Silver Perch (Bidyanus bidyanus) ***


In accordance with section 21 of the Nature Conservation Act 1980, the Silver Perch (Bidyanus bidyanus) was declared an endangered species on 4 September 2001 (Instrument No. 192 of 2001). Section 23 of the Act requires the Conservator of Flora and Fauna to prepare an Action Plan in response to each declaration. This is the Action Plan for the:


The Nature Conservation Act 1980 establishes the ACT Flora and Fauna Committee with responsibilities for assessing the conservation status of the ACT’s flora and fauna and the ecological significance of potentially threatening processes. Where the Committee believes that a species or ecological community is threatened with extinction or a process is an ecological threat, it is required to advise the Minister for the Environment, and recommend that a declaration be made accordingly.

Flora and Fauna Committee assessments are made on nature conservation grounds only and are guided by specified criteria as set out in its publication ‘Threatened Species and Communities in the ACT’, July 1995.

In making its assessment of the Silver Perch, the Committee concluded that it satisfied the criteria indicated in the adjacent table.

An Action Plan is required in response to each declaration. It must include proposals for the identification, protection and survival of a threatened species or ecological community, or, in the case of a threatening process, proposals to minimise its effect.

The Flora and Fauna Committee will conduct an evaluation of the progress made in implementing this Action Plan every three years (see page 9 for details). This is due to first take place in 2004, which will bring it in line with the review of progress in implementing Action Plans for other declared aquatic items.

While the legal authority of this Action Plan is confined to the Australian Capital Territory, management considerations are addressed in a regional context.

Criteria Satisfied

1.2 The species is observed, estimated, inferred or suspected to be at risk of premature extinction in the ACT region in the near future, as demonstrated by:

1.2.1 Current severe decline in population or distribution from evidence based on: Direct observation, including comparison of historical and current records. Severe decline in rate of reproduction or recruitment; severe increase in mortality; severe disruption of demographic or social structure. Very high actual or potential levels of exploitation or persecution. Severe threats from herbivores, predators, parasites, pathogens or competitors.

Links with other Action Plans

Measures proposed in this Action Plan complement those included in the Action Plans for other threatened aquatic species, such as the Two-spined Blackfish (Gadopsis bispinosus), Trout Cod (Maccullochella macquariensis) Macquarie Perch (Macquaria australasica) and Murray River Crayfish (Euastacus armatus). Action Plans are listed at the end of this document.

Species Description and Ecology

The Silver Perch Bidyanus bidyanus is a member of the family Terapontidae, which contains the freshwater grunters or perches. The family contains a total of about 22 species in eight genera in Australian freshwaters, of which one species, the Silver Perch, is found in the ACT and surrounding area. The majority of terapontids occur in northern Australian streams.


B. bidyanus is a moderate to large fish (maximum length of about 500 mm and a maximum weight of around 8 kg) which commonly reaches 300-400 mm and 0.5-1.5 kg in rivers (Figure 1). The body is elongate and slender in juvenile and immature fish, becoming deeper and compressed in adults. The head is relatively small, jaws are equal in length, and eyes and mouth are small. The scales are thin and small (compared to Macquarie Perch or Golden Perch) and the tail is weakly forked. The lateral line follows the profile of the back. Colour is generally silvery grey to black on the body, with the dorsal, anal, caudal fins also grey. The pelvic fins are whitish (Merrick 1996, Merrick & Schmida 1984).


B. bidyanus is found over a broad area of the Murray-Darling Basin and is often found in similar habitats to Murray Cod (Maccullochella peelii) and Golden Perch (Macquaria ambigua), ie. lowland, turbid rivers. There are some reports that suggest that B. bidyanus prefers faster, open water, but the general scarcity of information on the habitat preferences of the species makes generalisation difficult. The species is not found in the cool, fast-flowing, upland rivers of the Murray-Darling Basin.


B. bidyanus is slow-growing and long-lived in rivers, with a greatest age of 17 years recorded from the Murray River and 27 years recorded from Cataract Dam. A 1.4 kg fish could be 17 years old (Mallen-Cooper et al. 1995, 1997). Growth rates in dams are much faster with a 2.3 kg fish from Googong Reservoir being approximately 6 years old (M. Lintermans unpublished data).

B. bidyanus matures at 3–5 years and spawn in spring and summer after an upstream migration. They school in large numbers during the upstream migration and research conducted at Torrumbarry Weir demonstrated that large numbers of immature fish were part of this migration (Mallen-Cooper et al. 1997).

