BIOSECURITY AND REGULATION
INVASIVE SPECIES POSITION STATEMENT
Priority Declared Species - Agricultural Impact
Lead Author(s):
I-Lyn Loo, Senior Policy Officer, Invasive Species
Andrew Reeves, Development Officer, Invasive Species
Reviewed by:
Kay Bailey, Manager Priority Weed Response
Malcolm Kennedy, Research Officer, Invasive Species
Tim Thompson, A/Manager Engagement and Adoption
Richard Watkins, Manager Priority Pest Animal Response
Approved by:
Viv Read, Director Invasive Species
Kevin Chennell, Executive Director Biosecurity and Regulation
Rob Delane, Director General
Date approved:
5 June 2015
Date for review:
12 May 2016
Person responsible to keep
and maintain this document:
Senior Policy Officer, Invasive Species
Position statement number:
03
Version number:
v3_2015
EXECUTIVE SUMMARY
In an environment of reducing resources, government resources must be targeted at activities
that provide the greatest benefit or return in investment. This position statement identifies the
priorities for activities of the Invasive Species Program in managing declared pests that are
invasive species. Prioritisation is carried out based on their impact on agriculture. While all
plants and vertebrate animals declared under the Biosecurity and Agriculture Management Act
2007 (BAM Act) are considered during the prioritisation process, the key factor in determining
the priorities is the species’ impact on agriculture to provide guidance on the resource allocation
for the Invasive Species Program. This position statement excludes invasive species declared
or prescribed under other legislation and the resource allocations of the relevant administering
agencies.
The Invasive Species Plan for Western Australia identifies two groups of priority invasive
species – high priority species and high profile species. High priority species are declared
species that have the potential to cause the highest impact on agriculture while high profile
species are species that biosecurity groups identified as their priority for control in the area.
High priority species
Responding to incursions of invasive species not known to be present in Western Australia is
the highest priority for the Invasive Species Program.
The high priority list for declared plant species known to be present in Western Australia was
developed through expert panels and economic analysis. The prioritisation process was carried
out in two steps. Firstly, the species were ranked in accordance with their impact on agriculture
in a nil management scenario. Next, an economic analysis was carried out on the top ten
ranked declared plant species to determine their impact on agriculture based on a nil
management scenario.
Table A provides the list of high priority declared plant species for Western Australia based on
the two-step prioritisation process. An economic analysis has yet to be carried out on species
ranked 11 to 15.
Table A: High priority declared plant species for Western Australia
Responding to incursions of invasive species not known to be present in Western
Australia is the highest priority for the Invasive Species Program
Priority
number
Declared plant species
1
Gamba grass
Andropogon gayanus
2
Rubber vine
Cryptostegia grandiflora
3
Mesquites
Prosopis glandulosa x velutina, P. glandulosa and P. pallida
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4
Skeleton weed
Chondrilla juncea
5
Hoary Cress
Lepidium draba
6
Mimosa
Mimosa pigra
7
Devil’s rope cactus
Cylindropuntia imbricata
8
Hudson pear
Cylindropuntia rosea
9
Coral cactus
Cylindropuntia fulgida var. mamillata
10
Three-horned bedstraw
Galium tricornutum
11
Prickly pear
Opuntia spp.
12
Prickly acacia
Acacia nilotica
13
Two-leaf cape tulip
Moraea miniata
14
Cane or Snake cactus
Austrocylindropuntia cylindrica
15
Saffron thistle
Carthamus lanatus
Due to the inconsistency in the criteria applied for declared vertebrate animals during the
ranking assessments and economic analysis, the prioritisation process applied to declared plant
species cannot be applied to declared vertebrate animals. The prioritisation process for
declared vertebrate animals was carried out using their location on the generalised invasion
curve (Figure 1) as the first step.
A spatial differentiation was made for wild dogs (Canis lupus familiaris (feral), Canis lupus dingo
x Canis lupus familiaris and Canis lupus dingo), feral goats (Capra hircus (feral), and water
buffalo (Bubalus bubalis)) as their presence are viewed differently in different areas of Western
Australia. These three species were ranked in accordance with their earliest stage of invasion
(e.g. feral goats are categorised as stage 1 during the ranking process).
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The second step ranks the species within each stage of invasion using its rank from the expert
panel assessment. The ranking of declared vertebrate animals was carried out based on the
impact of each species in the current management scenario.
The priority list is intended to guide operations of the Invasive Species Program. Therefore
species with nil documented agricultural impact (such as geckos (Hemidactylus frenatus) and
flowerpot snakes (Ramphotyphlops braminus)) and species with management led by another
government agency (such as cane toads (Bufo marinus)) are removed from the list.
Table B provides the list of high priority declared vertebrate animal species for Western
Australia based on the prioritisation process for declared vertebrate animal species.
Activities of the Invasive Species Program will be focused on the management and control of
these species. Compliance and enforcement activities through tools provided for under the BAM
Act will be used to streamline the Program’s response to these species.
