this is the best info i have found to state what I see here.Thanks folks. Thought that was the case, but last year they molted (the older ones) going into winter. Perhaps they are confused with this weird weather?
Mature birds normally undergo one complete moult a year, usually in autumn. However, this can depend on the time of the year that the bird started laying. Natural moulting usually begins sometime during March or April and should be completed by July when egg production recommences. The three main factors that bring about moulting are:
- physical exhaustion and fatigue
- completion of the laying cycle (as birds lay eggs for a certain period of time)
- reduction of the day length, resulting in reduced feeding time and consequent loss of body weight.
from here http://www.daff.qld.gov.au/27_2709.htm