Food of the powerful owl ninox strenua in suburban brisbane, queensland

Powerful Owls are present in forest and woodland within several Australian cities including Brisbane (Pavey 1993), Sydney (Chafer 1992; Rose 1993), Wollongong (Chafer 1992) and Melbourne (Cooper 1964; McNabb 1987; Quinn 1994). There are over 20 sites within a 35 km radius of the Brisbane GPO where this species has been observed and is likely to be resident (CRP unpubl. data). This paper presents information on the food of Powerful Owls from two of these sites, to provide comparison with the prey taken at Mt. Coot-tha, where fruit-bats Pteropus spp. and the Common Ringtail Possum Pseudocheirus peregrinus were the main food of a pair of Powerful Owls (Pavey et al. 1994). Toohey Forest is 530 ha of woodland and open forest 10 km south of the Brisbane GPO; it is completely surrounded by urban settlement (Catterall 1987). A Powerful Owl was observed roosting in vine forest along Mimosa Creek (50-100 m asl), during MarchSeptember 1987, July 1988, May-June 1989, JanuaryAugust 1991 and February 1992. Pellets were collected below roosts from April 4-June 19 1987 (by R. Annels) and May 30-June 29 1989 (by CRP). A single pellet was collected in June 1991. Pellets were collected on average every eight days in 1987 (43 pellets) and every five days in 1989 (16 pellets). The bird was not observed holding prey. Bunyaville State Forest Park, 12 km north of the Brisbane GPO, is 620 ha of regrowth woodland and open forest. Vegetation on private property links it to a state forest to the west. A pair of Powerful Owls successfully reared a single young during 1993. Twenty-four pellets were collected between September and November 1993 (by R. McGuire), below roosts in vine forest along the upper branches of Albany Creek (20-70 m asl). The birds were observed holding prey, at the day roost or at night, on several occasions from September to December 1993. Prey material was examined either at the Queensland Museum (vertebrates) or the University of Queensland Insect Collection. Table 1 Food Items of Powerful Owls at three sites In suburban Brisbane; Toohey Forest (1987, 1989), Bunyavllle State Forest Park (1993) and Mt. Coot-tha (1989-91).