Hi Greg & Wynton,
Thanks for your replies regarding grey butcherbirds. So far the two year
girl is still around, and the two girls from a larger family nearby are also
still with their family group. They get a bit harder to keep track of at two
years old, as their plumage looks a lot more adult-like. But they will still
beg for food in adult company, and the white areas of their plumage tend to
be buff-grey rather than stark white.
Greg, regarding sexing juvenile grey butcherbirrds, I only have anectodal
observations based on knowing certain families over many years , as the
books I have don't really say anything specific on this subject. What we've
noticed is that the males lose the `brown/fawn' colouring by 3 months of
age, and start to look more like adults. The females will remain a
distinctive light brown colour until about 15 months of age, and then take
on the `black white and grey' adult plumage after a couple of months of
really strange-looking hybrid colouring. I sometimes wonder if this is
nature's way of preventing the females from being courted before they are
sexually mature?
There are some marked behavioural differences between male and female birds-
pied & grey- as well as magpies and other birds too. I wonder if others have
noticed this? Around people they know, the males are rather relaxed and very
forward, whereas the females are shier and get worked up easily over things.
This is more pronounced when they are immature. For example male grey
butcherbirds can be overly relaxed and forward, and they have a high
motality rate. The females tend be especially shy, angry, and stealthy.
Regards,
Belinda
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