|
David - I assume you are referring to the bower in
Downes Place? I believe this usually has a lot of yellow Sulphur Crested
Cockatoo crest feathers at one end - I've seen or heard about this from other
local bowers. SBB often use light yellow leaves as well for
decorations.
It is likely that the green birds, or at least some
of them, were young males. These don't acquire their adult plumage until
about 7 years. The easiest way to tell them (4+ years) is by their very
light bills, about the same colour as the mature male, compared with the darker
bills of females and younger birds. I agree they were likely trying
to take bower material or destroy the bower. They are known to learn to
build bowers by watching other males and while they do build practice
bowers (often very rough untidy structures) this particular bower is very
likely the main one in the area. Stealing from or destroying bowers is a
regular pursuit for the SBB. Bowers can be rebuilt very
quickly.
Your observation of a male just starting to moult
into mature plumage is a very interesting one. My previous observations
have been that this happens locally during Feb/March [see CBN 29(1) p 33
(2004)], but I've heard about this also happening over the past couple of
months, something I still need to chase up. It's well worth keeping an eye
on this bower to see if it's happening over a similar time frame as
published.
Jack Holland
| 