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Module 2:Overview and history of pest fish management

Module 2:

Overview and history of pest fish managementObjectives • Participants will be provided with an overview of

what government bodies are currently doing and have been doing to tackle the pest fish problem

• Participants will gain an understanding of how pest fish fit in with the broader river health and rehabilitation and will be introduced to the concept of demonstration reaches

• Participants will have an understanding of the limitations currently faced by government bodies and why it is important to raise community awareness

Intended participants • All stakeholder groups

Key messages • Government bodies have been devising and

updating strategies aimed at tackling the problem of pest fish for years

• The current aim is to increase community awareness and engagement

• Pest fish management needs to be incorporated into the broader river health and rehabilitation

Learning resources • PowerPoint• Case studies• Learning activities• DEEDI and NSW DPI pest fish communications material• Further reading: Queensland Murray–Darling

Committee, Border Rivers Demonstration Reach: <www.qmdc.org.au>

Strategies Queensland

– Department of Primary Industries (2000). Control of exotic pest fishes—an operational strategy for Queensland freshwaters 2000–2005: <www.fisheries.qld.gov.au>

New South Wales – Department of Industry and Investment (2010). NSW control plan for the noxious fish carp Cyprinus carpio: <www.dpi.nsw.gov.au>

National – Natural Resource Management Ministerial Council (2006). A strategic approach to the management of ornamental fish in Australia: <www.dpi.nsw.gov.au>

– Carp Control Coordination Group (2000). National management strategy for carp control 2000–2005: <publications.mdbc.gov.au>

– Murray–Darling Basin Ministerial Council (2004). Native fish strategy for the Murray–Darling Basin 2003–2013: <www2.mdbc.gov.au/NFS>

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A history lesson in pest fish management

Queensland

Before 2000, management actions aimed at controlling pest fish were generally limited to the development of legislation regarding the possession and movement of fish classified as noxious. A permit system for noxious fish (including tilapia) was developed allowing the possession of fish for educational display purposes only. Educational materials, such as posters, brochures, flyers and media campaigns, warning the community of the dangers of pest fish were developed for some species.

In 2000, the Queensland Government, recognising the need for a more active approach to pest fish management, developed a strategy for the control of exotic pest fishes. The strategy combined existing methods and legislation with innovative approaches and concepts of integrated pest management. This involved employing a range of techniques simultaneously and using adaptive management to incorporate growing knowledge. Possession of fish classified as noxious required a permit and was allowed only for educational or research purposes.

The focus of the strategy was on containing existing pest fish populations and minimising their impacts on native species, rather than trying to eradicate them altogether.

The current strategy (2011–2016) for controlling pest fish in Queensland is currently being developed and aims to increase stakeholder awareness while continuing the integrated pest management approach of the 2000–2005 strategy. Based on what has been learnt from past experiences (i.e. Stop the Spread campaign), community engagement is a significant management activity. It involves developing community support and actual on-ground engagement of members of the community in activities that can control current infestations and prevent new incursions. The goals of the current strategy are to:• increase community understanding of pest

fish and their management• develop effective partnerships to increase

capacity to manage impacts and control the spread of pest fish

• prevent the spread of pest fish species beyond known distributions in Queensland

• minimise the impacts of established populations of pest fish

• ensure that existing noxious and nonindigenous fish legislation is appropriate, adequately enforced and within national frameworks.

Figure 2.1 A brochure circulated around Queensland to educate the community about pest fish

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Module 2:Overview and history of pest fish management

species, which are now illegal to sell and possess. This listing ensures that retail trade of these species will cease, and removes ongoing risk of unwanted non-native species being released into waterways.

As part of an ongoing education campaign to raise awareness of the impacts of releasing fish into natural waterways, a series of advisory materials, including brochures and bookmarks (titled Don’t dump that fish!), have been widely distributed to members of the aquarium industry and the New South Wales community. To extend the reach of the campaign, bookmarks have been translated into five languages.

