As others have been speculating I too can speculate....
I take the point that heavy and frequent rain leads to problems with
nests and nestlings and probably depresses breeding success.
However, I would have thought that in the long run the abundant of
insect and (later) plant food (seeds &c), will compensate.
This current drought-breaking rain spell is associated with a La Nina
and an Indian Ocean phenomenon whose name escapes at the moment and is
due to last through into 2012. This will cause heavy than average
rainfalls in the ACT but it don't think it will mean downpours with
quite the intensity of the last few weeks over the whole period.
What I think this will mean is that the breeding season this season
(summer 2010-11) will last longer, with birds rearing more broods and
migrants possibly staying longer. The same may happen next season.
In common with other observers I am noticing the absence of 'western'
spp and a general shortage of birds of all kinds (especially smaller
ones). However I assume that this is because what birds there are are
spread more thinly over a wider area (and also that there is more
vegetation for them to conceal themselves in!). I anticipate that by
next season we will see greater numbers of birds overall and as the
next dry period begins the return of western spp in greater numbers.
--
John Leonard
Canberra
Australia
www.jleonard.net
I want to be with the 99,999 other things.
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