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From 1980-1994 total imports of grains, pulses, oilseeds and oilseed meal have been approximately 1.3 million tonnes (Grain Statistics 1994). However, due to the recent drought there has been a significant increase in the volume of bulk grain imported, maize and sorghum specifically, for the feedlot industry. This pattern of higher bulk grain imports appears likely to become the norm as the feedlot industry seeks the cheapest sources of grain. With these imports comes the risk of weed seeds, plant pathogens and insect pests entering Australia. One important risk from these imports is the possible introduction of two serious insect pests of stored products, as well as strains of other stored product insects already in Australia that are resistant to the fumigant phosphine. The Khapra beetle, Trogoderma granarium (Coleoptera:Dermestidae) has a well established reputation as a quarantine risk and is the subject of vigilant inspection. The larger grain borer, Prostephanus truncatus (Coleoptera:
Bostrychidae) is less well known. Once apparently restricted to
Mexico, parts of Central America and the extreme south of the
USA, it has now become established in Africa, as a result of at
least two separate accidental introductions; one into Tanzania
and the other into Togo. In both regions it quickly became a major
pest of farm-stored maize (especially cob maize). Now it is becoming
widely distributed in sub-Saharan Africa. One of the most important
aspects of the biology of P. truncatus in the Americas
is that it is found living away from maize production areas in
natural habitats in Mexico, and in a wide range of bush and forest
habitats in Honduras. In Kenya it has been shown to be capable
of breeding in several species of savanna trees, and there are
indications that it could survive and disperse in the Australian
acacias (D. Rees, pers. comm.). In addition P. truncatus has been shown to be a very mobile insect, capable of flying many
kilometres, and more cold tolerant than the lesser grain
borer, Rhyzopertha dominica.
Actions that can be taken to prevent introductions of insect pests
of stored grains include
The latest version of the AQIS standard for fumigation with methyl
bromide has been severely criticised by an executive of a multinational
pest control business (see Section 5.4). It has been suggested
that the standard makes no provisions for fumigators who undertake
cut price jobs at prices below that necessary for the correct
dose of fumigant required for the job. Such practices occur in
South East Asia, where Quarantine Officers have, off the record,
openly admitted that this practice occurs and their inability
to control it. Very little reliability can be placed on fumigation
certificates accompanying some imports, and there is a need for
more rigorous inspection of commodities on arrival in Australia.
Sampling and pre-shipment fumigation should be directly supervised
by AQIS inspectors, by temporarily positioning inspectors in exporting
countries for the duration of a 'season'. Such supervision
should not preclude further inspection on arrival in Australia.
This practice is commonly applied by Japanese inspectors positioned
in Australia for the duration of the mango and orange seasons.
The recent identification of methyl bromide as a serious depletor
of the ozone layer and its toxic effects on mammals has jeopardised
the future of a very useful fumigant. Presently, the phase out
proposals specifically exclude pre-shipment and quarantine applications
of methyl bromide. However, it is likely that these applications
will also be phased out. Thus it is important to ensure the availability
of phosphine as a fumigant because it is the only suitable 'plug-in'
replacement for methyl bromide.
Recommendation 3.1.1.1
The Review Committee is encouraged to consult stored grain
experts to assist in assessing the risks of pests and diseases
entering Australia with bulk grain imports and to determine procedures
that will facilitate these importations, while reducing the risk
of unwanted incursions to an acceptable level.
Imports of germplasm, in the form of seed material, are significantly
less in volume than those of bulk grain but the frequency of seed
imports is likely to increase with the effort to diversify and
improve Australian seed crops, especially grain legumes; this
will increase the risk of introducing new pests.
Notionally, all such seed introductions are rigorously inspected
for the presence of both pathogens and insect pests. However,
where such introductions are made from the Consultative Group
for International Agricultural Research (CGIAR) and other international
organisations, no assumptions based on experience of earlier introductions,
should be made concerning their pest freedom. There is also a
concern about the use of methyl bromide (see above) and alternative
methods may affect the viability of the seed. A particular concern
is the risk of entry of bruchids, which are, weevil pests of legumes.
