Macquarie Perch

Scientific name

Macquaria australasica

Status in NSW

Endangered.

Characteristics

The Macquarie Perch are an elongated, oval shaped fish. They are distinguished by:

Large eyes
Pores on the snout and around the eye
Jaws of equal size
Large distinct scales along the body
Rounded tail
They can be black, silver-grey, blue-grey or green-brown in colour, with a paler underside

Macquarie Perch from coastal catchments are blotched with grey-brown, buff and dark grey patches over the head and body.

A Murray-Darling Basin form (top) and a coastal (bottom) form Macquarie Perch

Size

Macquarie Perch from the Murray-Darling Basin are larger, growing up to 46 cm and 3.5 kg. Macquarie Perch from coastal catchments are distinctly smaller, usually less than 18 cm in length

Species similar in appearance

Australian Bass.

Distribution

Macquarie Perch are found in the Murray-Darling Basin (particularly upstream reaches) of the Lachlan, Murrumbidgee and Murray rivers, and parts of south-eastern coastal NSW, including the Hawkesbury/Nepean and Shoalhaven catchments.

Habitat

Macquarie Perch occur in waters with lots of cover such as aquatic vegetation, snags, boulders and overhanging banks.

Why is the Macquarie Perch threatened?

The construction of dams, weirs and road crossing creates barriers to fish movement
Dams can discharge cold water which may disrupt temperature cues for spawning
Removal of riparian vegetation increases erosion and siltation, resulting in the loss of deep pool habitat and smothering cobble bed spawning habitat and eggs
Infection of Macquarie Perch by Epizootic Haematopoietic Necrosis Virus (EHNV), which is carried by the introduced species Redfin Perch and farmed Rainbow Trout
Historic overfishing and current illegal fishing practices
Pollution from domestic, agricultural and industrial sources
Extreme weather event, such as drought and bushfires
Competition with and predation by introduced fish, particularly Redfin Perch, European Carp, Brown Trout and Rainbow Trout