Christmas boobook lores and throat, yellow eyes, legs and feet. It is approximately 26–29 cm in length and 130-190 grams in weight with the female slightly larger than the male. The double-noted hoot, "boo-book," has a clucking quality with the second note usually lower in pitch. The begging call of juveniles is a high-pitched trill. Vocalisations are similar to those described for the Southern Boobook "N. novaeseelandiae" and include individual variation in advertisement calls. This may be useful in estimating owl densities as radio-tracking can be impractical in some terrains. A recording, courtesy of Richard Hill and Owl Pages http://www.owlpages.com/sounds/Ninox-natalis-2.mp3 Its natural
Ninox novaeseelandiae ocellata southern boobooks may directly correlate with rainfall, with the paler species being found in areas of lower rainfall, indicating the semi arid regions of Australia (the range of the ocellata sub species). The boobook has a very distinctive double hoot ‘boo-book’ with the second note being lower. This call has earned it the common name of ‘mopoke’. Subspecies ocellata tends to inhabit the warmer areas of Australia, from north-western New South Wales/western Queensland spanning across to Western Australia, although it is rarely found in the more arid regions. The boobook is found in a wide variety of habitats, from semi-arid