This species is bred artificially in a number of government and commercial hatcheries and is widely stocked in farm dams and reservoirs, however, it rarely breeds in impoundments. The species is currently the subject of considerable interest in terms of its potential as an aquaculture species (Kibria et al. 1998).

B. bidyanus is omnivorous, consuming aquatic plants, snails, shrimps and aquatic insect larvae. Reports that the species becomes mainly herbivorous once they reach lengths of 250 mm are incorrect, at least for lake populations, as their diet in Googong Reservoir shows little change with fish size (M. Lintermans unpublished data).


Formerly widespread over much of the Murray Darling Basin (excluding the cooler upper reaches), the species has declined over most of its range. Numbers of B. bidyanus moving through a fishway at Euston Weir on the Murray River have declined by 93% between 1940 and 1990 (Mallen-Cooper 1993). The ACT probably represented the upstream limit of the species distribution in the Murrumbidgee catchment, but it could not be considered as a vagrant because it was a regular component of the recreational fishery.

In the Canberra region the species has been recorded from the Murrumbidgee River where numbers recorded in a fish trap at Casuarina Sands between 1980 and 1991 declined noticeably from the mid 1980s (Lintermans 2000). Monitoring of the Murrumbidgee fishery in the ACT since 1994 has failed to capture

any B. bidyanus (Lintermans 1995, 1997, 1998). In the last decade there have been a small number of angler reports of B. bidyanus from the Murrumbidgee River in the ACT.

Formerly a ‘run’ of B. bidyanus from Lake Burrinjuck migrated upstream to the lower reaches of the Murrumbidgee River in the ACT in spring/summer, but this migration has not been recorded since the late 1970s/early 1980s (Lintermans 2000). In the ACT, B. bidyanus has not been recorded further upstream than Kambah Pool (Lintermans 2000). There have been occasional angler reports of B. bidyanus from the Murrumbidgee River at Bredbo, but these are thought to have originated from releases into local farm dams.

Greenham (1981) reported anecdotal angler records of B. bidyanus from the Molonglo River in the 1940s and 1950s but no contemporary records are known from this river (other than stocked fish). There are no records of the species from the Paddys, Naas, or Gudgenby Rivers. There are occasional angler records of B. bidyanus from the Queanbeyan River below Googong Reservoir but these fish are assumed to be stocked fish displaced downstream from the reservoir.

In the Canberra region B. bidyanus is also known from four other locations. These are:

  • a stocked population in Googong Reservoir on the Queanbeyan River;
  • a stocked population in the Yass weir pool on the Yass River;
  • a stocked population in Lake George; and
  • a population of unknown size in Burrinjuck dam (which is supplemented/maintained by stocking by NSW Fisheries).

B. bidyanus is also regularly stocked into farm dams by land‑holders in the Canberra region.

Conservation Status

B. bidyanus is recognised as a threatened species in the following sources:


In August 2000, the Australian Society for Fish Biology Threatened Fishes Subcommittee listed B. bidyanus as nationally ‘vulnerable’ (under ASFB categories) and ‘endangered’ (under IUCN categories). However, there has been no formal nomination of B. bidyanus as a threatened species under the Commonwealth Environment Protection and Biodiversity Conservation Act 1999.

A Recovery Plan for the species was prepared by Clunie and Koehn (2001a) for the Murray-Darling Basin Commission. The plan recommends that the species may satisfy the criteria to be classified as ‘Critically Endangered’ under the IUCN categories.

Australian Capital Territory

Endangered—Section 21 of the Nature Conservation Act 1980, Disallowable Instrument No. 299 of 2001.

Special Protection Status Species—Schedules 6 and 7 of the Nature Conservation Act 1980, Disallowable Instrument No. 42 of 2002.

New South Wales

Vulnerable—Schedule 5 of the Fisheries Management Act 1994 in NSW.


Threatened taxon—Schedule 2 of the Flora and Fauna Guarantee Act 1988.

Cadwallader et al. (1984) listed B. bidyanus as ‘Vulnerable’ in Victoria and this categorisation was retained by Koehn and Morison (1990) when they reviewed the conservation status of Victorian fish. The species is currently listed as critically endangered in Victoria (NRE 2000).


The species is considered 'insufficiently known' in Queensland (Wager 1993).