At present the only bruchid of importance in Australia is Bruchus
pisorum, the pea weevil. Effective control of this pest requires
a specific fumigation regime, with a high phosphine dose. Similar
requirements may be necessary for any new bruchid pests introduced
to this country. Incursions of species presently unknown in Australia
could adversely affect current storage practices for these commodities
and jeopardise strategies for agricultural expansion into legume
crops new to Australia.
While there is a requirement for mandatory disinfestation of species
of annual Trifolium brought into Australia and farmers
are permitted to import up to 50 kg of seed without quarantine
inspection, the decision is based on a visual inspection. This
is of dubious value if the seed has been recently infested. Similarly,
lentils are not subject to inspection.
Two recent examples illustrate the potential risk in these policies.
In one, a scientist working in Western Australia insisted that
samples sent to him be disinfested with phosphine and subsequent
examination of the material revealed evidence of bruchid infestation.
In the second, concern was expressed (pers. comm., Darryl Hardie)
about a consignment of legume seeds that was carried into Australia,
declared and passed by the AQIS inspectors on duty at the airport
concerned. Subsequently, a number of insects, tentatively identified
as Bruchus affinis, lesser pea weevil, emerged from the
material. This insect is a potentially serious pest of legumes.
At present, however, there is no specific AQIS requirement to
inspect or disinfest any legume seed for bruchids, except for
the mandatory fumigation requirement for medic seed from the Mediterranean
region. Currently, only fumigation with methyl bromide is permitted.
However, this treatment is known to adversely affect germination.
An alternative treatment that will also kill pathogens is required.
It has been suggested that heat treatment provides a possibility.
Much of the work on thermal disinfestation has been undertaken
by the CSIRO Stored Grain Research Laboratory and it is possible
that the laboratory-scale rigs developed for this work could be
developed to handle small volumes of seeds.
Recommendation 3.1.2.1
AQIS should reform the quarantine requirements for the import
of legume seed and establish fumigation procedures that are effective
and do not affect the viability of the seed. 3.2 Deliberate introductions of plant material for pasture
improvement and horticulture
A number of the plant species, which are now recognised as pests,
entered Australia as ornamental plants and were first cultivated
in Botanical Gardens. Examples are Mimosa pigra that lived
in the Darwin Gardens for many years before escaping to become
a major pest in Northern Australia; likewise, Lantanaand
Patterson's curse, came as ornamental plants. The North American
prickly pear (Opuntia spp.) was introduced both as an ornamental
and as a paddock hedge. These cases could be considered to be
unforseen disasters, but more serious in its implications was
the program, from 1947 to 1985 to introduce grasses and legumes
to tropical Australia to improve the nutritional quality of pastures
for beef production. The purpose in the view of those funding
this work was no doubt laudable but, the outcome, as Lonsdale
shows (Australian Journal of Ecology 19, 345-54, 1994),
was a serious disregard for the long term effects of introducing
alien plant species. Again, there was no legal impediment to their
importation, nor their incidental release into the environment,
once they were discarded as useless for pasture improvement. During
that period 463 species in 2033 accessions were introduced, the
grasses mainly from Africa, the legumes mainly from Central and
South America. There was no screening for potential adverse effects
of the plants before trial, nor was there any attempt at containment
of these species during or after evaluation. Of all these species
only 21 have proved to be useful to the cattle industry, while
60 other species have become recognised as weeds, 13 of them being
listed as major weeds. Of these species 21 are weeds of cropping,
20 are weeds of conservation and the remainder weeds of both cropping
and conservation. The annual rate of production of the cattle
industry in the Northern Territory is $1.48/ha, while the cost
of weed control is $30/ha for annuals and $129/ha for perennials.
In this important instance, the environmental externalities had
not been considered, and it required the individual effort of
a plant ecologist to draw attention to an unsatisfactory situation.
Because the benefit to the cattle industry was perceived as a
national good, Australia must now continue to pay a huge and continuing
cost for these introductions.
Recommendation 3.2.1
Before permission is granted for import of any potential
pasture plant it should be investigated for its potential weediness
(which often makes it an attractive pasture plant) by a broadly
based committee that will consider environmental impacts, as well
as potential benefits for agriculture.