The introduction of fish into areas outside their natural range has been listed as a key threatening process under the Fisheries Management Act 1994; this means that formal assessment is required in development control processes established by the Environmental Planning and Assessment Act 1979. Unfortunately, once pest fish become established in a waterway it is often extremely difficult, if not impossible, to remove them. Most eradication efforts have focused on pest fish that are restricted to a very small area, such as speckled mosquitofish (Phalloceros caudimaculatus) at Long Reef in northern Sydney and Jack Dempsey cichlids (Cichlosoma octofasciatum) at Angourie on the New South Wales north coast.

Carp are recognised as a significant pest fish in New South Wales and in 2010, the New South Wales Government finalised the control plan for the noxious fish carp (Cyprinus carpio). The plan brings together the most up-to-date information about the biology and impacts of carp and outlines what is being done, or should be done, to stop further spread, control the size of populations and increase the understanding and involvement of the community.

New South Wales

The New South Wales Government approaches pest fish management through listing noxious fish (where required), and implementing survey, research, education, advisory and signage programs. The New South Wales Monitoring, Evaluation and Reporting (MER) Strategy was developed in 2006 to better understand changes in the overall health of natural resources. Surveillance for pest fish, as well as other research projects, is conducted under the current MER Strategy (2010–2015) and involves comprehensive statewide monitoring of native and non-native species. Control and eradication programs are implemented in New South Wales after both risk assessments and feasibility analysis are completed, and in limited situations only. Education and advisory programs regarding pest fish are a high priority, as these are considered key to preventing future incursions of new pest fish. In addition, the New South Wales Government seeks collaborative arrangements with local communities, local governments and external funding bodies to implement pest fish programs.

New South Wales legislation provides for listing of noxious fish species, which gives the government powers to seize and destroy Class 1 noxious fish. The New South Wales noxious fish list has recently been amended as a result of the government implementing aspects of the national strategy for the management of ornamental fish. This national strategy was developed in 2006 to provide consistent management of ornamental fish for commercial and hobbyist operations and of noxious ornamental fish species across the states and territories. As part of the implementation of this strategy, the New South Wales Government has now listed over 130 species as Class 1 noxious fish

Figure 2.2 Advisory material distributed throughout New South Wales photo courtesy of NSW DPI

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In addition to this, the national management strategy for carp control was developed by the Murray–Darling Basin Commission, now known as the the Murray–Darling Basin Authority (MDBA). The MDBA is also developing a Basin Alien Fish Plan as part of the native fish strategy for the Murray–Darling Basin (NFS). The NFS was developed to ensure that viable fish communities and populations are sustained throughout the rivers of the MDB. The control and management of pest fish is one of six driving actions of the NFS, which are:1. Rehabilitate fish habitat.2. Protect fish habitat.3. Manage river structures.4. Control pest fish.5. Protect threatened species.6. Manage translocation and stocking.

Pest fish management measures are also implemented by the Australian Quarantine and Inspection Service (AQIS) at the Australian border. AQIS is an operating group within the Department of Agriculture, Fisheries and Forestry (DAFF); it implements the List of permitted live freshwater fish suitable for import (the live import list) and the border controls that prohibit the importation of any live freshwater fish not included on the list (Appendix D). The list is established by the Department of the Environment, Water, Heritage and the Arts (DEWHA) as part of the Environment Protection and Biodiversity Conservation Act 1999. In addition to complying with the live import list, importers must obtain a permit to import live fish for ornamental purposes from AQIS before the arrival of the fish in Australia. Each consignment must be accompanied by health certification from the AQIS-approved competent authority in the exporting country and all ornamental fish are examined and quarantined at AQIS-approved premises for seven days. Fish are then examined by AQIS at the end of the quarantine period for signs of pests or disease before being released for on-sale.

All strategies for managing pest fish in Australia aim to support and complement each other by providing common goals and a consistent message to stakeholders. This ensures direction and focus for a uniform approach to pest fish management across Australia.

