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Philip,
Your "absolutely nil bearing" is drawing a
long bow.
If you eliminate the vagrants from the count, which let's say
is 10, then the figure must provide some sort of indication of the rate of
decline or growth. In other words, if a species in the count can be verified to
be newly present at a certain season under certain weather, migratory or
other species-specific conditions, then I would take that as fair and reasonable
indication that the species is on the up and up in the Sydney
region.
If for example (and I don't know if these are in the count),
the extant Sydney glossy black cockatoo population from Beecroft-Hawkesbury
takes a turn for the better, then one might expect that to eventually be added
to the non-vagrant count somewhere at Royal NP.
Regards
-----Original Message-----
From:
Philip A. Veerman <>
To:
Vella <>; birding
aus <>
Date:
Friday, 25 May 2001 11:57
Subject: [BIRDING-AUS] Royal
National Park
Whether or not "Sydney's Royal National
Park has around 279 species" has absolutely nil bearing on the
suggestion (which I strongly suspect is an urban myth, based on nil
evidence) that our birdlife is on the decline in Australia's largest city.
(No doubt some species have declined, others increased, others constantly
change up and down.) Number of species that have been recorded in an area is
irrevelant to an assessment of change to population levels of many species.
Anyway, where are the long-term detailed population studies of Sydney's
birds? No-one at my 28-4-2001 talk to SNAG in Sydney, about COG's GBS said
anything like "we have something like this in
Sydney"!
-----Original
Message-----
From: Vella <>
To:
<>
Date:
Wednesday, 23 May 2001 18:48
Subject: [BIRDING-AUS] Royal
National Park
It has been boasted on the radio today (on
Sydney's newest radio station Nova 96.9), that despite the thought of
many people thinking that our birdlife is on the decline in Australia's
largest city, bird watchers can be happy to find that Sydney's
Royal National Park has around 279 species.
I have not yet obtained Steve's new book on
the Royal NP, which mentions the 279 species. I suppose this number of
species may include some vagrants! Can anyone comment?
I have made a list of birds in my local
shire - Blacktown shire and have currently a list of 206 species
(over 90 percent would have been seen in the last 10 years. Has anybody
else made a list of the birds of their own shire/local
area?.
Edwin Vella
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