CHAPTER 6
POTENTIAL IMPACT OF AVIAN DISEASE ON AUSTRALIAN NATIVE
BIRDS
6.1 Newcastle disease is widely considered to be a significant threat
to the Australian native bird population. Committee members sought information
about why AQIS did not consider it necessary to conduct an environmental
impact study as part of its risk assessment process.
6.2 Mr Digby Gascoine explained that under the Quarantine Act, the Director
of Quarantine is obliged to make decisions in the light of the obligations
imposed by the Environment Protection (Impact of Proposals) Act. Under
this Act, the Minister or the relevant authority must consider whether
an action is an environmentally significant action. An environmentally
significant action is defined as an action which will, or is likely to,
affect the environment to a significant extent or result in such an effect.
6.3 Mr Gascoine said that in AQIS's view, if Newcastle disease entered
the country, the impact on Australian native birds should be regarded
as potentially extremely severe. He continued:
It is on that basis that we have assessed whether or not we think there
would be a significant environmental impact. Our conclusion has been
no, on the basis that we believe that the probability of the disease
entering Australia and becoming established in a wild population is
negligibly low.(1)
6.4 On the basis that the risk of disease entry is low, AQIS has come
to the conclusion that the decision to allow the importation of cooked
chicken meat is not a decision which is likely to affect the environment
to a significant extent. Accordingly, AQIS decided that there is no requirement
to conduct an environmental impact study.(2)
6.5 AQIS officers advised that the Environment Protection Authority was
"totally in support" of AQIS's decision on this matter.(3)
6.6 Mr Gascoine emphasised that the probability of Newcastle disease
entering the native bird population is dependent upon the coincidence
of several events. He said that while AQIS regards the cooking process
as an important part of the overall protocol, the overall probability
that an exotic disease will become established in Australia is obtained
by multiplying together a number of different probabilities. These are:
- the probability of a bird being subject to processing having the disease;
- the probability that the cooking process will fail;
- the probability that that piece of meat which contains a disease and
was inadequately cooked, is discarded;
- the probability that, when it is discarded, it is taken up by a bird
or some other animal, or through some other agency finds its way to
a native population of birds;
- the probability that it then establishes in that population.
6.7 Mr Gascoine concluded:
The point I am trying to make is that the overall risk is assessed
on the basis of a potential chain of circumstances. And that is how
we go about our risk analysis. While each of the individual elements
of that chain may be very important, the overall probability has to
have regard to all of the events which have to occur in order to enable
an exotic disease to establish in Australia. It is that combination
which is, in the end, crucial and not merely one step in that combination.(4)
Committee view
6.8 The Committee is concerned about Mr Gascoyne's propositions concerning
the overall low probability of ND entering the native bird population
if and when cooked chicken meat is allowed into Australia. Although there
is conflicting evidence about how the 1930 and 1932 ND outbreaks occurred,
it is not difficult to envisage scenarios in which scavenging birds could
provide a means for ND to enter the native bird population and the Australian
poultry flock.
6.9 The Committee notes that despite its assessment of the low probability
that disease would be introduced, AQIS saw fit to commission a study by
ABARE of the economic impact of introducing Newcastle disease. Mr Hickey
explained that under the terms of the SPS agreement, Australia is able
to take account of the introduction of the disease.(5)
6.10 The Committee accepts that AQIS's approach to environmental assessment
is consistent with the terms of the EPIP Act. However, from an outsider's
perspective, this approach may seem somewhat inconsistent, as despite
AQIS's assessment that the risk of disease entry is low, it commissioned
an economic impact study.
6.11 The real issue in relation to the possible introduction of NDV or
IBD relates back to the success or otherwise of the heat treatment and
the post treatment packing and handling. Therefore the Committee is of
the view that implementing its recommendations regarding the tests of
heat treatment on chicken meat and the performance of commercial ovens
are the key to the potential risk to native bird life.
Chapter 7
ENDNOTES
- Evidence, 30th September 1996, p. 286.
- Evidence, 28th August 1996, p. 23.
- Evidence, 28th August 1996, p. 33.
- Evidence, 30th September 1996, p. 286.
- Evidence, 28th August 1996, p. 34.