National

On a national level, the Ornamental Fish Management Implementation Group (OFMIG) was established in 2006 to implement the recommendations of the national strategy for the management of ornamental fish. One of the strategy’s recommendations is the creation of a national noxious fish list and ongoing assessment of ‘grey list’ species to determine future additions to the list. Grey list species were identified during the development of the national strategy as those ornamental fish not on the national noxious fish list that required further investigation/consideration and risk assessment to determine whether they warranted inclusion on the list. OFMIG includes representatives from all state and territory jurisdictions as well as from industry, the hobby sector and the Australian Government. The national group is involved in many ongoing activities, including the progression of the following key recommendations from the strategy:• develop a nationally agreed noxious

species list• develop control mechanisms for the

regulation and management of noxious fish• review and conduct risk assessment of all

grey list species• develop appropriate national communication

tools for implementation at a state/jurisdiction level to raise public awareness of the national strategy.

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Module 2:Overview and history of pest fish management

Although tilapia can be found in a variety of habitat qualities, they often flourish in disturbed wetland habitats, as these environments often have relatively abundant food resources (organic waste) and generally lack native fish competition because of harsh and changed physical conditions. Although populations of pest fish can act to accelerate the degradation of aquatic ecosystems, their presence can often be more correctly interpreted as a symptom of degraded water, rather than a cause. Therefore, pest fish control needs to be a part of an overall river rehabilitation process.

It is important to maintain well-functioning ecosystems with high diversities of native plants and animals. Native organisms have adapted to specifically interact with each other to create food webs and sustain the flow of energy from the primary producers (e.g. plants) up to the carnivorous animals. These important interactions can be maintained by reducing stressors (e.g. pollution and clearing) so that native fish species can maintain healthy populations. This will also help prevent new pest fish incursions and limit the impact of existing tilapia populations.

algae(primary producer)

(detritivore)common yabby

(primary consumer)

(carnivore)golden perch

(secondary consumer)

(carnivore)Murray cod

(tertiary consumer)

(detritivore/omnivore)tilapia

Figure 2.3 The impact of tilapia on a simple food chain within the MDB

Pest fish management and the broader river health and rehabilitation

Once a population of pest fish becomes established in a waterway, the natural flow of energy in the ecosystem becomes disrupted. Freshwater communities in the MDB are relatively simple, with few species at any one level of a food chain. This means that if the population of any one species becomes depleted, there may not be another similar species to take on that ecological role. The following figure shows a simple food chain within the MDB and the impact of introducing tilapia. Although tilapia primarily consume algae and other forms of detritus, they would also directly impact populations of organisms at other energy levels. This would then indirectly impact the numbers of tertiary consumers, such as Murray cod, by limiting important food sources.

Problems that need to be addressed in conjunction with pest fish control include:• flow regulation• habitat degradation (e.g. from cattle,

desnagging and pollution)• reduced water quality• barriers preventing fish passage

(e.g. dams and weirs)• exploitation (commercial and

recreational fishing)• disease• inappropriate translocation and stocking.

When planning pest fish eradications, it is important to avoid any method that might cause further major or irreversible harm to the environment, as this will leave the system vulnerable to further pest fish incursions.

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Degraded aquatic habitat

Figure 2.5 Cattle crossing directly through waterway photo courtesy of Charlotte Jenkins, NSW DPI

Figure 2.7 Clearing of vegetation around a waterway photo courtesy of Charlotte Jenkins, NSW DPI

Figure 2.9 Eroded riverbank

Intact aquatic habitat

Figure 2.4 Constructed cattle crossing photo courtesy of Charlotte Jenkins, NSW DPI

Figure 2.6 Well-vegetated waterway photo courtesy of Charlotte Jenkins, NSW DPI

Figure 2.8 Well-vegetated and stable riverbank

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Demonstration reaches have been put in place as part of a current plan to sustain native fish populations in the MDB. These are intended to show the community the benefits of applying a suite of well-integrated methods of river rehabilitation (e.g. provision of fish passage, resnagging and pest fish management) to conserve native fish populations. The establishment of a demonstration reach involves a range of individuals and community groups, thereby enhancing community awareness and support. A detailed long-term plan for a demonstration reach is developed along with on-ground activities, which are refined as successes and new challenges arise.

Figure 2.10 Conceptual diagram of a typical demonstration reach courtesy of Rucosky Noakes, T. (2010). Sustaining river life: a Years K-12 curriculum and activities guide for teachers and natural resource managers

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Importance of raising awarenessAlthough government can take a leading role in managing pest fish, successful control requires a partnership of all stakeholders. The importance of raising awareness and encouraging community involvement comes down to the facts that pest fish affect the whole community and that incursions are often facilitated by the actions of uninformed members of the public.

