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
Australasian bittern species is listed as endangered. BirdLife International has identified the following sites, all of which are in Australia, as being important for Australasian bittern conservation: Australasian bittern The Australasian bittern ("Botaurus poiciloptilus"), also known as the brown bittern or matuku hūrepo, is a large bird in the heron family Ardeidae. A secretive bird with a distinctive booming call, it is more often heard than seen. Australasian bitterns are endangered in both Australia and New Zealand. The length is from 650 to 750 mm with adults being similar between the sexes while the male is significantly larger. The bird has a