Macquarie Perch

Macquarie perch are medium-sized fish, commonly 30–40 cm and 1.0–1.5 kg. Maximum size is about 2.5 kg and 50 cm. The body is elongated, deep, and laterally compressed. The caudal fin, anal fin and soft dorsal fin are rounded. Spiny dorsal fin medium height and strong. Mouth and eyes are relatively small. Colouration can vary from tan to (more commonly) dark purplish-grey to black. The irises of the eyes are distinctly silver. Macquarie perch are a relatively placid native fish species with the bulk of their diet consisting of aquatic invertebrates such as caddisfly, stonefly and mayfly species, with a small quantity of terrestrial insects taken as well.

Macquarie perch were originally found in the larger upland rivers and streams in the south-eastern corner of the Murray-Darling system, which they usually co-inhabited with trout cod and one or both of the blackfish species. Macquarie perch continue a pattern found in native freshwater fish of the Murray-Darling system of specialisation into lowland and upland stream inhabitants. Macquarie perch are a speciated, more specialised upland version of the golden perch, which is primarily a lowland fish. (Having said this, the primarily lowland golden perch, being highly adaptable species, did extend into upland habitats) in some situations. Macquarie perch are found in the eastern coastal Shoalhaven and Hawkesbury-Nepean river systems as well as the Murray-Darling Basin, indicating that, as with some other native fish genera in south-eastern Australia, Macquarie perch have managed to cross the Great Dividing Range through natural river capture/connection events. …