The government currently relies on the community to report new sightings of tilapia; this allows for an early response before new breeding populations can be established. This level of community involvement is not always effective, however, as there can be confusion about the identification of fish that are caught or sighted.

The public’s knowledge of pest fish is generally limited; the issue is often complicated by those who actually encourage and promote the use of pest fish resources. For example, tilapia is a popular food fish in many Asian and African countries and their suitability as a table fish is often promoted. Despite the existence of legislation prohibiting the possession and release of tilapia in Queensland, cases still exist where individuals purposely stock aquariums, dams, ponds or waterways for ornamental purposes or personal use/consumption. Such individuals may be aware of the legislation; however, the specific reasons for the legislation or the implications of their actions often remain unclear to them.

Communication materials such as brochures, posters and pamphlets can be distributed more widely to spread current knowledge on pest fish and make people aware of the implications of their actions. Updated educational material has recently been developed to help raise awareness in this area.

The most effective approach to tackling the issue of pest fish will be to encourage the participation of all stakeholder groups in regional and local management actions. A multi-stakeholder partnership is the best way to use and enhance the limited resource base allocated to pest fish control. Raising community awareness is important to achieve this, so that people know:• the extent of the pest fish problem• how it affects them• what they can do to prevent new incursions• how they can contribute to the management

of existing pest fish populations.

Limitations to pest fish controlThere is no ‘silver bullet’ for eradicating pest fish. Once a pest fish population is well established in a large or uncontained waterway, eradication is very difficult and often not achievable with the technology currently available. Current eradication methods are limited to physical removal, draining and pesticides. These methods can be useful for enclosed bodies of water; however, they are generally not long-term solutions to pest fish infestations on a larger scale. Unless carefully implemented, eradication attempts can cause more environmental harm than good.

With this in mind, management measures are more beneficial and practical if they concentrate on containing noxious species within their present range and on spot-removal of new infestations, where possible and where eradication is likely to be successful.

Most previous efforts at pest fish control have not specifically sought to involve community stakeholders. Pest fish are an increasing problem in Australia, with new infestations thought to be due mainly to the actions of uninformed members of the community. There is widespread ignorance among the community of the problems associated with pest fish incursions and how they occur. Governments have realised that they do not have the capacity to tackle Australia’s pest fish problem alone and that responsibility lies with the community as a whole.

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Case studies

Stop the spreadThe 2007 Stop the Spread campaign was a particularly successful project to tackle the tilapia infestation in North Queensland. The campaign involved the delivery of targeted communication aimed at limiting the spread of tilapia by people moving them between waterways. This approach was used after successful eradication was deemed highly unlikely due to the extent of the infestation in large flowing waterways. Key messages communicated to the public included: • the dos and don’ts (i.e. don’t use tilapia as bait and don’t move tilapia between waterways)• how to identify tilapia• where to report an infestation• why tilapia are a pest• why eradication is not an option.

To deliver the key messages, materials such as brochures, posters, activity books, mobile displays and pamphlets for letterbox drops were distributed to schools, councils, recreational fishers, aquarium owners and other community members. Meetings and community events were also held. The result of this campaign was positive, with the community becoming more aware of facts and engaging in cooperative actions to resolve the issue and stop the spread.

Educational material used in the 2007 Stop the Spread campaign

Eureka CreekAlthough the successful eradication of established populations of tilapia is rare, in some circumstances eradication is a viable option. In 2008, a new incursion of tilapia was discovered in Eureka Creek, south-west of Cairns. This creek is part of the Mitchell River catchment, which flows into the Gulf of Carpentaria. After thorough surveys and consideration of the management options available, it was determined that the most appropriate action was to treat the defined section of the creek with the poison rotenone. The application of rotenone resulted in the elimination of the tilapia population, with only minimal, short-term impacts on native species. Extensive post-eradication monitoring and surveillance of the creek revealed no further presence of tilapia. In this case, the implementation of an eradication method was successful in preventing tilapia from entering the Mitchell River catchment and the Gulf of Carpentaria.

