The conference was held in Australia and several chapters of the book are dedicated to the study of Australian owls. We can see that there is some concern about the habitats of a few species, especially in Victoria, in the forests and grasslands near Melbourne. None of the species is seen as near extinction, but the trends of shrinking numbers is worrisome.
At least for the owls in the south west of Western Australia, from Augusta to Albany, the situation was stable. Likewise in Queensland.
Overall, you might have admiration for these magnificent raptors, all over the world.
The proceedings were held before global warming became a prominent concern. Today, some 12 years later, it has been noted in Australia that temperatures are gradually rising and rainfall decreasing in some regions, including those covered in the text. Reading the book today raises the suggestion that further environmental stress might occur. Especially because the owls needs a fairly temperate climate and cannot survive in an actual Outback situation.