Kochia scoparia, a roly-poly type plant was introduced
into WA in 1990 to stabilise salinised land. At that timeKochia was not listed in the schedules of Proclamation 86P and there
was no legal impediment to its importation. It is now listed as
a noxious weed.
Siam weed, or Chromolaena odorata, a major tropical weed
species,Chromoleana odorata was first discovered in Queensland in 1995 by
a NAQS officer while on holidays. The weed had been in the country
for some years and was well established. The area of infestation
was just south of NAQS's region of responsibility and, on this
technicality, it was difficult for the officer, who detected the
infestation, to elicit effective action by or through NAQS. In
this case, pre-emptive declaration of Chromolaena as a
noxious weed by the Queensland Department of Lands, facilitated
an immediate response to the weed.
Seeds of weed species, likeKochia andChromolaena,
can be transported unwittingly by travellers and establish in
remote areas before detection, making eradication difficult or
impractical. N.M. Wace (in Pests and Parasites as Migrants,
pp 3-32, 1985) gives figures for 305 seeds of 37 species germinated
from the clothing of 12 tourists, who had recently arrived in
Australia from 10 different parts of the world. This shows how
great is the magnitude of this, inadvertent, route of entry for
unwanted plant species.
Another newly detected plant, which appears set to become a major
weed, is the South American Praxelis clematidea (Asteraceae),
previously unknown, but found to be common during the survey for Chromolaena. It has since been recorded over a very wide
area and is thriving as a weed of roadsides, river banks etc.
It is also known in Hong Kong and other parts of southern China
where it is spreading rapidly. This is an example of a plant species
which is unlikely ever to be placed on an AQIS target list, (even
though it belongs to the very weedy supertribeEupatoriae) becoming a serious threat when transferred to Australia.
Australia is so large and bioclimatically diverse that it would
be difficult to arrive at a list of plant species that might become
invasive in unmanaged Australian environments if imported. Nevertheless,
a list could be compiled of those species that are known to be
invasive elsewhere, along the lines of the US Department of Agriculture
Handbook No. 498, entitled Economically Important Foreign Weeds
- Potential Problems in the United States(1977), and Alien
Plant Invasion in Native Ecosystems of Hawaii, published by
the University of Hawaii in 1992.
Recommendation 3.2.2
The Review Committee should explore the linkages between
AQIS, ANCA and DEST, to ensure that environmental concerns of
exotic weeds and pests are addressed in Australia's best interests.
3.3 Cut flowers and ornamentals
The Australian cut flower and the ornamental industries are involved
in both export and import of flowers and plant cuttings. Imports
into Australia consist mainly of ornamentals and propagative or
seed stock.
There has been a dramatic increase in the amount of living plant
material entering Australia on a daily basis over the past decade,
especially cut flowers. Figures indicate that the number of consignments
of cut flowers entering Australia during the period 1993-1995
through Mascot airport has remained steady at approximately 800
per year. There has however, been a significant increase in the
size of these consignments. The international airport at Perth
receives around 10,000 separate cartons of plant material each
year. The actual figures between 1988 and 1994 range from 9,400
to 14,165 cartons.
This route of entry for exotic plant pests and diseases undoubtedly
represents the greatest opportunity for quarantine failures for
Australia. This can be discerned by examination of the AQIS listing
of pest interceptions, in which nearly half the interceptions
are made from imported cut flowers.
The threat posed by cut flowers stems from a number of reasons:
There is good evidence that the whitefly,Bemisca tabaci,
(biotype B) entered Australia on cuttings of Poinsettia from California, and the Western flower thrips, Frankliniella
occidentalis, may have entered Australia from Zimbabwe on
imported cut flowers (pers. comm. J. van Someren Graver, CSIRO,
1995). Both insects have wide host ranges and, more seriously,
are vectors for plant viruses capable of infecting both native
and cultivated plants. Thus because of inadequate control of entry,
one relatively small industry has been responsible for a problem
of national importance and great potential cost. Recent studies
indicate that the whitefly is regarded as the most important insect
pest of agriculture in the USA since 1991. It is estimated that
in the Imperial Valley of California from 1991 to the end of 1994,
9,000 local jobs had disappeared and crop losses dues to this
pest exceeded $300 million.