Table B: High priority declared vertebrate animal species for Western Australia
Responding to incursions of invasive species not known to be present in Western
Australia is the highest priority for the Invasive Species Program
Priority
number
Declared vertebrate animal species
Area
1
European starling
Sturnus vulgaris
2
Feral goat
Capra hircus
3
Sulphur-crested Cockatoo
Cacatua galerita
Whole of state
4
Northern Palm Squirrel
Funambulus pennantii
Whole of state
5
Wild dogs
Canis lupus dingo, Canis lupus
familiaris and Canis lupus dingo x
Canis lupus familiaris
South-west Western Australia
6
Rainbow lorikeet
Trichoglossus haematodus
Outside the containment line
7
Fallow deer
Dama dama
Whole of state
8
Wapiti, Red deer, elk
Cervus elaphus
Whole of state
Whole of state
South-west Western Australia
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9
Feral pig
Sus scrofa
Whole of state
10
Feral camel
Camelus dromedarius (feral)
Whole of state
11
Red fox
Vulpes vulpes
Whole of state
12
Feral donkey
Equus asinus (feral)
Whole of state
13
Western corella (northern and central
wheatbelt subspecies)
Cacatua pastinator butleri
Whole of state
14
Feral horse
Equus caballus (feral)
Whole of state
15
Wild rabbit
Oryctolagus cuniculus
Whole of state
High profile species
The Invasive Species Program also recognises that there may be declared invasive species that
are not considered high priority species in terms of their impact on agriculture but are of
importance and significance to “eligible”1 biosecurity and community groups. The BAM Act
provides the recognised biosecurity group framework to underpin the response to these
species, termed high profile species. The Invasive Species Program will respond to the
management of these species through the community coordinated approach. The Program will
support the community coordinated approach with compliance and enforcement activities within
its resource capability.
1
An eligible biosecurity or community group is a group that has:
 An operational plan in place
 A communications and engagement strategy developed and implemented
 A best practice management guidance for management of target species, developed in partnership
with the Invasive Species Program (including timeframe for activities and the preferred control
techniques)
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Table C: High profile species in Western Australia
Species name
Declared plant or
declared vertebrate
animal
Coral cactus2
Cylindropuntia fulgida var. mamillata
Plant
Pilbara and Southern
Rangelands
Prickly pear3
Opuntia spp.
Plant
Pilbara and Southern
Rangelands
Prickly acacia4
Acacia nilotica
Plant
Kimberley
Rubber vine5
Cryptostegia grandiflora
Plant
Kimberley
Mesquites6
Prosopis glandulosa, Prosopis
pallida, Prosopis glandulosa x
velutina
Plant
Pastoral region
Parkinsonia
Parkinsonia aculeata
Plant
Pastoral region
Narrow leaf cotton bush
Gomphocarpus fruticosus
Plant
South-west
Paterson’s curse
Echium plantagineum
Plant
South-west
Apple of Sodom
Solanum linnaeanum
Plant
South-west
Blackberry
Rubus spp.
Plant
South-west
Cape tulips
Moraea miniata, Moraea flaccida
Plant
South-west
2
Coral cactus is also a high priority species.
Prickly pear is also a high priority species.
4 Prickly acacia is also a high priority species.
5 Rubber vine is also a high priority species.
6 Mesquites are also high priority species.
3
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Region
Wild dogs (including dingoes, feral
dogs and dingo-dog hybrids)
Canis lupus familiaris (feral), Canis
lupus dingo, Canis lupus familiaris x
Canis lupus dingo
Vertebrate animal
Pastoral region
Rainbow lorikeet
Trichoglossus haematodus
Vertebrate animal
Perth metropolitan area
Feral camel
Camelus dromedarius (feral)
Vertebrate animal
Feral pig
Sus scrofa
Vertebrate animal
Feral donkey
Equus asinus (feral)
Vertebrate animal
Feral horse
Equus caballus (feral)
Vertebrate animal
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Pastoral regions
South-west land division
Pastoral regions
Pastoral regions
1. BACKGROUND
Government agencies are continually challenged to demonstrate value for money and to show
that they are meeting the needs of their clients and stakeholders.
Invasive species management requires an investment by the community in the exclusion,
eradication or management of a pest species that has the potential to cause significant
economic damage to agricultural enterprises by impacting upon production, productivity and in
some cases disrupting export markets.
In an environment of reducing resources, it becomes more essential for those resources to be
targeted towards management of declared invasive species that yields the most benefits to the
agriculture sector in Western Australia.
2. PURPOSE AND SCOPE
Purpose of this position statement: This position statement provides strategic direction and
clarity to the Invasive Species Program through the identification of high priority and high profile
declared invasive species in Western Australia based on their impact on agriculture. It also
outlines the Program’s general approach to management of these high priority and high profile
species.
Scope of this position statement: The declared pests covered under this position statement
include plants and vertebrate animals declared under the Biosecurity and Agriculture
Management Act 2007 (BAM Act). The statement excludes invasive species declared or
prescribed under other legislation and the resource allocations by the relevant administering
agencies. It also does not cover diseases or invertebrate organisms.
3. RELEVANT LEGISLATION
The BAM Act and its regulations took full effect on 1 May 2013 replacing the Agriculture and
Related Resources Protection Act 1976. Under the BAM Act, organisms can be declared as:



Permitted under section 11;
Prohibited under section 12; or
Declared pests under section 22(2).
Organisms that are not on any of these lists are known as unlisted organisms under section 14
of the BAM Act.
The declaration of organisms under one of the three categories is based on its likely adverse
impacts on another organism, human beings, the environment or part of the environment or
agricultural activities, fishing or pearling activities or related commercial activities in Western
Australia. Declaration can be for the whole or part of the state.