Threats to Populations in the ACT Region

Alteration or destruction of fish habitat is widely regarded as one of the most important causes of native fish decline in Australia (Cadwallader 1978; Koehn and O'Connor 1990a,b; Lintermans 1991a; Hancock 1993) and overseas (Moberly 1993; Maitland 1987). The impacts of introduced fish species are also considered to have had an impact on populations of B. bidyanus nationally and locally. However, the specific contributions of these impacts to the species’ decline are not well understood as the threats are likely to have acted in concert.

In an exercise to rank the threats to B. bidyanus, the members of the national recovery team considered the top three threats to the species were alteration of flow regimes, barriers to fish movement, and introduced species (Clunie & Koehn 2001b).


The construction of dams has a severe effect on the quality of fish habitat through the modification of the natural flow regimes and water quality of rivers below impoundments. The effect of some impoundments (e.g. Corin Reservoir and Lake Burrinjuck) on downstream river flows is to partially reverse the seasonal nature of flows as water from spring and autumn rains is collected and stored for release in summer.

Other impoundments such as Bendora, Cotter and Googong reservoirs and Lake Burley Griffin have a different impact in that insufficient water is released to maintain suitable environmental conditions in the river downstream.

The quality of water released is also a problem in that it may be released from the lower levels of the reservoir and is much colder than the surface waters. The release of a cold slug of water during the breeding season is thought to inhibit spawning behaviour of B. bidyanus and other native fish species.

The large areas of still water created by dams may also impact egg and early larval stages of B. bidyanus. The drifting semi-buoyant eggs and newly hatched larvae may settle in unfavourable habitats such as the backed up waters of dams and weir-pools, making them susceptible to sedimentation and low oxygen levels.


Construction of dams and weirs prevents recolonisation of streams by preventing fish passage. Consequently, the construction of Burrinjuck dam in the early 1900s effectively isolated the upper Murrumbidgee catchment from downstream B. bidyanus populations. Similarly the construction of Lake Burley Griffin in 1963 isolated the Molonglo and Queanbeyan rivers from the Murrumbidgee River and has prevented any recolonisation.


The establishment of introduced fish species is often cited as a cause of native fish decline in Australia, although much of the evidence is anecdotal. This is because the majority of introduced species became established in the mid to late 1800s when the distribution and abundance of native fish was poorly known or documented. Introduced fish species such as Carp (Cyprinus carpio) and Redfin Perch (Perca fluviatilis) have only recently become established in the Canberra region (Lintermans et al. 1990, Lintermans 1991b) and may compete for food with B. bidyanus, and P. fluviatilis may prey on juveniles of B. bidyanus.

Another potentially serious impact of introduced species is their capacity to introduce or spread foreign diseases and parasites to native fish species. C. carpio or P. fluviatilis are considered to be the source of the Australian populations of the parasitic copepod Lernaea cyprinacea (Langdon 1989a). C. carpio, Goldfish (Carassius auratus) or Eastern Gambusia (Gambusia holbrooki) are implicated as the source of the introduced tapeworm Bothriocephalus acheilognathi which has recently been recorded in native fish species (Dove et al. 1997). This tapeworm causes widespread mortality in juvenile fish overseas.

The most serious threat from introduced fish species to B. bidyanus may lie in the impacts of an exotic disease Epizootic Haematopoietic Necrosis Virus (EHNV). This virus, unique to Australia, was first isolated in 1985 on the introduced fish species P. fluviatilis (Langdon et al. 1986). It is characterised by sudden high mortalities of fish displaying necrosis of the renal haematopoietic tissue, liver spleen and pancreas (Langdon and Humphrey 1987).

Experimental work by Langdon (1989a,b) demonstrated that B. bidyanus was one of several species found to be extremely susceptible to the disease. EHNV was first recorded from the Canberra region in 1986 when an outbreak occurred in Blowering Reservoir near Tumut (Langdon and Humphrey 1987). Subsequent outbreaks have occurred in Lake Burrinjuck in late 1990, Lake Burley Griffin in 1991 and 1994, Lake Ginninderra in 1994 and Googong Reservoir, also in 1994 (Lintermans 2000). Its relatively resistant characteristics and the ease with which it can be transmitted from one geographical location to another on nets, fishing lines, boats and other equipment have aided the spread of EHNV. Langdon (1989b) found that the virus retained its infectivity after being stored dry for 113 days. Once EHNV has been recorded from a water body it is considered impossible to eradicate.

