What is biosecurity?
The spread of Avian Influenza is a biosecurity
threat to Australia: red countries have had birds killed by the
virus, brown countries have also had hu8man deaths. Source
Biosecurity includes the strategies and methods employed to
assess and manage the risk of introduction of infectious diseases,
genetically modified organisms and pests into an area, including
protection against bioterrorism threats. Biosecurity measures may
include legislation, statutory agreements with neighbouring
countries, surveillance, monitoring, quarantine and border
Why protect Australia’s biosecurity?
Many natural features of the savannas are
relatively recent arrivals such as these Boab trees photo: Ian
There is nothing intrinsically alarming about organisms moving
to Australia, as many of our native animals and plants came from
somewhere else and “moved in”, as did we. However, most
of these organisms arrived piecemeal over long stretches of time
and while many had an initial impact the local ecosystems appear to
have had time to adapt to these new arrivals. Even in the case of
humans, who may have had major impacts when they first arrived, the
local ecosystems have adapted and flourished for tens of thousands
of years after their arrival. The problem today is the sheer
number of new organisms now entering Australia in a very short
In the last 200 years Australia has seen the entry of more than
2800 foreign plants, many of which have become weeds, hundreds of
invasive animal species and many introduced diseases spread by
organisms like fungi, and bacteria. Around 20 new pests or diseases
enter Australia each year. Abundant evidence suggests our
environments are being transformed by this invasion: 22 species of
mammals have gone extinct with foxes, cats and rabbits heavily
implicated in their demise; several endangered mammals now only
survive on offshore islands where they are protected from predators
like foxes and cats; weeds have degraded many millions of hectares
of grazing and natural lands and have caused declines in many
native plant species; disease caused by chytrid fungus is believed
to be responsible for the extinction of seven frog species.
Beer is made from hops, Humulus lupulus, an introduced plant
Of course, this recent wave of new species has also been
responsible for many of the things we value most: wheat, wool and
beef have been important mainstays of the economy; beer, wine,
bread, dairy products, fruit and vegetables are virtually all from
introduced species; and last but not least, non-indigenous people,
and most of their pets and many of their garden plants are all
Feral Pigs and the Dangers of Disease
Feral pigs can harbour or spread exotic diseases, the most
serious of which are: Foot-and-mouth disease which can also affect
cattle, sheep, goats and deer; Swine vesicular disease; African
swine fever and Classical swine fever. These are all diseases that
can affect domestic pigs. Aujeszky’s herpes virus and
Trichinosus are also diseases that are mostly likely to impact on
domestic pigs. Foot-and-Mouth Disease in particular could have
disastrous consequences for Australian agriculture with estimated
immediate loss of $6 Billion in export trade, plus $8 Billion for
every day the outbreak lasted.
Feral pigs can carry more serious diseases than most animal
pests, partly because they have a 10,000 year history of being
domesticated farm yard animals, kept in groups. Jared Diamond in
his book Guns, Germs and Steel points out that being held in
groups along with other livestock like cattle led to the evolution
of microbes that benefitted from this arrangement becoming diseases
of livestock that could spread between cattle, sheep, goats and
pigs as well as related wild species.
Indigenous Rangers taking blood samples from
feral pigs to check for disease
A key to preventing an outbreak of an exotic disease from feral
pig populations is continual monitoring for the presence of such
diseases in the pigs. This is no easy task given that there are
millions of feral pigs scattered in remote parts of Queensland the
Northern Territory, New South Wales and the ACT with some also in
Western Australia. One approach to this challenge is for Indigenous
communities, particularly Indigenous Land and Sea Ranger groups, to
work with the Australian Quarantine and Inspection Service (AQIS)
by regularly harvesting feral pigs and inspecting them for the
presence of serious exotic diseases like Foot and Mouth
Time Bomb: Mimosa pigra
That the downsides of some of these recent arrivals are now more
obvious is in part because their impacts have often taken a long
time to become apparent. For example, one of northern
Australia’s most significant weeds, the giant sensitive
plant, Mimosa pigra, started off as an introduced ornamental plant
which was unnoticed in the landscape for many decades until it
became a serious pest in the 1980s. It is now apparent that
impacts from introduced organisms are not only damaging the
environment but damaging the economy. It is estimated that weeds
cost the Australian economy $4 Billion a year and feral animals
$720 million a year.
These costs are from pests and diseases already in Australia and
while Australia enjoys a relatively high level of biosecurity due
to its high standards of living, strict quarantine regulations and
its geographic isolation, the costs could be much greater in the
future if the influx of organisms is not addressed, particularly if
pathogens like foot and mouth disease or avian influenza were to
become established in Australia.
What are the future risks in Northern Australia?