Prohibited organisms and section 22(2) declared pests can be assigned to control categories
based on the extent of their presence in Western Australia. Three control categories exist under
the BAM Act:
 Category 1 – Prevention (C1)
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

Category 2 – Eradication (C2)
Category 3 – Management (C3)
Prohibited organisms and section 22(2) declared pests can also be assigned to keeping
categories, which determines the keeping permit requirements for each of these species.
The draft BAM Act Policy BAM1.0 Declaring the status of organisms provides further information
on the process and criteria for declaring organisms under the BAM Act.
4. LINK TO THE INVASIVE SPECIES PLAN FOR WESTERN
AUSTRALIA
The Invasive Species Plan for Western Australia 2015-2019 (State IS Plan) outlines Western
Australia’s approach to managing existing and potential invasive species that can harm the
state’s economy, environment and people. The State IS Plan identifies two groups of priority
invasive species – high priority species and high profile species.
High priority invasive species are defined in the State IS Plan as high risk species that can
establish widely and if so cause the most undesirable impact. These species are also likely to
be feasibly prevented, eradicated and contained or controlled. For the purposes of this position
statement, impact on agriculture will be the primary consideration when determining high priority
invasive species.
High profile invasive species are defined in the State IS Plan as declared species assessed by
the community – normally already widely established – as being major problems. This definition
will be applied in this position statement.
5. DEVELOPING THE LIST OF PRIORITY SPECIES
5.1 Invasive species not known to be present in Western
Australia
The Invasive Species Program’s approach to managing declared invasive species aligns with
the generalised invasion curve (Figure 1). This approach is consistent with that taken in the
State IS Plan.
In general, the most cost effective actions are in preventing a new invasive species entering or
eradicating it before it becomes widely established. At this stage, government intervention is
most needed and often delivers the greatest return on investment. Responding to the presence
of invasive species that are not known to be present in Western Australia7 is considered to be
the highest priority for the Invasive Species Program. These species are not ranked or
prioritised in this position statement as all incursions are treated as highest priorities for the
Program.
7
Declared invasive species that are not known to be present in Western Australia are typically
categorised in the C1 (exclusion) control category. However, there may be unknown invasive species that
are not declared under the BAM Act that may be detected and cause impact to agriculture in Western
Australia. These species are unlisted species under section 14 of the BAM Act.
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Figure 1 Generalised Invasion Curve
Source: Victoria Department of Environment and Primary Industries
5.2 High priority declared species known to be present in
Western Australia
Declared invasive species that are known to be present in Western Australia are typically
categorised in the C2 (eradication) and C3 (management) control categories. Management of
these species form the bulk of activities within the Invasive Species Program.
5.2.1
Declared plants
The prioritisation process for declared plants known to be present in Western Australia was
carried out in two steps. The first step was a declared pest ranking assessment and the second
step was an economic analysis of the top ten declared plant species as ranked in the first step.
Declared pest ranking assessment
Declared species that are known to be present in Western Australia were ranked by an expert
panel based on the species’ impacts on agriculture. The ranking of declared plants was carried
out based on the impact of each species in a nil management scenario. Appendix 1 provides
the details of the method for ranking declared plants.
The ranking of a species is based on the average score from the panel. The score takes into
account the invasiveness of the species and its capacity to change its surrounding.
The ranked list of plant species based on their impacts on agriculture is at Appendix 2.
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Economic analysis
For the top ten ranked declared plant species from the declared pest ranking assessment, an
economic impact assessment was conducted. This assessment built on the ranking of the
expert panels and provided a quantitative estimated cost to the impact of each species to
agriculture.
A model was constructed to calculate the potential impact of the top ten ranked declared plants
on agricultural production over time (Cook, 2014a). The model allowed species to be prioritised
in two different ways using two scenarios:
1.
Management scenario - in which an eradication or a ‘slow-the-spread’ policy is either in
place or intended;
2.
Nil management scenario - where minimal effort is made to control a pest, providing an
indication of the natural capacity of the pest to inflict damage on Western Australia’s
(WA) agricultural economy.
The resultant list from the first scenario provided the benefits in economic terms of the current or
proposed management strategies of the IS Program. The quantitative benefits of from this list
were used to calculate the cost-benefit ration of management actions and to determine the
maximum amount of expenditure for any current or proposed management actions.
The list from the second scenario provided the quantitative cost to Western Australian
agriculture with no intervention or management of the species. This list was used as the basis
for determining the priorities for Western Australia and is shown in Table 1. The cost presented
against each species represents the potential damage to Western Australia due to the
unmanaged spread of each species.
5.2.2
Declared vertebrate animals
Analysis and categorisation of the stage of invasion
The generalised invasion curve (Figure 1) shows that the indicative economic returns are higher
when intervention is applied at the earlier stages of invasion. This provides a rationale for
government intervention in prevention of new invasive species and eradication of small
populations.
Due to the inconsistency in the criteria applied for declared vertebrate animals during the
ranking assessments and economic analysis, the prioritisation process applied to declared plant
species cannot be applied to declared vertebrate animals.
The prioritisation process for declared vertebrate animals was carried out using their location on
the generalised invasion curve (Figure 1) as the first step. Each of the declared pest animals
were categorised into four categories based on its stage of invasion (from 1 to 4), from the
earliest stage (stage 1) to widespread and well established (stage 4).