The Murrumbidgee and the Googong Reservoir populations of B. bidyanus have been exposed to the virus.

Reduction of instream habitat

In the ACT there has been little direct removal of instream habitat (such as the removal of logs from rivers and channelisation) as has occurred in lowland streams. Indirect causes of instream habitat reduction include sedimentation, clearing of riparian vegetation and the narrowing of stream channels below impoundments. Streams are often narrower and shallower below dams because of the storage capacity of the impoundments.

Reduction in water quality

The major reductions in water quality which are most likely to have affected the species in the Canberra region are sediment addition and changes to thermal regimes, either from the operation of impoundments or the clearing of riparian vegetation which shades streams.

Major Conservation Objectives

The major conservation objective of this Action Plan is to maintain in the long term, viable, wild populations of B. bidyanus as a component of the indigenous biological resources of the ACT and as a contribution to regional and national conservation of the species. This includes the maintenance of the species’ potential for evolutionary development in the wild.

The objective is to be achieved through the following strategies:

  • Improving understanding of the biology and ecology of the species as the basis for managing its habitat.
  • Protecting sites and habitats that are critical to the survival of the species.
  • Managing activities in the Murrumbidgee catchment in the ACT to minimise or eliminate threats to fish populations.
  • Increasing community awareness of the need to protect fish and their habitats.

Conservation Issues and Intended Management Actions


Habitat Rehabilitation

The majority of riverine ecosystems in eastern Australia have been affected by human impact with a resultant substantial modification of aquatic habitats. Significant effects on the rivers of the ACT region include irrigation extraction, dam construction and agricultural practices. Poor land management practices in the mid to late 1800s in the upper Murrumbidgee catchment resulted in extensive soil erosion and sediment addition to rivers. Also, clearing of the riparian zone removed nearly all the large eucalypts which were previously common, hence there remains no source of large woody debris (snags) to provide structural complexity and habitat diversity for both fish and invertebrate populations.

  • Environment ACT will investigate options for rehabilitating critical fish habitats. These options include the selective removal of sand to restore critical pool/riffle habitats and provision of additional cover such as snags or boulders.
  • Environment ACT will investigate mechanisms for rehabilitating and improving the protection of riparian vegetation along the Murrumbidgee River in the ACT.

Rehabilitation of fish habitat is costly and therefore requires a significant commitment of funds. Environment ACT will seek opportunities to secure external funding partnerships.

Environmental Flows

Increasing attention worldwide is being focussed on the need to provide water allocations for the environment. When the three impoundments on the Cotter River were constructed, little thought was given to how the abstraction or diversion of water would affect the animals living in the river. It is now known that to stimulate breeding activity, many native fish species require environmental stimuli or triggers such as an increase in water flow and water temperature. Reservoirs have severely disrupted downstream flow and temperature patterns, with consequent deleterious impacts for fish communities.

To address these issues, the ACT Government has developed Environmental Flow Guidelines that prescribe minimum flows to be achieved in the Cotter River above and below Bendora Reservoir, and include provisions for baseline flows as well as providing higher flows in spring to encourage fish spawning. ActewAGL is responsible for the operation of ACT water supply reservoirs and the release of water from them.

Provision of additional water and a more natural flow regime under the Environmental Flows Guidelines should contribute to enhanced fish habitat in the Cotter and downstream reaches of the Murrumbidgee River.

  • Environment ACT will liaise with ActewAGL to ensure that the appropriate flows under the Environmental Flows Guidelines are released from storages operated by the company.


Knowledge of the distribution of B. bidyanus in the upper Murrumbidgee catchment is largely complete. However, the status of the Lake Burrinjuck population has not been assessed since the mid 1980s when concerns were expressed about the impacts of an expanding P. fluviatilis population (Burchmore and Battaglene 1990). As the ACT B. bidyanus population is thought to be largely dependent on the status of the Lake Burrinjuck population, further investigations in Lake Burrinjuck are necessary to place the ACT population into a regional context.

  • Environment ACT (Wildlife Research and Monitoring (WR&M)) will liaise with NSW Fisheries about the possibility of assessing the status of the Lake Burrinjuck B. bidyanus population.


The decline of B. bidyanus in the Murrumbidgee River raises concerns about the long-term viability of this population. A long-term monitoring program capable of detecting changes in distribution and abundance of the species, which are outside the normal variation expected in these parameters in natural populations, is required.