It is alleged, in the case of one introduction, that inspections
undertaken on entry to Australia did not include searches for
this pest 'because it was not known to be in the country
of origin'. In another case it is alleged that the consignee,
when told that a consignment had to be disinfested with methyl
bromide, persuaded the inspector to use another treatment less
injurious to the plant 'because methyl bromide damages the
plants'. It appears that there has been a failure to communicate
to the inspectorate the precise location details of some rapidly
dispersing insect pests that are known to pose a quarantine risk
to Australia; and a lack of rigour in the application of prescribed
quarantine disinfestation treatments.
There is also a likelihood that some of the established disinfestation
procedures may fail to completely control infestations. This view
was expressed by R. Roush (Waite Institute) some years before
the whitefly entered Australia. Treatments may be applied after
detection of infestation by insect pests and the material released,
without further inspection.
For example, two principal markets for Australian cut flowers
are Japan and the USA, both of which apply stringent quarantine
controls to prevent importation of living insects. There are reports
from exporters, who have had consignments of cut flowers fumigated
in accordance with established AQIS protocols before shipment,
that such consignments have had to be retreated after living insects
were detected in them by Quarantine Inspectors on arrival at the
port of destination (J. van Someren Graver, pers. comm.).
The Academy does not suggest that the amount of living plant material
entering Australia should be reduced. However, it does argue that
adequate and effective protocols should exist and be implemented
rigorously.
Recommendation 3.3.1
The Academy recommends that cut flowers be subject to mandatory
rigorous treatment schedules based on a systems approach of decremental
pest control measures from field to preshipment disinfestation,
in order to reduce the infestation load on transported material.
AQIS inspectors should be posted to countries from which cut flowers
are imported to ensure that any such treatments are adhered to.
Recommendation 3.3.2
The Academy recommends that AQIS identifies gaps in knowledge
and commissions research to underpin the development of effective
protocols so that trade opportunities are fully exploited for
cut flowers and ornamentals, but not at an unacceptable level
of risk of quarantine failures. These protocols should be enforced
without exception.
3.4 Ballast water from, and hull biofouling of bulk ore and
woodchip carriers
Several marine organisms from the northern hemisphere have established
themselves in Australian coastal waters in recent years and are
said to be displacing indigenous species. The Centre for Research
on Introduced Marine Pests (CRIMP) was set up in 1995 to develop
methods for the early detection of marine pests, and to develop
new methods to control the spread and minimise the impact of introduced
marine pests. One likely route by which the organisms enter Australian
waters is in the huge volumes of ballast water that are discharged
by bulk ore and woodchip carriers on arrival in Australian ports,
preparatory to loading cargo. AQIS is responsible for controlling
the discharge of ballast water and approving the entry of ships
into Australian ports and it will be taking advice from CRIMP
on means to prevent the survival of foreign marine organisms in
ballast water.
The second possible route is on the hulls of ships, even those
that are well maintained with anti-fouling protection. There are
sites on the hulls of most ships, such as rudder and propellor
housings, bilge tanks and inlet ports, where colonial or aggregating
marine organisms can become established (S.F. Rainer, CRIMP Technical
Report 1, 1995) and then provide harbour for other species, even
including small fish. Thus the ecological risk posed by biofouling
on ships' hulls is not a function of area and, indeed may not
affect the efficiency of the vessel. The species that have been
observed on the hulls of bulk ore carriers appeared to vary with
the port of origin and to include coastal species rather than
open ocean species. Clearly, it is important to determine whether
ballast water or the hull are the main route of carriage of potential
pest species.
In Australia 6-10 million ornamental fish are imported each year
for the aquarium market (J.D. Humphrey, Australian Quarantine
Policies and Practices for Aquatic Animals and their Products;
a review for the scientific working party on aquatic animal quarantine, Bureau of Rural Sciences, 1995). Freshwater species must be held
in quarantine for two weeks but marine species do not require
even this minimum surveillance, and none of these imports require
prior veterinary inspection before release. There are two hazards;
escape of the species itself and the potential pathogens that
it may harbour.