A spatial differentiation was also made for wild dogs (Canis lupus familiaris (feral), Canis lupus
dingo x Canis lupus familiaris and Canis lupus dingo) and feral goats (Capra hircus (feral)) as
their presence are viewed differently in the south-west as opposed to across the whole of the
state. A similar approach was taken for water buffalo (Bubalus bubalis) as the species is
categorised at the earliest stage of invasion north of the 20th parallel and widespread and
established south of the 20th parallel. These three species were ranked in accordance with their
earliest stage of invasion (e.g. feral goats are categorised as stage 1 during the ranking
process).
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Declared pest ranking assessment
The second step ranks the species within each stage of invasion using its rank from the expert
panel assessment. The ranking of declared vertebrate animals was carried out based on the
impact of each species in the current management scenario. Appendix 1 provides the details of
the method for ranking declared vertebrate animals.
The ranking of a species is based on the average score from the panel. The score takes into
account the invasiveness of the species and its capacity to change its surrounding. The ranked
list of vertebrate animal species based on their impacts on agriculture is at Appendix 2.
The priority list is intended to guide operations of the Invasive Species Program. Therefore
species with nil documented agricultural impact (such as geckos (Hemidactylus frenatus) and
flowerpot snakes (Ramphotyphlops braminus)) and species with management led by another
government agency (such as cane toads (Bufo marinus)) are removed from the list.
Economic analysis
An economic analysis was carried out for the top ten declared vertebrate animal species ranked
in accordance with their impact on agriculture in the current management scenario. The analysis
was carried out in the same method for the top ten declared plant species. The method is
described in the Impact Assessments for Vertebrate Pests in Western Australia Strategic Report
(Cook, 2014b).
The results of the economic analysis was not used in the prioritisation process but included
where relevant in the priority list to provide an indication of the economic impact of the species
in a nil management scenario.
The intention in the long term is to progress towards a prioritisation process where the economic
analysis of the impact of the species is the primary consideration.
5.3 High profile species
The Invasive Species Program recognises that while some declared invasive species might not
be a high impact species based on the methodologies in sections 5.2.1 and 5.2.2, these species
might be of importance to the community. These are termed high profile species and typically
there is organised community effort in managing the impacts and spread of these species.
For a species to be classified as a high profile species, it must be:


8
A declared pest, typically but not always established and widespread
Considered a priority species for an eligible8 biosecurity or community group that is
recognised or intending to seek recognition from the Minister under section 169 of the
BAM Act
An eligible biosecurity or community group is a group that has:
 An operational plan in place
 A communications and engagement strategy developed and implemented
 A best practice management guidance for management of target species, developed in partnership
with the Invasive Species Program (including timeframe for activities and the preferred control
techniques)
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6. PRIORITY SPECIES FOR THE IS PROGRAM
This section lists the priority species for the Invasive Species Program that are known to be
present in Western Australia.
6.1 High priority species
High priority species are determined based on the prioritisation process outlined in section 5.2.
Table 1: High priority declared plants for Western Australia
Responding to incursions of invasive species not known to be present in Western
Australia is the highest priority for the Invasive Species Program
Priority
number
Species name
Impact on agriculture in Western
Australia based on a nil
management scenario
($ millions per year)
1
Gamba grass
Andropogon gayanus
110.0
2
Rubber vine
Cryptostegia grandiflora
38.4
3
Mesquites
Prosopis glandulosa x velutina, P.
glandulosa and P. pallida
12.0
4
Skeleton weed
Chondrilla juncea
6.5
5
Hoary Cress
Lepidium draba
6.2
6
Mimosa
Mimosa pigra
6.0
7
Devil’s rope cactus
Cylindropuntia imbricata
3.5
8
Hudson pear
Cylindropuntia rosea
3.5
9
Coral cactus
Cylindropuntia fulgida var. mamillata
3.1
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10
Three-horned bedstraw
Galium tricornutum
11
Prickly pear
Opuntia spp.
Cost to be determined
12
Prickly acacia
Acacia nilotica
Cost to be determined
13
Two-leaf cape tulip
Moraea miniata
Cost to be determined
14
Cane or Snake cactus
Austrocylindropuntia cylindrica
Cost to be determined
15
Saffron thistle
Carthamus lanatus
Cost to be determined
1.5
An economic analysis has yet to be carried out on declared plant species ranked 11 to 15.
These species have been added to the table based on their ranking in the expert ranking
approach, which is based on a nil management scenario. Economic analysis is planned for
these and other lower ranked species and the outcomes of the analysis may alter the priority
list.
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Table 2: High priority declared vertebrate animals for Western Australia
Responding to incursions of invasive species not known to be present in Western
Australia is the highest priority for the Invasive Species Program
Priority
number
Species name
Impact on agriculture in Western
Australia based on a nil
management scenario9
($ millions per year)
1
European starling
Sturnus vulgaris
2
Feral goat11
Capra hircus
3
Sulphur-crested Cockatoo
Cacatua galerita
Cost to be determined
4
Northern Palm Squirrel
Funambulus pennantii
Cost to be determined
5
Wild dogs12
Canis lupus dingo, Canis lupus
familiaris and Canis lupus dingo x
Canis lupus familiaris
8.1
6
Rainbow lorikeet13
Trichoglossus haematodus
3.2
7
Fallow deer
Dama dama
Cost to be determined
8
Wapiti, Red deer, elk
Cervus elaphus
Cost to be determined
9
Feral pig
Sus scrofa
11.710
7.7
4.6
9
The cost to agriculture under a nil management scenario appears unusual as the priority list was
determined based on the stage of invasion of each species rather than based on the economic analysis.