  • Environment ACT (WR&M) will continue to monitor the fish population in the Murrumbidgee River in the ACT. Monitoring techniques will include those suited to detecting the presence of B. bidyanus.
  • Environment ACT (WR&M) will liaise with Victorian and NSW fisheries agencies to ensure that there is exchange of relevant information on the species.


There is some existing information on the biology and ecology of B. bidyanus, (Mallen-Cooper 1994; Gehrke 1990; Guo et al. 1995; Lake 1967a,b; Reynolds 1983) although much of the information remains unpublished. Diet, movement and reproduction have all been studied to some degree, but many studies are conducted in aquaculture ponds or laboratories, with few ‘wild’ studies available (see Barlow et al. 1987; Rowland et al. 1983; Allan & Rowland 1992). However, there are still some critical knowledge gaps which need addressing.

Effects of Introduced Carp

and Redfin Perch

The effects of introduced C. carpio and P. fluviatilis on B. bidyanus (and many other native fish species) is unknown. Increasing C. carpio abundance is often correlated with decreasing aquatic macrophyte abundance and other food chain alterations such as reduced zooplankton and increased phytoplankton. How such ecosystem alterations affect native fish species warrants further investigation.

Effects of EHN Virus in the Wild

P. fluviatilis in the Canberra region is known to be infected with EHN Virus. This virus has been shown to infect B. bidyanus in laboratory experiments but there have been no studies of how this virus affects wild populations.

  • Environment ACT will encourage research into a number of priority areas with key information gaps. These include effects of introduced C. carpio and P. fluviatilis, and effects of EHN Virus in the wild.


Large sections of the general community are unaware of the reasons for the decline of native fish, and the actions that can help to halt this. Provision of such information will enhance community understanding and engender community support for research and management actions. Options for providing this information include the Internet (Environment ACT Website), development of curriculum materials, as well as pamphlets and signs.

Some anglers either cannot, or choose not to discriminate between threatened and non-threatened fish species. Consequently some individuals of threatened species are not returned unharmed to the water after accidental capture. On-site identification aids at locations where threatened fish are likely to be caught may reduce the incidence of mis-identification of threatened fish species. Environment ACT has provided signage along the Murrumbidgee and Cotter rivers in the ACT to assist anglers identify other threatened fish species.

  • Environment ACT will investigate options for the provision of information to the public on the reasons for fish declines. The most appropriate and effective measures will be implemented where possible.
  • Environment ACT will investigate how to incorporate information on B. bidyanus into the existing threatened fish signage. The most appropriate and effective measures will be implemented where possible.


Overfishing is cited as one of the contributing factors in the decline of several native Murray-Darling fish species such as Trout Cod (M. macquariensis)(Douglas et al. 1994; Berra 1974) and Murray Cod (M. peelii peelii) (Rowland 1989; Jackson et al. 1993) and Macquarie Perch (M. australasica) (Cadwallader 1978; Harris and Rowland 1996).

Overfishing is unlikely to have played a major initial role in the decline of B. bidyanus, either nationally or locally. However, once a population has declined, even relatively low levels of fishing can pose a threat to recovery of the species. There is anecdotal evidence that local anglers targeted the spawning run of B. bidyanus from Lake Burrinjuck. The current protective management regimes by NSW Fisheries (which prohibits the taking of B. bidyanus in rivers and imposes bag and size limits in dams) and Environment ACT (which prohibits the taking of B. bidyanus in any public waters) are considered appropriate.

  • Environment ACT will continue to prohibit the taking of B. bidyanus in public waters until the local population has recovered to levels which are assessed to be capable of sustaining recreational harvest.
  • Environment ACT (WR&M) will continue to liaise with NSW Fisheries to ensure that the there is consistency in the relevant fishing regulations for B. bidyanus.


Hatchery-bred fish used in fish stocking programs are usually derived from a small number of brood fish, and so may lack the normal range of genetic variation present in wild populations. An investigation into the genetic variability of B. bidyanus in rivers and dams within the Murray-Darling Basin has revealed that stocked populations have less genetic diversity than wild populations (Keenan et al. 1996). The introduction of hatchery-bred fish into remnant wild populations may lead to reduced genetic variability in the population as a whole, and reduce its adaptive capacity.

