I recommend that the answer to all these style of questions is: “because
their parents did”. In other words, it is something in their genetic makeup and
you can apply that, to most zoology questions of that style. It is something that
has been done and survived well in their evolutionary history, giving some
benefit. Indeed likely going back to whatever species the magpie was, before it
was the current species. Evidenced in that the behaviour is something occurring
in many birds, so is in the genetic makeup of many birds. As to what is the
adaptive advantage of them singing at night now, well that is a different
question and there are many possible answers. But easy to simply suggest that
it is territorial behaviour, exactly as it is in the daytime (and why wouldn’t
it be?), allowing the magpie individuals to signal to neighbouring groups that
they are in the area, or whatever other message it sends. Sending vocal signals
may well be more effective at night, as there are normally less competing
sounds around.
Philip
From: Birding-Aus
[ On Behalf Of Peter Shute
Sent: Monday, 26 September, 2022 5:20 PM
To: Birding-aus NEW
Subject: [Birding-Aus] Magpies singing at night
I have been asked to post this question:
'I gave a talk at my local
library on Bird Watching. I was asked 'Why do Magpies sing at
night?' I did not know. Does anyone know?