nocturnal migrants

[(John Leonard)]

Tricky question here:

Why do certain noctural birds migrate south in summer (I'm thinking of
White-throated Nightjars and Little Bitterns, there may be other examples)?

Because in doing so these birds are moving into areas where the biological
productivity is likely to be lower, and the nights shorter, at a time when,
as they are breeding, they are in need of more food.

Puzzled

Canberra




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Dr John Leonard
PO Box 243, Woden,
ACT 2606, AUSTRALIA

'That nature which contemns it origin
Cannot be border'd certain in itself'
                                      King Lear


http://spirit.net.au/~jleonard
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