Murray Hardyhead

Interesting Info

• The Murray Hardyhead is endemic to the Murray–Darling Basin, once widespread across Victoria, South Australia, and New South Wales, but now surviving only in a few isolated wetlands and saline lakes.
• Its body is slender and semi-transparent with a faint golden-green shimmer along the sides, and a dark stripe is sometimes visible from snout to tail.
• Their diet includes zooplankton, insect larvae, micro-crustaceans, and algae, making them grazers of the lower food chain and prey for larger fish and waterbirds.
• They often form shoals of dozens to hundreds, which flash silver as they dart in unison in shallow water.
• The Murray Hardyhead is a tough survivor, it can live in water that is highly saline, low in oxygen, and subject to sudden changes — conditions that kill many other native fish.
• Despite this toughness, it is highly vulnerable to loss of habitat, especially when wetlands are drained, regulated, or invaded by carp and mosquito fish.
• Breeding occurs in spring and early summer (October–December) when water warms. Females scatter adhesive eggs onto aquatic plants or algae, and the larvae hatch in about a week.
• Like other hardyheads, they can spawn multiple times per season, boosting their chances of survival when habitats shrink.
• The lifespan is very short, usually 1–2 years, which suits their boom-and-bust habitats.