Southern Pygmy Perch

Scientific name

Nannoperca australisHow to identify a Southern Pygmy Perch

Characteristics

The Southern Pygmy Perch are distinguished by:

  1. Small mouth reaching to just below the eye
  2. Colour is variable but base colour ranges from pale-cream to green-brown, paler on the belly with dark blotches along the body
  3. Breeding males display brighter colours with dorsal and anal fins becoming bright red with black edges
  4. A single, deeply notched dorsal fin
  5. Squarish to slighly-rounded tail

Size

Southern Pygmy Perch are small fish, growing to approximately 65-85 mm in length.

Species similar in appearance

Nil

Distribution

Southern Pygmy Perch formerly found in the Murray and lower Murrumbidgee River systems. There have been large-scale reductions in their range since European settlement, particularly inland. Populations of Southern Pygmy Perch have recently been discovered in tributaries of the upper Lachlan and upper Murray River catchments.


Habitat

Often found in small systems with a low flow rate and quiet vegetated areas in streams, billabongs, lakes and even irrigation channels.  Not usually found in open water, prefers covered habitats.

Southern Pygmy Perch habitat in the Murray River

Why is the Southern Pygmy Perch threatened?

  • Habitat degradation including the loss of riverbank vegetation
  • Removal or modification of floodplain wetland habitat due to flood mitigation works such as levees and wetland drainage
  • Dams alter natural river flow and temperature which leads to the drying and fragmentation of wetland habitat.
  • Competition with and predation by introduced fish, particularly Redfin Perch and Eastern Gambusia

Southern Pygmy Perch males in spawning colours (Photo: L. Pearce)

More information

Watch a video on the Southern Pygmy Perch in the Lachlan River catchment (5:17 mins)


Watch a YouTube video on Southern Pygmy Perch (2:45 mins)