Silent migratories

["Greg" <>]

Hi Margaret,

I like to record the departure dates for the local migrants such as the 
cuckoos, Dollarbirds, Sacred Kingfishers etc. as it is interesting and 
important information in light of global warming.  I have had more 
overwintering (or late departure and early returning) Rufous Fantails in the 
Clarence Valley, North Coast New South Wales, in recent years.  Is this a 
response to global warming?
There is one complication that I only considered recently.  Departure dates 
are not necessarily departure dates for the local population but may reflect 
the last date that birds from further south move through a particular area. 
Local birds may have migrated weeks earlier.
Greg Clancy