Could be a number of reasons but I would probably suggest that the bird is no longer able to breed and might be using your local ponds as a retirement village in its twilight years.
I would have thought that the urge to breed would have sent it looking for suitable partners a long time ago.
Paul Randall (wingsonwire.com) ===============================
To unsubscribe from this mailing list, send the message: unsubscribe (in the body of the message, with no Subject line) to: birding-aus-request@vicnet.net.au
http://birding-aus.org ===============================