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From the 18 years of continuous GBS data in
Canberra, the Goldfinch has shown a decline but that is not easy to interpret.
It is largely based on the fact that it was especially abundant in 1981-82. That
being the first year of the GBS, it is impossible to know whether it was just an
odd year. After 1982-83 it has been basically stable here. Unlike say the
Starling and House Sparrow, whose abundance has crashed over the same period.
Philip
-----Original Message-----
From:
Simon Mustoe <>
To:
<>;
Rory Poulter - Atlas Project <>
Date:
Friday, 12 April 2002 9:02
Subject: [BIRDING-AUS] Declines in
common species
Regarding Rory Poulter's posting on
declines in Goldfinch numbers. This is
quite interesting from a
conservation perspective.
Conservationists often lend great weight to
decines / range contractions in
'rare' species when tackling issues of
national conservation. With the
advent of a more holistic biodiversity
approach, there has been a shift in
parts of the world from looking at
declines instead of absolute numbers as
an indication of 'threat'. So for
example, species that are undergoing a
high rate of decline are likely to
be those that are suffering the greatest
ecological pressure and
therefore require conservation attention. In the UK
publication of the
Red List of threatened birds by the RSPB / BTO in 1996
revealed drastic
declines in many common species.
Being an introduced species, this
does not necessarily translate to
Goldfinch in an Australian conservation
perspective but it does show that
common species - even common introduced
species - may be under the same
conservation pressures as rarer native
species and may be useful indicators.
So rarer species that are the focus
of single-species action plans may be
failing as the result of background
pressures that are better understood by
focusing on more common speciesn
that illustrate a wider problem. How
declines in species like Goldfinch
compares to the few other widespread open
country natives, I don't know.
I would expect a similar trend and it would
be interesting to hear
whether this is the case.
It may be significant that Goldfinch, a
relatively common species in the UK,
has undergone declines in the order
of >25% in the last 25 years. Other
species such as Tree Sparrow have
undergone declines of >90% and are
becoming critically threatened as
populations are seriously fragmented. Most
of the species affected are
farmland birds and the reductions have been
attributed to pesticide use
(herbicide and insecticide) knocking out large
components of the
biosystem on which the food chain depends.
This change in
conservation emphasis is important as it recognises that
pressures are
fundamentally large-scale and that mitigation strategies need
to address
the entire country rather than be species or local area
focused.
Unfortunately this approach requires considerable intervention
by the
government and a regulatory / incentive based system that can
redress long
term problems and reverse existing trends away from an
ecologically
non-sustainable system. All the existing livelihoods that
depend on an
economy that has grown in the wrong direction cannot carry
the financial
burden of long-term misintervention by the government,
which is why
subsidies may be required. This isn't really anyone's fault,
it's a fact of
life perhaps that our knowledge improves as we pay better
attention to these
matters. But it needs to be recognised as soon as
possible or the reversal
options will become more difficult and
expensive.
That puts it in a nutshell anyway. Feel free to object to
this hypothesis.
The pressures in the UK are fundamentally agricultural
(over 70% of the land
surface area is farmland) and there is an
increasing understanding of how
intensification of farming has put undue
pressure on the ecology of the
country. For example, there are other
concerns also - land drainage has not
only conservation implications but
also social ones, resulting in flash
flooding in some areas. As a result,
the government and the Royal Society
for the Protection of Birds (RSPB)
have for a number of years been
developing strategies to buy back
floodplains and return them to their
former extent.
The Australian
situation is different in many ways but the principles are
the same.
Perhaps it is also significant to add that a recent mandate
in
legislation has meant that farmers in the UK have to enter into
management
agreements to protect Sites of Special Scientific Interest -
areas that were
designated as important when the Wildlife and Countryside
Act was first
introduced about 30 years ago. Since then, many of these
sites have fallen
into disrepair, many have been destroyed and most have
lost the feature that
they were originally established to protect. The
government has learnt that
self-regulation and passive protection does
not work. It has taken 30 years
to make this enormous leap in legislation
and it remains to be seen how it
will be managed and whether it will be
wholly effective or not.
I would be very interested to hear more
sneak previews of the atlas results.
All of what I have been talking
about above came about after the second BTO
Breeding Bird Atlas for
Britain and Northern Ireland.
Regards,
Simon
Mustoe.
_____________________________________________
Simon
Mustoe - Principal
AES Applied Ecology Solutions Pty Ltd.
59 Joan
Avenue
Ferntree Gully
Melbourne
Victoria
3156
AUSTRALIA
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