10 Campbell et al (in press) quantified the impact of the European starlings as $42.8m per year. This
figure is not utilised in the prioritisation process as it does not provide a consistent comparison across all
the declared vertebrate animals.
11 In south-west Western Australia.
12 In south-west Western Australia.
13 Outside the containment line.
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10
Feral camel
Camelus dromedarius (feral)
7.3
11
Red fox
Vulpes vulpes
1.9
12
Feral donkey
Equus asinus (feral)
13
Western corella (northern and central
wheatbelt subspecies)
Cacatua pastinator butleri
Cost to be determined
0.9
14
Feral horse
Equus caballus (feral)
Cost to be determined
15
Wild rabbit
Oryctolagus cuniculus
15.8
An economic analysis has yet to be carried out on some of the declared vertebrate animal
species on the priority list. Economic analysis based on a nil management scenario is planned
for these and other species and the outcomes of the analysis may alter the priority list.
6.2 High profile species
For high profile species, an overall list is provided based on the criteria outlined in section 5.3.
These species will be managed through the community coordinated approach outlined in
section 7.3.
No priority number is assigned to the species as their priorities vary from region to region. This
list of high profile declared plants and vertebrate animals is constantly evolving depending on
the priorities of recognised biosecurity groups or biosecurity groups intending to be recognised
by the Minister under section 169 of the BAM Act.
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Table 3: High profile declared invasive species
Species name
Declared plant or
declared vertebrate
animal
Coral cactus14
Cylindropuntia fulgida var. mamillata
Plant
Pilbara and Southern
Rangelands
Prickly pear15
Opuntia spp.
Plant
Pilbara and Southern
Rangelands
Prickly acacia16
Acacia nilotica
Plant
Kimberley
Rubber vine17
Cryptostegia grandiflora
Plant
Kimberley
Mesquites18
Prosopis glandulosa, Prosopis
pallida, Prosopis glandulosa x
velutina
Plant
Parkinsonia
Parkinsonia aculeata
Plant
Pastoral region
Narrow leaf cotton bush
Gomphocarpus fruticosus
Plant
South-west
Paterson’s curse
Echium plantagineum
Plant
South-west
Apple of Sodom
Solanum linnaeanum
Plant
South-west
Blackberry
Rubus spp.
Plant
South-west
Cape tulips
Moraea miniata, Moraea flaccida
Plant
South-west
14
Coral cactus is also a high priority species.
Prickly pear is also a high priority species.
16 Prickly acacia is also a high priority species.
17 Rubber vine is also a high priority species.
18 Mesquites are also high priority species.
15
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Region
Pastoral region
Wild dogs (including dingoes, feral
dogs and dingo-dog hybrids)
Canis lupus familiaris (feral), Canis
lupus dingo, Canis lupus familiaris x
Canis lupus dingo
Vertebrate animal
Pastoral region
Rainbow lorikeet
Trichoglossus haematodus
Vertebrate animal
Perth metropolitan area
Feral camel
Camelus dromedarius (feral)
Vertebrate animal
Feral pig
Sus scrofa
Vertebrate animal
Feral donkey
Equus asinus (feral)
Vertebrate animal
Feral horse
Equus caballus (feral)
Vertebrate animal
Pastoral regions
South-west land division
Pastoral regions
Pastoral regions
7. IS PROGRAM’S APPROACH TO PRIORITY INVASIVE SPECIES
MANAGEMENT
7.1 Responding to invasive species not known to be present in
Western Australia
Responding to incursions of an invasive species not known to be present in Western Australia
(whether declared or unlisted) is the highest priority for the Invasive Species Program. The
Incursion Response team will lead the response to confirmed reports of incursions with the aim
of preventing the establishment of these species in Western Australia.
These species are typically prohibited organisms declared under section 12 of the BAM Act or
declared pests under section 22(2) and categorised in the C1 (exclusion) control category. They
may also be unlisted species.
7.2 Responding to high priority invasive species
After incursions response outlined in section 7.1, responding to high priority invasive species is
the next priority role for the Invasive Species Program. The priority list outlined in section 6.1
guides the response of the Invasive Species program in the control and management of
declared plants and vertebrate animals.
Where appropriate, response to high priority invasive species will be streamlined using
compliance and enforcement tools provided for under the BAM Act.
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Where there is a high priority species that is also a high profile species in a region, the Invasive
Species Program will also work in partnership with the biosecurity or community group to
manage the infestations of the species.
7.3 Responding to high profile species
The Invasive Species Program’s response to high profile species is through the community
coordinated approach. The Program will adopt shared responsibility with industry and
community for containment and asset-based protection. This will be based on negotiated
partnership arrangements, including options for adopting a community-coordinated approach for
landscape scale control of high profile declared species that involves the formation and
recognition of biosecurity groups.
This approach is underpinned by the recognised biosecurity group (RBG) framework under the
BAM Act. A biosecurity group recognised by the Minister under section 169 of the BAM Act may
receive funds from the Declared Pest Account for the purposes of controlling pests in their area
of responsibility. Funds from the Declared Pest Account consist of rates raised by the Minister
under section 130 of the BAM Act and matching state government funding.
The Invasive Species Program also supports the community-coordinated approach through
compliance and enforcement activities within its resource capability.