Rotenone being applied to Eureka Creek, Queensland, to eradicate tilapia

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Long Reef Golf CourseThe speckled mosquitofish (Phalloceros caudimaculatus) is a small, hardy livebearer that was discovered in ponds that form the water hazards at Long Reef Golf Course in northern Sydney in 2002. The nearest known wild population of this species is 1600 km away, which indicates that

the most likely vector of introduction was release from a home aquarium. Eradication of the species from the golf course ponds was attempted in 2002 using rotenone, and although a considerable population reduction was achieved, the attempt was unsuccessful, highlighting the hardy nature of the species. A second eradication attempt using rotenone was undertaken in June 2006, and follow-up monitoring of the ponds over two subsequent years has confirmed that this eradication attempt was successful and that the fish are no longer present.

The speckled mosquitofish (Phalloceros caudimaculatus) photo courtesy of Dale McNeil, SARDI Aquatic Sciences

Brewarrina to Bourke Demonstration ReachThe Brewarrina to Bourke Demonstration Reach project was a collaborative agreement between the Western Catchment Management Authority and Industry & Investment New South Wales. The project aimed to enhance native fish habitat in the 207 km stretch of the Barwon–Darling River between Brewarrina and Bourke, north-western New South Wales, through on-ground works and community awareness activities. The project involved:• remediation of barriers to fish passage• reintroduction of large woody habitat (snags)• targeted riparian vegetation program within selected reaches, including revegetation and weed

management• carp management and ‘outback carp muster’ events• erosion control and gully stabilisation• protection of riparian vegetation through fencing and stock access control.

Planned outcomes from the combination of these on-ground activities included:• improved aquatic habitat condition of the Barwon–Darling River• improved river health in priority areas as indicated by aquatic biodiversity and prevalence of

aquatic species• a contribution to the recovery of species, populations and communities listed as threatened

in either state or Commonwealth law.

One of the most significant outcomes will be the construction of a fishway on Brewarrina Weir. Fishways, also known as fish ladders or fish passes, are structures placed on or around constructed barriers (such as dams or weirs) to give fish the opportunity to migrate. Fish undertake migrations for a number of reasons including to spawn, feed and seek refuge. The new fishway will allow fish uninterrupted access to a 324 km reach of the Barwon–Darling river system.

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Module 2:Overview and history of pest fish management

Learning activitiesImporting fish

Purpose: To assess whether participants understand how the legislation applies to a real-life scenario and to prompt them to think about the legal requirements in real-life situations.

Scenario: Mr Guppy is the manager of Scales ‘R’ Us, a new and upcoming Australian aquarium store for rare and exotic ornamental fish enthusiasts. He has recently heard of a new fish species that has become a very popular aquarium fish in America: the hairy-backed gobbler. Mr Guppy did some research on the hairy-backed gobbler and discovered it was native to Tunisia, very easy to look after and available in a variety of vibrant colours and patterns.

The hairy-backed gobbler appears to be the perfect addition to Scales ‘R’ Us. Unfortunately Mr Guppy would have to import the fish from either America, or direct from Tunisia.

Questions: What steps should Mr Guppy take in order to see if he can import some hairy-backed gobbler individuals into Australia for sale in his store? What are some of the reasons that would prevent him importing this fish into Australia?

AnswerMr Guppy would have to consult the AQIS List of permitted live freshwater fish suitable for import, which can be accessed online at <www.daff.gov.au/aqis>. If the hairy-backed gobbler is allowed to be imported into Australia (according to the list), Mr Guppy would then have to check that Tunisia is an approved country for aquarium fish importation. Mr Guppy can contact AQIS directly on 1800 020 504 or (02) 6272 3933. It is important that Mr Guppy check that the list is current at the time of importation as only fish appearing on the list on the day of import will be eligible for entry into Australia. In addition to this, Mr Guppy would also have to check that the hairy-backed gobbler is not listed as noxious in the state where he is planning to sell the fish. Finally, Mr Guppy would have to ensure that he has all the relevant certificates and import permits to accompany his consignment.

River health and rehabilitation

Purpose: To ensure participants understand how pest fish management fits in with the broader river health and rehabilitation and how maintaining healthy ecosystems can prevent pest fish incursions.

