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 Individual Speedway Championship Stadium in Auckland, was won by Maury Dunn. In the years 1970, 1971 and 1972, an Australasian Grand Prix meeting was held at the Liverpool Speedway in Sydney on the original "D" shaped track and not the bike track that was built on the infield in 1974 when the Liverpool track surface was changed to asphalt. All three Australasian GP's were won by New Zealand's Ivan Mauger. The first Australasian Final qualifier was held at the Western Springs Stadium on 21 February 1976 with dual Australian Champion John Boulger emerging as the winner. The last Final was held at the