8. REVIEW OF THE PRIORITY LISTS
The lists of priority declared plants and declared vertebrate animals will be reviewed in 12
months to take into account new information about their impacts and presence in Western
Australia. New information includes, but is not limited to, economic impacts assessments on
other declared species and review of the existing economic impacts assessments.
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ABBREVIATIONS
BAM Act
Biosecurity and Agriculture Management Act 2007
RBG
Recognised biosecurity group
RELEVANT INFORMATION
Campbell, S. Roberts, E. J., Craemer, R., Pacioni, C, Rollins, L. and Woolnough, A.P. (in
press) Assessing the economic benefits of starling detection and control to Western Australia.
Australasian Journal of Environmental Management
Cook, D. (a) 2014. Agricultural Resource Risk Management. Strategic Report. Impact
Assessments for Declared Plants in Western Australia. June 2014. DAFWA. South West
Agricultural Region. Bunbury
Cook, D. (b) 2014. Agricultural Resource Risk Management. Strategic Report. Impact
Assessments for Vertebrate Pests in Western Australia. November 2014. DAFWA. South West
Agricultural Region. Bunbury
Petersen, E.H, Dodd, J. and Read, V. T. 2014. A decision tool to assist in ranking the declared
plants of Western Australia. In: Proc. 19th Australasian Weed Conference, pages 25-28.
Petersen, E., Kirkpatrick, W., and Rod Randall, R. 2014. Declared Animal – Impact Assessment
and Benefit Cost Analysis. Spreadsheet. Department of Agriculture and Food WA.
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Appendix 1
Declared Plants Impact Assessment
The Impact Assessment employs the Expert Panel Approach (a variant of the Delphi Method), where
highly technical and complex knowledge is synthesised from experts and combined in order to achieve
an optimal decision (see Dufour et al. (2011), Pulkkinen and Simola (2000), and Slocum (2005)). In the
case of this Impact Assessment, a panel of experts who are familiar with the impacts of declared plants
in Western Australia, score each declared plant according to their knowledge of the benefits of
controlling each plant. Agricultural and environmental benefits are scored separately, and both private
(landholder) and public (government and the wider community) benefits are included. The score ranges
from 1 to 5, as shown in the key provided in Table 1. The costs of control are not considered in the
Impact Assessment, as they are more complex in nature and expert knowledge of these costs is more
limited than expert knowledge of the benefits of control.
Table 1: Scoring key for the Impact Assessment
SCORING KEY
Agricultural BENEFITS
1 - Uncontrolled plant has very little impact on
profit
2
3 - Moderate
4
5 - Uncontrolled plant has significant impact on
profit
Environmental BENEFITS
1 - Uncontrolled plant has very little impact on
environment
2
3 - Moderate
4
5 - Uncontrolled plant has significant impact on
environment
The term impact in this assessment has two dimension: (1) a species capacity to change its
surroundings, and (2) a species invasiveness (ability to spread). The impact scores in Table 1 include
these two dimensions as shown in Table 2.
Table 2: Incorporating 'capacity to change' and 'invasiveness' into the impact scores
Capacity to change
Impact score
Low
Moderate
Low
1
2
Invasiveness
Moderate
2
3
High
3
4
High
3
4
5
Expert panel members provide impact scores for each declared plant individually at first. Where there
is little variation in scores by all panel members, the average score is inputting into the Impact
Assessment sheet. Variation is measured as the difference between the maximum and minimum
impact scores. Where this difference is 0, 1 or 2 (i.e. scores are within the range of 1-3, 2-4 or 3-5),
variation is considered to be minor. Where this difference is 3 or 4, the variation is considered to be
significant. For these declared plants, if outliers are observed, they are removed. Outliers are defined
as single minimum or maximum scores which are two scores away from others (i.e. red scores in the
follow: 1,2,3,5 or 1,2,4 or 1,3,4,5 or 1,3,4 etc). After outliers have been removed, if variation is still
significant, expert panel members meet to discuss the impacts of the declared plant and form a
consensus on the impact score for those declared plants.
This process can be repeated as often as required to keep the impact scores relevant depending on
when new plants need to be assessed, and how fast knowledge about the impacts of declared plants
on agriculture and the environment change.
To date, this process has occurred once, between August and December 2013. Panel members in
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December 2013 included:
five non-DAFWA members:
1. Greg Keighery - DPaW
2. Andrew Mitchell - Private weeds
consultant
3. Kellie Passeretto - DPaW
4. John Peirce - retired weeds expert
5. John Scott - CSIRO
6. Jon Dodd
7. Sandy Lloyd
8. John Moore
9. Rod Randall
10. Andrew
Reeves
and five DAFWA members:
The finalised impact scores are provided in the Impact Assessment sheet. Of the 74 types of declared
plants considered, 52 agricultural impact scores and 54 environmental impact scores were determined
by averaging the scores from each expert panel member. These scores had low variability. The
remaining declared plant impact scores were determined at a workshop. The Impact Assessment sheet
indicates which scores were average or workshop determined scores. It also indicates the number of
expert respondents who contributed to the average scores, given that experts only scored those
declared plants with which they were familiar.
The declared plants can be ranked and sorted according to their agricultural and environmental impact
scores in the Sort Impact Assessment sheet. It is intended that this ranking process gives priority to
those declared plants on which a full Benefit Cost Analysis (BCA) is conducted in the Benefit Cost
Analysis sheet.
