Biosecurity Spotters logo

Redfin perch (Perca fluviatilis)

Perch were introduced to Australia from the UK in 1868 for hunting, angling and sport. In the Murray-Darling Basin in South Australia, they are considered a threat to native fish species.

Key facts

Type: Pest animal, fish.

Native to: Eurasia.

Established in: NSW, ACT, VIC, TAS, SA.

Other names: Eurasian perch, European perch.

Identification

  • The back is usually bright green to olive, with seven tapering bars extending down the sides.
  • The sides are yellow to yellow-green and the underside is grey to white; colours can vary with habitat.
  • The first dorsal fin has a prominent spine, often black, and parts of the membrane between its spines are blackish.
  • The body feels rough and has 51–61 scales along the lateral line.
  • Adults can reach 51 cm long and 4.75 kg; average length and weight are 35 cm and 1.20 kg.

Where it lives

Perch occur in slow-flowing rivers, deep lakes and ponds, and can also live in brackish water.

Why it matters

  • Several countries have reported adverse ecological impacts following perch introductions.
  • In the Murray-Darling Basin in South Australia, perch are considered a threat to native fish species.
  • Juveniles feed on zooplankton, bottom-dwelling invertebrates and other perch fry; adults feed on invertebrates and fish, including sticklebacks, roach and minnows.

How it spreads

  • Perch were introduced to Australia from the UK in 1868 for hunting, angling and sport.
  • Stocking is identified as a pathway, including stocking perch as a sport fish.
  • Water is a local pathway: perch can swim to new areas within a water body.

Control methods

  • Consult the relevant authority for guidance on managing this species; the datasheet refers readers to ISSG (2011) for management information.
  • When considering chemical control, consult the national list of registered pesticides or relevant authority to determine which products are legally allowed for use.
  • Use any pesticide lawfully and consistently with its product label.

Site hygiene and welfare

  • Water is identified as a local dispersal pathway because perch can swim to new areas within a water body.
  • Use methods set out in the national model codes of practice and standard operating procedures for the species.
  • Coordinate control with neighbours and the local government biosecurity plan, as isolated effort is quickly undone by reinvasion.

Classification by state

  • Australia (national): No national listing. Managed under state and territory law.
  • Queensland: Not prohibited or restricted. Not listed as prohibited or restricted matter in Queensland. Everyone must also take all reasonable and practical steps to minimise its risks (the general biosecurity obligation).
  • New South Wales: Notifiable aquatic pest. It must not be possessed, bought, sold, moved or released in NSW, and you must notify NSW DPIRD within one working day of finding it. The general biosecurity duty applies: anyone dealing with it must prevent, eliminate or minimise the risk it poses.
  • Victoria: Not declared. Not declared under the Catchment and Land Protection Act 1994. Other Victorian laws may still apply.
  • South Australia: Noxious species. Declared a noxious species under the Fisheries Management Act 2007, so it must not be brought into South Australia, kept, sold or released, and it must not be returned to the water alive. Report any sighting to PIRSA FISHWATCH on 1800 065 522.
  • Western Australia: Not listed. Not found in the Western Australian Organism List. Check with DPIRD before moving or keeping it.
  • Tasmania: Not a declared pest. Not a declared pest or prohibited matter in Tasmania. Importing animals is still controlled by Biosecurity Tasmania.
  • Northern Territory: Not a declared pest. Not on an NT declared or prohibited list. Check with the NT Government before keeping, moving or releasing it.
  • Australian Capital Territory: Declared pest, prohibited. It is a declared pest throughout the ACT. Dealing with it, such as selling, moving or keeping it, is prohibited.

Legal obligations

Every state and territory places a duty on landholders and people working on land to prevent the spread of invasive species, such as the general biosecurity obligation in Queensland and the general biosecurity duty in New South Wales. Declarations and control requirements differ between states and local government areas, so check the current official list before work starts.

  • New South Wales: Biosecurity Act 2015 (NSW), administered by NSW Department of Primary Industries and Regional Development
  • Australian Capital Territory: Biosecurity Act 2023 (ACT), administered by ACT Biosecurity
  • Victoria: Catchment and Land Protection Act 1994 (Vic), administered by Agriculture Victoria
  • Tasmania: Biosecurity Act 2019 (Tas), administered by Biosecurity Tasmania
  • South Australia: Landscape South Australia Act 2019 (SA), administered by the regional landscape board

Sources