Whilst looking at references on the Fan-tailed Cuckoo, I'll add
some info from Canberra, on the population trends of the species, with
this extract from my "Canberra Birds: A Report on the
first 21 years of the Garden
Bird Survey". (This is based on 1316 observer years of data.) The COG
Atlas (McComas Taylor & COG) tells a similar story.
Fan-tailed Cuckoo Cacomantis
flabelliformis
This is a forest and
woodland inhabitant. It is less migratory than other cuckoos, so its monthly
pattern, although typical of cuckoos, is much less well defined. This species is
quite vocal, especially during spring. However the call is probably not as
far-carrying as Pallid or Brush Cuckoo. From a mid winter low with very few
observations, numbers increase sharply from August to a peak in October, then
decline quickly till December, staying in even reduced numbers through summer
and autumn before declining to the winter low. Numbers have declined
significantly, at about half the abundance from Years 12 to 21 as for the first
11 years.