Declines in common species

To: "Simon Mustoe" <>, "birding aus" <>
Subject: Declines in common species
From: "Philip A. Veerman" <>
Date: Fri, 12 Apr 2002 11:51:52 +1000
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.
-----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.


Simon Mustoe.


Simon Mustoe - Principal

AES Applied Ecology Solutions Pty Ltd.
59 Joan Avenue
Ferntree Gully
Victoria 3156
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