Morepork they conceded the two were easily distinguishable in appearance, so maintained the three as subspecies; the Tasmanian boobook only diverged by 2.7% from the other two, while the powerful and rufous owls diverged by 4.4% from each other. Leading from this, the southern boobook was split from the Tasmanian boobook and morepork in volume 5 of the "", however several authors, including Les Christidis and Walter Boles, contested that the data had been misinterpreted from the Norman study, which had not sampled any Australian mainland boobooks at all. They treated the three taxa (southern, Tasmanian boobooks, and moreporks) as a
Australasian grebe are about three-quarters grown. Initially the young will ride on the parents back, hidden between their slightly raised wings. When the chicks begin to dive and feed themselves (at about 10 weeks) the mother may leave too, although mothers have been known to return soon after, apparently to check on the chicks. The parents are very protective and will try to drive away other water birds (ducks, herons) by confronting them and flapping their wings wildly or using their wings to splash water at the intruders. Australasian grebe The Australasian grebe ("Tachybaptus novaehollandiae") is a small waterbird common on fresh