Northern Australia is particularly vulnerable to invasion from
organisms beyond our borders: it has an extensive, sparsely
populated coastline that is exposed to the sea-lanes to our north
and it has a tropical environment that can support vigorous plant
growth and harbour many animals. The following risks have been
- Spread of infectious disease such as tuberculosis through
- Spread of mosquito-borne diseases such as the dangerous Ross
river virus, dengue fever, Japanese encephalitis and malaria pose a
serious risk to human health and can cause death.
- Introduction of avian influenza or “bird flu”
virus, carried in poultry and wild birds poses a serious risk to
Australia’s agricultural economy and a small yet significant
risk to human health.
- Agricultural and economic cost of introducing pests carried in
plant material such as fruit fly and termites.
- Environmental cost of introducing other exotic animals such as
cats, dogs and marine pests.
The small population density of northern Australia means that if
well-managed, the risks above are relatively small; however, they
are of particular concern given the trends below.
- An increasing number of illegal foreign fishing vessels
entering Australian waters, mainly from Indonesia.
- An increasing number of unauthorised land incursions from
overseas, including refugees.
- The change in distribution of pathogens within Indonesia due to
eastern migration of communities.
- Climate change is likely to cause global warming of 1.4-5.8
degrees Celcius by 2100. This is likely to affect the
distribution of vectors such as mosquitoes and ticks through
changes in the distribution of rainfall, occurrence of extreme
weather events and distribution of arthropod habitat.
Australia is likely to be at greater risk to the increased
distribution and occurrence of some vector-borne and water-borne
diseases including dengue fever, malaria, Ross River virus and
diarrhoea because of a global temperature rise. Remote indigenous
communities are particularly vulnerable to these diseases. The
degree of impact of climate change upon the spread of vectors
remains largely uncertain.
What should be done?
A number of elements are high on the list when it comes to
maintaining biosecurity for northern Australia:
- Strict quarantine regulations
- Border patrol to detect illegal vessels
- Treatment and destruction of illegal vessels potentially
carrying pathogens and pests.
- Quarantine of people and animals aboard a detained illegal
- Mitigation of climate change
- Vigilant monitoring of areas most vulnerable in Australia
through sampling of known potential vectors.
- Mapping of the distribution of disease, pests and vector
Many of these activities are already being undertaken in the
north by AQIS – the Australian Quarantine and Inspection
Service through its North Australian Quarantine Strategy (NAQS).
Under this strategy AQIS is undertaking scientific surveys and
monitoring, border activities, on and off shore capacity building
and public awareness activities. Much of this activity
involves collaboration with local Indigenous communities.
At the national level the Australian Biosecurity group, convened
by the Invasive Animals and Weeds Cooperative Research Centres and
WWF-Australia, consider that Australia’s biossecurity shield
has a number of shortcomings that could be addressed by the
following broad initiatives:
- National institutions (including a lead Australian Government
body) dedicated to invasive species
- A coherent policy framework
- A strong regulatory framework
- A seamless and stream-lined response framework
- A national framework for prevention and early detection
- A national education, training and action program
- A national information system
- A fund for strategic research
- Equitable industry contributions to improve detection and
- Cost-sharing arrangements to fund detection and eradication of
both environmental and agricultural threats
Opportunities for northern Australia
The location of indigenous communities makes them well-placed to
monitor Australia’s northern coastline. 75% of the area
covered by the NAQS area is Aboriginal Land. Indigenous
people living along Australia’s north coast possess a
detailed knowledge of their traditional country, including flora
and fauna, tides and fishing grounds.
The Northern Land Council (NLC) has a partnership with AQIS to
provide surveillance of the coastline. Indigenous Sea and Land
Rangers also sample for pest plants and animals and detect outbreak
of diseases in plants and animals.
Remote Indigenous communities have high unemployment rates due to
lack of employment opportunities. The common form of
employment is through Community Development Employment Projects
(CDEP), a form of work-for-the-dole. Expanding monitoring of
the NAQS area by Indigenous Sea and Land Rangers is an opportunity
for people living in remote indigenous communities to receive
training and employment. Further employment opportunities
associated with managing biosecurity risk, such as pest control,
also exist. Greater funding is needed for these programs so
that wages for indigenous employees can be made equivalent to those
of non-indigenous people employed by Customs and AQIS and to extend
the Ranger Program to other communities.
Australian Biosecurity Group (2005) Invasive Weeds, Pests and
Diseases: Solutions to Secure Australia, CRC for Pest Animal
Control, CRC for Australian Weed Management and WWF Australia,
Choquenot, D., McIlroy, J. & Korn, T. (1996) Managing
Vertebrate Pests: Feral Pigs, Bureau of Resource Sciences,
Australian Government Publishing Service, Canberra.
Marley, J., Armstrong, R., Morrison, J., and Yu, P. (2007)
Indigenous Communities are Ideally Located to Monitor and Reduce
the Biosecurity Risks Associated with Illegal Foreign Fishing and
Climate Change in Northern Australia. NAILSMA discussion paper (see
link above right).