Declared Animals Impact Assessment
The Impact Assessment employs the Expert Panel Approach (a variant of the Delphi Method), where highly
technical and complex knowledge is synthesised from experts and combined in order to achieve an optimal
decision (see Dufour et al. (2011), Pulkkinen and Simola (2000), and Slocum (2005)). In the case of this
Impact Assessment, a panel of experts who are familiar with the impacts of declared animals in Western
Australia, score each declared animal according to their knowledge of the benefits of controlling each
animal. Agricultural and environmental benefits are scored separately, and both private (landholder) and
public (government and the wider community) benefits are included. The score ranges from 1 to 5, as
shown in the key provided in Table 1. The costs of control are not considered in the Impact Assessment, as
they are more complex in nature and expert knowledge of these costs is more limited than expert
knowledge of the benefits of control.
Table 1: Scoring key for the Impact Assessment
SCORING KEY
Agricultural BENEFITS
1 - Animal has very little impact on profit
2
3 – Moderate
4
5 - Animal has significant impact on profit
Environmental BENEFITS
1 - Animal has very little impact on environment
2
3 – Moderate
4
5 - Animal has significant impact on environment
The term impact in this assessment has two dimension: (1) a species capacity to change its surroundings,
and (2) a species invasiveness (ability to spread). The impact scores in Table 1 include these two
dimensions as shown in Table 2.
Table 2: Incorporating 'capacity to change' and 'invasiveness' into the impact scores
Impact score
Capacity to change
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Invasiveness
Low
Moderate
High
Low
1
2
3
Moderate
2
3
4
High
3
4
5
Expert panel members provide impact scores for each declared animal individually at first. Where there is
little variation in scores by all panel members, the average score is inputting into the Impact Assessment
sheet. Variation is measured as the difference between the maximum and minimum impact scores. Where
this difference is 0, 1 or 2 (i.e. scores are within the range of 1-3, 2-4 or 3-5), variation is considered to be
minor. Where this difference is 3 or 4, the variation is considered to be significant.
For these declared animals, if outliers are observed, they are removed. Outliers are defined as single
minimum or maximum scores which are two scores away from others (i.e. red scores in the follow: 1,2,3,5
or 1,2,4 or 1,3,4,5 or 1,3,4 etc). After outliers have been removed, if variation is still significant, expert panel
members meet to discuss the impacts of the declared animal and form a consensus on the impact score
for those declared animals.
The expert panel was made up of a range of research and operational based staff with skills across a wide
range of fields and species. Despite this difference of basic backgrounds the scores allocated were
generally equitable between the two groups with no obvious bias detected.
This process can be repeated as often as required to keep the impact scores relevant depending on when
new animals need to be assessed, and how fast knowledge about the impacts of declared animals on
agriculture and the environment change.
To date, this process has occurred once, between August and December 2013. Panel members in
December 2013 included:
DAFWA members: 1. James Sheehan - W
2. Simon Merewether - (W Andrew
Reeves)
3. Gary Martin - W
4. Brett Scourse - W
5. Win Kirkpatrick - W
6. Susan Campbell - W
7. Ian Wilkinson - W
8. Paul Manera
9. Malcolm Kennedy - W
10. Andrew Longbottom
non-DAFWA members: 11. Kevin Morrison
12. Dennis Rafferty - W
13. Manda Page - W
14. Peter Mawson - W
Those members who attended the May 2014 workshop for the final ranking round have a 'W' after their
name.
Species were assessed on their impact under a ‘current control’ scenario, except starlings which were
retrospectively considered under a ‘nil management scenario’ following the workshop. The finalised impact
scores are provided in the Impact Assessment sheet, which indicates which scores were average or
workshop determined scores. It also indicates the number of expert respondents who contributed to the
average scores, given that experts only scored those declared animals with which they were familiar.
The declared animals can be ranked and sorted according to their agricultural and environmental impact
scores in the Sort Impact Assessment sheet. It is intended that this ranking process gives priority to those
declared animals on which a full Benefit Cost Analysis (BCA) is conducted in the Benefit Cost Analysis
sheet.
