, although
Penelope Diane Olsen Penelope Diane Olsen Dr Penelope Diane Olsen is an Australian ornithologist and author. She has worked with CSIRO as an experimental officer and an Honorary Research Associate as well as being an ARC Postdoctoral Fellow at the Australian National University. She is also internationally recognised as an expert on raptors and was involved in the conservation work on Norfolk Island for the Norfolk Island Boobook. She was President of the Australasian Raptor Association 1984–1989. In 1997 she was awarded the Royal Australasian Ornithologists Union's D.L. Serventy Medal for excellence in published work on birds in the Australasian region. Since 2003