Southern boobook taxa (southern plus Tasmanian boobooks and moreporks) as a single species. Examining both morphological and genetic (cytochrome b) characters in 2008, German biologist Michael Wink and colleagues concluded that the southern boobook is distinct from the morepork and Tasmanian boobook (which they proposed to be raised to species status as "Ninox leucopsis"), and that it is instead the sister taxon to the barking owl ("N. connivens"). A 2017 study by Singapore-based biologist Chyi Yin Gwee and colleagues analysing both multi-locus DNA and boobook calls confirmed a sister relationship of "N. n. novaeseelandiae" and "N." ("n.") "leucopsis" and their close relationship
Southern boobook grasshoppers, crickets, beetles, cockroaches, moths, wolf spiders, and huntsman spiders were also consumed. A study in Victoria found that larger animals were eaten, including Baillon's crake ("Porzana pusilla"), common ringtail possum ("Pseudocheirus peregrinus") and feral rabbit ("Oryctolagus cuniculus"). Using a fence, branch, or telegraph pole as a perch or vantage point from which to hunt, the southern boobook pounces on prey then retreats to a tree or elevated place to eat it. It often hunts in open areas near trees, and also where prey is likely to congregate, such as mice near haystacks or barns, or flying insects near street-