Most of these species would not survive outside the controlled
environment of the aquarium, but some may be able to do so; no
assessment of their long term effects in Australian waterways
is made before each introduction. In the case of tropical species
many are imported direct from the wild in South America or South-east
Asia (W. Laurance, Search, 26, 300-303, 1995). A few years
ago a large National Aquarium was set up in Canberra without consideration
to the possible effects on the Murrumbidgee-Murray river system.
At present in Australia the common carp is spreading at an increasing
rate through the inland waterways, fouling the water and displacing
native species. In 1995 it was discovered in some of the river
systems of Tasmania and the likelihood is that it is being deliberately
put into those rivers. Now the CRC for Freshwater Ecology has
begun a program for the biological control of the carp; the task
is immense.
The second risk of introducing foreign species of fish are pathogens
that they carry, which may affect native species of fish and amphibia.
Humphrey (1995) lists 42 exotic pathogens that have been identified
in ornamental fish imported into Australia, some of which have
become established in native species. Drawing on this evidence
Laurance (1995) suggests that the spreading decline of many species
of tropical amphibia in Queensland since the late 1970s may be
due to one or more such pathogens, which are exotic to Queensland
rainforests.
While human activity is implicated in the entry of most exotic
pests and diseases into Australia, natural phenomena have been
responsible for some significant incursions. For example, the
leucaena psyllid incursion (c. 1980) most likely reached northern
Australia during cyclonic weather. There is also a heavy traffic
of small invertebrates and fungal spores in upper atmospheric
jet streams. A further example is provided by the recent
discovery in Darwin, NT, during a one week investigation by visiting
scientist, Dr Laurence Mound, of several species of thrips known
previously only from Indonesia. Numerous questions remain unresolved;
do they represent recent arrivals, how did they get here, what
is their ability to survive in their new environment. Even their
presence in Australian would have remained unknown, had it not
been for the fortuitous presence of an overseas taxonomist, with
a special interest in this group.
While little can be done directly to reduce this 'natural biotic
traffic', certain indirect measures can be taken to lower the
risk; and more effort could be directed to risk assessment and
contingency planning to cope with anticipated arrivals of undesirable
species (see Section 5). Strong flyers such as the banana skipper
and disease-bearing Asian honeybee species could island hop and
enter Australia by their own efforts. In the latter case, better
appreciation of the risks can sometimes suggest pre-emptive actions
in the common interests of Australia and neighbouring countries.
For example, collaborative research between Australia and its
neighbours, funded by ACIAR and AusAID on biological control has
reduced the abundance of pests like banana skipper and various
bee diseases in PNG. Similar examples of biocontrol of other pests
in the Pacific Islands have worked towards the common interests
of these nations and reduced the risk of incursions into Australia.
3.7 Movement of indigenous peoples in Northern Australia.
The northern borders of Australia include islands only a few kilometres
from the mainland of PNG. These islands are part of a chain of
islands that spans the Torres Strait from PNG to Cape York. The
movement of people, goods and livestock amongst these islands
provide opportunity for the transport of exotic pests into Australia
from PNG and vice versa.
These activities are permitted under the Torres Strait Treaty
(ratified in 1985) which acknowledges traditional customary rights
of the inhabitants. Many in the Torres Strait communities are
aware of the quarantine risks through the education and extension
activities of NAQS.
Recommendation 3.7.1
The Academy recommends that NAQS be given adequate resources
so that field officers are well placed to ensure sound quarantine
is maintained in the Torres Strait.
Many unwanted pests and diseases enter Australia with returning
travellers, either on their persons, in the luggage as incidental
hitchhikers or during attempts to import prohibited materials
. Australian quarantine has always maintained a high profile with
the travelling public and is well respected for its efforts. Its
reputation for protecting Australia against the entry of exotic
pests is well deserved. This aspect of AQIS' operation and the
need for increased awareness by returning Australians and tourists
is dealt with under Section 5.1.