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Appendix 2
Declared plants ranked in accordance with their agricultural impact
DECLARED PLANT (Including Weeds of National Significance)
Ranking
Common Name(s)
Scientific name
gamba grass
three-horned bedstraw
mesquite
skeleton weed
hoary cress
mesquite
mesquite
mimosa
rubber vine
Coral cactus or Boxing glove cactus
(Opuntioid cactus)
Devil's rope cactus (Opuntioid cactus)
Hudson pear (Opuntioid cactus)
prickly pear
prickly acacia
two-leaf cape tulip
Cane or Snake cactus (Opuntioid cactus)
saffron thistle
doublegee
parkinsonia
Andropogon gayanus
Galium tricornutum
Prosopis glandulosa x velutina
Chondrilla juncea
Lepidium draba
Prosopis glandulosa
Prosopis pallida
Mimosa pigra
Cryptostegia grandiflora
1
2
3
4
4
4
4
8
9
Cylindropuntia fulgida var. mamillata
9
Cylindropuntia imbricata
Cylindropuntia rosea
Opuntia spp
Acacia nilotica
Moraea miniata
Austrocylindropuntia cylindrica
Carthamus lanatus
Emex australis
Parkinsonia aculeata
9
9
9
14
15
16
16
16
16
ragwort
Senecio jacobaea
16
Bathust burr
cotton bush, narrow leaf cotton bush
Paterson's curse
camelthorn
one-leaf cape tulip
Noogoora burr
artichoke thistle, cardoon
apple of Sodom
variegated thistle
African thistle
calotropis
heliotrope
bellyache bush
alligator weed
rubber vine
golden dodder
St John's wort
stemless thistle
blackberry
salvinia
Silverleaf nightshade
gorse
arum lily
thornapple
Xanthium spinosum
Gomphocarpus fruticosus
Echium plantagineum
Alhagi maurorum
Moraea flaccida
Xanthium strumarium
Cynara cardunculus
Solanum linnaeanum
Silybum marianum
Berkheya rigida
Calotropis procera
Heliotropium europaeum
Jatropha gossypiifolia
Alternanthera philoxeroides
Cryptostegia madagascariensis
Cuscuta campestris
Hypericum perforatum
Onopordum acaulon
Rubus spp
Salvinia molesta
Solanum elaeagnifolium
Ulex europaeus
Zantedeschia aethiopica
Datura spp
21
22
23
24
24
24
27
27
29
30
30
30
30
34
34
34
34
34
34
34
34
34
43
44
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Ziziphus mauritiana
Marrubium vulgare
Salvia reflexa
Tamarix aphylla
Argemone ochroleuca
Convolvulus arvensis
Sagittaria platyphylla
Senna alata
Senna obtusifolia
Asparagus spp
Hydrocotyle ranunculoides
Genista monspessulana
Anredera cordifolia
Pistia stratiotes
Eichhornia crassipes
Sida acuta
Sida cordifolia
Salix spp
Cytisus scoparius
Carthamus leucocaulos
Chrysanthemoides monilifera subsp. monilifera
Chrysanthemoides monilifera subsp. rotundata
Egeria densa
Emex spinosa
Genista linifolia
Lantana camara
Lycium ferocissimum
Myriophyllum aquaticum
Praxelis clematidea
chinee apple
horehound
mintweed
athel pine
Mexican poppy
field bindweed
sagittaria
candle bush
sicklepod, javabean
Weedy asparagus
hydrocotyl
Montpellier broom
Madeira vine
water lettuce
water hyacinth
sida
sida
willow
Scotch broom
glaucous star thistle
boneseed
bitou bush
leafy elodea
lesser jack
Flax-leaf broom
lantana
African boxthorn
parrot's feather
praxelis
45
46
46
46
49
49
49
49
49
54
54
56
57
57
59
59
59
62
63
64
64
64
64
64
64
64
64
64
64
Declared animals ranked in accordance with their agricultural impact
DECLARED ANIMAL
Ranking
Common Name(s)
Scientific name
European Starling, Common Starling
wild rabbit only with wild-type brown
colouring
Dingo
Sturnus vulgaris
1
Oryctolagus cuniculus (feral)
2
Canis lupus dingo
3
Dingo-dog hybrids
Canis lupus dingo x Canis lupus familiaris
3
Feral Dog
Canis lupus familiaris (feral)
3
Rainbow Lorikeet
Trichoglossus haematodus
6
Feral goat
Wild boar, Feral pig
Capra hircus (feral)
Sus scrofa (feral)
7
8
feral camel
Camelus dromedarius (feral)
9
Red Fox
Vulpes vulpes
10
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water buffalo
western corella (northern and central
wheatbelt subspecies)
western corella (Lake Muir subspecies),
Muir's Corella
Fallow deer
Feral donkey
Wapiti, Red deer, Elk
long-billed black cockatoo, Baudin’s
Cockatoo
sulphur-crested Cockatoo
Bubalus bubalis
11
Cacatua pastinator butleri
11
Cacatua pastinator pastinator
11
Dama dama
Equus asinus (feral)
Cervus elaphus
11
11
16
Calyptorhynchus baudinii
17
Cacatua galerita
18
Red Kangaroo, Marlu
Macropus rufus
19
twenty-eight parrot
Barnardius zonarius
20
Feral horse
Equus caballus (feral)
20
Agile Wallaby
WA King Parrot, Red-capped Parrot
Macropus agilis
Purpureicephalus spurius
22
23
Emu
Dromaius novaehollandiae
24
Western Grey Kangaroo
Euro, Biggada
little corella (Kimberley subspecies)
little corella (Pilbara-Murchison and
northern wheatbelt subspecies)
Macropus fuliginosus
Macropus robustus erubescens
Cacatua sanguinea sanguinea
24
24
27
Cacatua sanguinea westralensis
27
Maned Goose, Australian Wood Duck
Chenonetta jubata
29
Mountain Duck, Australian Shelduck
Tadorna tadornoides
30
galah
Cacatua roseicapilla
31
Long-haired Rat
Rattus villosissimus
32
Ostrich
Struthio camelus
32
Silvereye
Zosterops lateralis
32
domestic rabbit or commercial breeds
Australian Raven
ring-necked pheasant, Common pheasant
Ferret
cane toad
Northern Palm Squirrel
Common House Gecko, Bridled House
Gecko
Flowerpot Snake, Brahminy blindsnake,
Bootlace Snake
Oryctolagus cuniculus (domestic)
Corvus coronoides
Phasianus colchicus
Mustela putorius furo
Bufo marinus
Funambulus pennantii
35
36
37
38
39
40
Hemidactylus frenatus
41
Ramphotyphlops braminus
41
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