On Tue, Feb 14, 2012 at 01:36:44PM +1100, Simon Mustoe wrote:
> Point taken. You are absolutely right, no-one can ever be absolutely
> certain of the population of any bird. Not entirely sure how much the
> difference between 21 & 35 exaggerated the plight though - can do you
> really think that's an excuse for what the media and politicians are
> doing? Perhaps I am missing something.
Bird-o says this season has been disaster for OBPs with their population
dropping 40%. But the OBP people seem to be saying there has been no
change in the number of Melaleuca adults from last year.
Bird-o says 21 OBPs left in wild, the OBP people seems to be saying
40-ish - at least 31 at Melaleuca plus maybe some elsewhere.
Bird-o sprays journalists for inaccuracy and use of secondary sources
but seems itself to ignore what the OBP people are saying.
Looking at estimated OBP survival rates I think you would expect only
~15 adults to have made it back to Melaleuca this year, so 21 looks like
a good result. And if you assume some of the 21 juveniles captured last
year would have made it back as adults, there might have been a decent %
increase in Melaleuca adults except for the captive breeding intake.
On the ABC Mark Holdsworth talks about the drought hurting OBPs - so
maybe this reflects wetter La Nina conditions. Of course the number of
OBPs leaving Melaleuca this year is the next big question.
Also as an aside I think you might have Saltmarsh Sparrow range confused -
only the occasional wintering bird makes it to Louisiana.
Incidentally the media pieces didn't look that bad to me. Sid Maher's
piece had an unsympathetic slant but much better than some of the rabid
anti-science found in the Australian. Ten News isn't Four Corners,
but they showed a few interviews and many viewers would have found
the young researcher from Healesville more convincing than Greg Hunt's
abysmal sound bite.
Andrew
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