Steve Roderick" <> wrote :
> The first year birds of some species of migratory waders
> over-winter in Australia in small numbers. This has two benefits
> to those species - the young birds build there strength by cutting
> out the migration to the north and back, and the breeding birds
> have less competition at the breeding grounds.
I can agree with the first benefit. The second benefit is harder to agree
with. The numbers on the breeding grounds would reach the current
capacity. This would result in a lower overall population, but the same
numbers on the breeding grounds.
The first year birds of quite a lot of the migratory waders over winter.
For Red-necked Stint and Curlew Sandpiper the results from wader banding
have shown that they mostly return in their second year. However the
larger waders stay longer. Great Knots (and I think Red Knots?) stay in
Australia for two seasons. Bar-tailed Godwits (and I guess Black-tailed
Godwits) usually stay for at least three seasons before they make their
first return. I don't know the results for even larger waders such as
Whimbrel and Eastern Curlew.
And they stay in large numbers as anyone visiting Broome, 80 Mile Beach,
Port Hedland etc in the dry season will attest. Even in July you will
find 15,000+ waders in Roebuck Bay at Broome.
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