The remnant population of B. bidyanus in Lake Burrinjuck has been augmented with hatchery-bred fish for many years, and it is unknown whether ‘wild’ levels of genetic diversity remain in this population. The ACT Government does not stock streams for recreational purposes, preferring to concentrate its stocking program on lakes and dams (ACT Government 2000). There is provision for stocking streams for conservation purposes, but only when strict criteria are satisfied.

  • Environment ACT will encourage investigations into the identification of genetic composition of the Lake Burrinjuck population of B. bidyanus.
  • Environment ACT will not consider stocking B. bidyanus into the Murrumbidgee River in the ACT until the status and genetic composition of the Lake Burrinjuck population is known.


A recent review of the conservation status of fish in the Murray-Darling Basin has proposed that B. bidyanus be listed as nationally endangered under the Environment Protection and Biodiversity Conservation Act 1999 (Morris et al. 2001). It is likely that the species will be formally nominated for this status in the near future.

  • Environment ACT will support the listing of B. bidyanus as endangered under the EPBC Act.


Before its declaration as an endangered species in the ACT, B. bidyanus was unprotected. In a review of recreational fishing in the ACT (ACT Parks and Conservation Service 1995), it was proposed to create a dedicated Fisheries Officer position in an effort to curb illegal fishing and better protect the ACT’s fish resources. This proposal received widespread public support (ACT Parks and Conservation Service 1996) and the ACT Government now has a dedicated fisheries officer.

Socio-economic Issues

The main social benefit of conserving representative populations of B. bidyanus is meeting community concerns that further loss or extinction of native species is prevented.

Management of the Cotter catchment for conservation of threatened fish species, including provision of environmental flows, has previously been of concern to ActewAGL in terms of the security of water supply and pricing of domestic water. Compliance with the Environmental Flow Guidelines may have some impact on the urban water supply potential of the Cotter catchment. This may result in greater use of the higher cost water from Googong Dam which currently supplements water supply from the Cotter catchment during periods of high demand.

Legislative Provisions

The following legislation is relevant to conservation of flora and fauna in the ACT region:


Nature Conservation Act 1980

The Nature Conservation Actprovides a mechanism to encourage the protection of native plants and animals (including fish and invertebrates), the identification of threatened species and communities, and the management of Public Land reserved for nature conservation purposes. Specified activities are managed via a licensing system.

Native plants and animals may be declared in recognition of a particular conservation concern and increased controls and penalties apply. Species declared as endangered must be declared as having special protection status (SPS), the highest level of statutory protection that can be conferred.

As an endangered species, B. bidyanus must be declared a SPS species and any activity affecting such a species is subject to special scrutiny. Conservation requirements are a paramount consideration and only activities related to conservation of the species or serving a special purpose are permissible. The Conservator of Flora and Fauna may only grant a licence for activities affecting a species with SPS where satisfied that the act specified in the licence meets a range of stringent conditions. Further information can be obtained from the Licensing Officer, Environment Regulation, Environment ACT, telephone (02) 6207 6376.

Fisheries Act 2000

The new Fisheries Act 2000 is consistent with the corresponding NSW fishing legislation. The Act now has adequate provisions to protect native fish species by providing for bag, size and gear limits as well as being able to declare closed seasons or total protection for fish species.

Land (Planning and Environment) Act 1991

The Land (Planning and Environment) Act 1991 is the primary authority for land planning and administration. It establishes the Territory Plan, which identifies nature reserves, national parks and wilderness areas within the Public Land estate.

The Territory Plan also provides for flora and fauna guidelines which list criteria for the assessment of the potential impact of a land use proposal. These focus on a range of aspects of the ACT’s ecological resources, including the protection of vulnerable and endangered species along with their habitats. The conservation requirements of threatened species and their habitats are considered specifically during this process.

The Act also establishes the Heritage Places Register. Places of natural heritage significance may be identified and conservation requirements specified.

Environmental Assessments and Inquiries may be initiated in relation to land use and development proposals.


Fisheries Management Act 1994

The Fisheries Management Act 1994 includes provisions covering the identification, assessment and listing of endangered species, populations and ecological communities, vulnerable species and key threatening processes. They also provide for identification of critical habitat, mandatory impact assessment in the land use planning process and active recovery management.

