On 09/05/2011 12:08 AM, wrote:
extremely agitated. The source of the agitation was a lone Tawny Frogmouth
trying to catch a few ZZZZs.
and
The Frogmouth was perched on a relatively thin branch in a Willow Myrtle
and didn't look at all like the usual broken branch stub. The Butcherbirds
A couple of points arise from this. Firstly, I have never seen any
evidence of Frogmouths sleeping. As far as I can tell, they are always
awake and alert. I have watched them under a great variety of
circumstances both in the wild and in captivity, and I have never seen
one which seemed asleep.
I have seen plenty of other birds which appeared to be asleep and were
clearly unaware of things going on around them. But I don't know what
sleep means to a bird, and if there is a range of states which they can
be in, or how different groups of birds vary in this respect.
The second point is that the usual stance of a resting Frogmouth during
the day is just what it is at night, with the bird perched on a branch
in a relaxed pose which doesn't differ profoundly from what other birds
do. The "broken branch" pose is what they do when they are on the alert
to a perceived threat. If you watch a resting Frogmouth from a distance,
you can see it strike that pose when a hawk flies by, or a person walks
near the bird. Once the threat is past, the Frogmouth relaxes again.
As an aside, decades ago Jack Pettigrew explained how Frogmouths have
two different kinds of vision, resulting from swiveling the eyeballs in
their sockets so they can either have a very wide field of vision with
limited overlap between eyes, or they can look forwards with binocular
vision. If you walk around a Frogmouth in its broken branch pose, you
can often see this distinction, as the bird will follow you with one eye
and will subtly turn its head to keep you in view with just one eye
through a narrow slit. Then at some point, it will suddenly turn to face
you and look straight at you with both eyes forward, giving an Owly look.
Frogmouths are great birds!
Cheers, Chris.
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