Southern boobook smallest owl on the Australian mainland, the southern boobook is long. The nominate subspecies is the largest. It has short, rounded wings and a short tail, with a compact silhouette in flight. Southern boobooks on the Australian mainland follow Bergmann's rule, in that birds from cooler and more southerly parts of the range tend to be larger. Thus, birds from the Canberra region weigh around while those from the Cape York Peninsula and Broome are around . Females tend to be a little larger and heavier than males, with males weighing and females . The southern boobook has generally dark
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