Consultation and Community Participation

In 1995, a discussion paper on recreational fishing in the ACT was widely circulated for public comment (ACT Parks and Conservation Service 1995). The purpose of the paper was to outline current fisheries management in the ACT and present a series of proposed changes to management practices. A total of 194 submissions representing the views of 1290 individuals was received on the discussion paper with the majority of respondents supporting increased protection of aquatic resources (ACT Parks and Conservation Service 1996).

Representatives from Environment ACT (WR&M; ACT Parks and Conservation Service) maintain regular contact with officers from Planning and Land Management in the Department of Urban Services, fishing clubs and the ACT Sport and Recreational Fishing Council to raise awareness of issues involving fish communities.

A number of land management practices have the capacity to adversely affect fish populations, especially urban development, agricultural pursuits and forestry operations. These can generate soil erosion which leads to habitat destruction and deterioration in water quality. Environment ACT representation on appropriate intra- and interdepartmental committees and working groups will continue to provide opportunities for liaison on these matters.

  • Environment ACT will encourage community groups such as fishing clubs and the Australia New Guinea Fishes Association (ANGFA) to assist in the conservation of ACT fish populations and their habitats. Anglers will be encouraged to report any catches of threatened fish.

Implementation, Evaluation and Review


Environment ACT (WR&M; ACT Parks and Conservation Service; Environment Planning and Legislation) have responsibility for coordinating implementation of this Action Plan. Implementation itself, will be a collaborative exercise between government agencies, land-holders and the community generally. NSW participation will be critical in some situations.

Specific actions on Territory Land will be subject to the availability of Government resources. Primary responsibility for conservation and management of the species on Territory Land will rest with Environment ACT.


The Flora and Fauna Committee will review implementation of this Action Plan after three years. The review will comprise an assessment of progress using the following performance indicators:

  • completion of commitments that can reasonably be expected to be finalised within the review timeframe (e.g. introduction of a statutory protection measure for a species; development of a management plan);
  • completion of a stage in a process with a time line that exceeds the review period (e.g. design or commencement of a research program);
  • commencement of a particular commitment that is of a continuing nature (e.g. design or commencement of a monitoring program for population abundance); and
  • achievement of conservation objectives of the Action Plan.

The review will provide an opportunity for both the Flora and Fauna Committee and Environment ACT to assess progress, take account of developments in nature conservation knowledge, policy and administration, and review directions and priorities for future conservation action.

The following conservation actions will be given priority attention:

  • establishment of a monitoring program to allow the detection of trends in relative population size at a number of sites; and
  • subject to resources, commencement of a research program, especially on priority topics, and encouragement of research by others.


Access to unpublished information was provided by Mark Lintermans, Senior Aquatic Ecologist, Environment ACT.

The illustration of the species (Figure 1) was provided by the Murray-Darling Basin Commission.


ACT Government, 2000. Fish Stocking Plan for the Australian Capital Territory 2001-2005. Environment ACT, Canberra.

ACT Parks and Conservation Service, 1995.
A review of recreational fishing in the ACT. Public Discussion Paper, ACT Parks and Conservation Service, Canberra.

ACT Parks and Conservation Service, 1996. Recreational fishing in the ACT: Summary of public responses to a discussion paper. ACT Parks and Conservation Service, Canberra.

Allan, G. and Rowland, S. J. 1992. Development of an experimental diet for silver perch (Bidyanus bidyanus). Austasia Aquaculture 6(3): 39-40.

Barlow, C. C., McLoughlin, R. and Bock, K. 1987. Complementary feeding habits of golden perch Macquaria ambigua (Richardson)(Percichthyidae) and silver perch Bidyanus bidyanus (Mitchell)(Teraponidae) in farm dams. Proceedings of the Linnaean Society of New South Wales 109: 143-152.

Burchmore, J. J. & Battaglene, S., 1990. Introduced fishes in Lake Burrinjuck, New South Wales, Australia. In Pollard D., (ed.) Introduced and translocated fishes and their ecological effects, p. 114. Australian Society for Fish Biology Workshop.Bureau of Rural Resources Proceedings No. 8, Australian Government Publishing Service, Canberra.

Cadwallader, P. L., 1978. Some causes of the decline in range and abundance of native fish in the Murray-Darling River system. Proceedings of the Royal Society of Victoria 90: 211-224.

Cadwallader, P. L., Backhouse, G. N., Beumer, J. P. & Jackson, P. D., 1984. The conservation status of native freshwater fish of Victoria. Victorian Naturalist
101(3): 112-114.