3.9 Deliberate introductions for research
Research material in the form of live specimens including insect,
plant material and seeds, fungal and viral material enters Australia
after a permit has been raised through AQIS. Universities, other
research institutions and some CSIRO Divisions generally use State
Quarantine Services for these introductions. A number of CSIRO
Divisions use the Plant Introduction and Quarantine Service within
the Division of Plant Industry in Canberra. This Unit operates
under a Quality Assurance agreement with AQIS and provides an
efficient service for a number of clients importing biologicals
for research purposes. The CSIRO officer in charge of this Unit
is an accredited Quarantine Officer and this factor is important
in facilitating the importation of research materials while at
the same time ensuring that strict quarantine protocols are followed.
There are numerous advantages in having a Quarantine Officer familiar
with research requirements associated with a research institution.
Apart from being able to facilitate the release of material for
research purposes, the presence of such an officer raises the
level of consciousness of quarantine requirements within a research
institution. With the increasing traffic of material (plasmids
etc.) used in genetic engineering research there is a need to
exercise greater vigilance in this area. The potential for breach
of quarantine regulations is increased by the small amounts of
material involved. The CSIRO Quarantine Officer is confident of
interception of all quarantinable material coming into CSIRO in
Canberra. This is particularly important because of the significant
amount of material that is missed at the international mail exchange
in Sydney.
Recommendation 3.9.1
Given the increasing volume of biological research material
entering Australia, AQIS should consider the appointment of a
specialist Quarantine Officer, along the lines of the CSIRO Canberra
model, in each of the capital cities in Australia. This officer
would be associated with a research institution and act as a focal
point for the clearing of imported biological research material
for all research institutions in that city. Such an arrangement
would have significant benefits both in enforcing quarantine regulations
and facilitating the timely delivery of material for research.
3.10 Deliberate introductions for biological control
Australia as an island nation has enjoyed freedom from many pests
and diseases endemic to other countries. However, the flipside
of this fortunate situation is Australia's high vulnerability
to ecological, economic and environmental impacts when pests enter
the country without the restraining influence of the biotic factors
which might restrain the pest in its natural domain. The identification
and introduction of specific and effective natural enemies to
exert a measure of biological control has been a hallmark of research
in CSIRO and all relevant State Departments in Australia. Australia
is recognised around the world as a leader in this field because
of its impressive record in safe and successful introductions.
Australia has been a pioneer in many areas of biological control,
e.g. being the first country to use fungal species to control
weeds such as skeleton weed. AQIS, together with the EPA, provides
approval for the importation and release of biological control
agents, once specificity and safety has been demonstrated. In
reaching its decision, AQIS and the EPA rely on the technical
advice of CSIRO and the relevant State Departments, following
an evaluation of the evidence supplied by the importing research
organisation. In the past, these arrangements have been entirely
satisfactory and have been conducted in a spirit of cooperation
and collaboration. However, with the recent downsizing of AQIS,
a considerable loss of technical expertise occurred and, in the
view of some collaborating institutions, there exists a real danger
that AQIS is compromising its capacity to maintain its leadership
role in supervising the importation of biological control agents.
A separation of operational and policy responsibilities and the
early retirement of senior technical staff in AQIS has been a
cause of real concern to biological control practitioners.
Recommendation 3.10.1
The Academy acknowledges the leadership role of AQIS in
the safe and efficient importation of natural enemies for biological
control of weeds and pests and recommends that measures be taken
to ensure AQIS is able to maintain this role.
3.11 Genetically modified organisms (GMO's) and quarantine
Under the Convention on Biological Diversity, Australia is engaged
in consultations on a possible protocol on biosafety of GMOs.
This is led by the Department of Foreign Affairs and Trade in
consultation with other government departments and NGOs. At the
most recent meeting held in Madrid during 24-28 July 1995, delegates
from the majority of the countries favoured a legally binding
instrument (a Protocol) on biosafety. However, Australia and some
other countries had not developed a firm position at that time.
Whether or not a Protocol is agreed upon, the movement of GMOs
between countries is certain to become an important issue and
one requiring regulation. Whether this should entail legislation
separate from that already in place for the movement of organisms
other than GMOs is debatable. For instance, New Zealand has adopted
the stance that the same legislation should apply to the movement
of all living organisms, be they naturally occurring species,
those developed by conventional breeding or those resulting from
recombinant gene technology. There is much to commend this approach.
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