Discuss among the group how restoring aquatic ecosystems could indirectly control tilapia numbers. What are some actions that could be taken to restore a disturbed aquatic ecosystem?

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4. A demonstration reach is:a) A stretch of river that is used to show

how rehabilitation can be achieved by a suite of well-integrated actions

b) A stretch of river that is used to show how the management of pest fish alone can rehabilitate an aquatic environment

c) A stretch of river that is used to show how pest fish can degrade aquatic environments

d) A stretch of river that contains no pest fish

5. Once a pest fish population is well established in a large or uncontained waterway:a) Eradication via physical removal (i.e.

line fishing) is the only optionb) Eradication is very difficult and often

not achievable with the technology currently available

c) Eradication is still achievable in most cases, thanks to the technology currently available

Answers

1. b) The dos and don’ts (i.e. don’t use tilapia as bait and don’t move tilapia between waterways); how to identify tilapia; how to report an infestation; why tilapia are a pest; and why eradication is not an option

2. d) Should take a multi-stakeholder and uniform approach across Australia

3. b) Animals at all levels of the food chain

4. a) A stretch of river that is used to show how rehabilitation can be achieved by a suite of well-integrated actions

5. b) Eradication is very difficult and often not achievable with the technology currently available

Quiz1. The key messages of the 2007 Stop the

Spread campaign in North Queensland included:a) The dos and don’ts (i.e. don’t use tilapia

as bait and don’t move tilapia between waterways); how to identify tilapia; how to report an infestation; why tilapia are a pest; and how to eradicate tilapia

b) The dos and don’ts (i.e. don’t use tilapia as bait and don’t move tilapia between waterways); how to identify tilapia; how to report an infestation; why tilapia are a pest; and why eradication is not an option

c) The dos and don’ts (i.e. do use tilapia as bait and don’t move tilapia between waterways); how to identify tilapia; how to catch tilapia; why tilapia are a pest; and how to eradicate tilapia

d) The dos and don’ts (i.e. do use tilapia as bait and don’t move tilapia between waterways); how to identify tilapia; how to catch tilapia; and why eradication is not an option

2. Pest fish management:a) Is up to state governments to implement

aloneb) Should be implemented by each state

separately with independent goals and messages

c) Should focus mostly on carp, as they are the most abundant pest fish species in Australia

d) Should take a multi-stakeholder and uniform approach across Australia

3. The introduction of tilapia in the Murray–Darling Basin would impact on:a) Only primary producers, such as algaeb) Animals at all levels of the food chainc) Animals at all levels of the food chain,

except the top predators such as the Murray cod

d) Only the primary producers (e.g. algae) and primary consumers (e.g. yabbies)

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Module 2:Overview and history of pest fish management

How can I get involved in local demonstration reach projects?If you enjoy fishing, are interested in native fish rehabilitation and river restoration, or think your local area would suit a native fish demonstration reach, the MDBA would like to hear from you. Please contact MDBA by phoning (02) 6279 0100 for further information and to obtain the contact details for your nearest Native Fish Strategy Coordinator.

Why doesn’t the government just eradicate every pest fish population that is discovered?Eradication of pest fish species using currently available technology is rarely possible once breeding populations have become established. Therefore, priority is given to preventing further spread.

FAQsWhere can I get copies of pest fish communication material such as brochures, cards, leaflets, activity books and posters?Contact the DEEDI Customer Service Centre on 13 25 23 or NSW DPI on (02) 4982 1232.

Where can I get copies of the strategies and other publications mentioned in this module?Queensland strategies and publications are available from <www.fisheries.qld.gov.au> or call DEEDI on 13 25 23.

New South Wales strategies and publications are available from <www.dpi.nsw.gov.au> or call NSW DPI on (02) 4982 1232.

The native fish strategy for the Murray–Darling Basin is available from <www2.mdbc.gov.au/NFS> or call the MDBA on (02) 6279 0100.

The national strategy for ornamental fish is available from <www.dpi.nsw.gov.au> or call DAFF on (02) 6272 5120.

The national management strategy for carp control 2000–2005 is available from <publications.mdbc.gov.au>.