Clunie, P. and Koehn, J. 2001a. Silver Perch: A Recovery Plan. Final Report for Natural Resource Management Strategy Project R7002 to the Murray Darling Basin Commission.

Clunie, P. and Koehn, J. 2001b. Silver Perch: A Resource Document. Final Report for Natural Resource Management Strategy Project R7002 to the Murray Darling Basin Commission.

Dove, A. D. M., Cribb, T. H., Mockler, S. P. & Lintermans, M., 1997. The Asian Fish Tapeworm, Bothriocephalus acheilognathi, in Australian freshwater fishes. Marine and Freshwater Research 48: 181-183.

Gehrke, P. C. 1990. Clinotactic responses of larval silver perch (Bidyanus bidyanus) and golden perch (Macquaria ambigua) to simulated environmental gradients. Australian Journal of Marine and Freshwater Research 41: 523-528.

Greenham, P., 1981. Murrumbidgee River aquatic ecology study. Report to the National Capital Development Commission and the Department of the Capital Territory, Canberra.

Guo, R., Mather, P. and Capra, M. F. 1995. Salinity tolerance and osmoregulation in silver perch Bidyanus bidyanus Mitchell (Teraponidae) an endemic Australian freshwater teleost. Marine and Freshwater Research 46: 947-952.

Hancock, D. A., (ed.) 1993. Sustainable fisheries through sustaining fish habitat. Australian Society for Fish Biology Workshop, Victor Harbor, South Australia, 12-13 August. Bureau of Resource Sciences Proceedings, AGPS, Canberra.

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List of Action Plans - May 2003

In accordance with Section 23 of the Nature Conservation Act 1980, the following Action Plans have been prepared by the Conservator of Flora and Fauna:

No. 1: Natural Temperate Grassland - an endangered ecological community.

No. 2: Striped Legless Lizard (Delma impar) - a vulnerable species.

No. 3: Eastern Lined Earless Dragon (Tympanocryptis lineata pinguicolla) - an endangered species.

No. 4: A leek orchid (Prasophyllum petilum)- an endangered species.

No. 5: A subalpine herb (Gentiana baeuerlenii) - an endangered species.

No. 6: Corroboree Frog (Pseudophryne corroboree) - a vulnerable species.

No. 7: Golden Sun Moth (Synemon plana) - an endangered species.

No. 8: Button Wrinklewort (Rutidosis leptorrhynchoides) - an endangered species.

No. 9: Small Purple Pea (Swainsona recta) - an endangered species.

No. 10: Yellow Box-Red Gum Grassy Woodland - an endangered ecological community.

No 11: Two-spined Blackfish (Gadopsis bispinosus) - a vulnerable species.

No. 12: Trout Cod (Maccullochella macquariensis) - an endangered species.

No. 13: Macquarie Perch (Macquaria australasica) - an endangered species.

No. 14: Murray River Crayfish (Euastacus armatus) - a vulnerable species.

No. 15: Hooded Robin (Melanodryas cucullata) - a vulnerable species.

No. 16: Swift Parrot (Lathamus discolor) - a vulnerable species.

No. 17: Superb Parrot (Polytelis swainsonii) - a vulnerable species.

No. 18: Brown Treecreeper (Climacteris picumnus) - a vulnerable species.

No. 19: Painted Honeyeater (Grantiella picta) - a vulnerable species.

No. 20: Regent Honeyeater (Xanthomyza phrygia) - an endangered species.

No. 21: Perunga Grasshopper (Perunga ochracea) - a vulnerable species.

No. 22: Brush-tailed Rock-wallaby (Petrogale penicillata) - an endangered species.

No. 23: Smoky Mouse (Pseudomys fumeus)  - an endangered species.

No. 24: Tuggeranong Lignum (Muehlenbeckia tuggeranong) - an endangered species.

No. 25: Ginninderra Peppercress (Lepidium ginninderrense - an endangered species.

No. 26: Silver Perch (Bidyanus bidyanus) - an endangered species.


Further information on this Action Plan or other threatened species and ecological communities can be obtained from:

Environment ACT (Wildlife Research and Monitoring)
Phone: (02) 6207 2126
Fax: (02) 6207 2122

This document should be cited as:

ACT Government, 2003. Silver Perch (Bidyanus bidyanus)—an endangered species. Action Plan No. 26. Environment ACT, Canberra.