In Australia, 439 rivers are counted and many are small tributaries with relatively low and variable flows.
Here are top 5 longest rivers in Australia as they play economic, social, ecological, and cultural roles in modern day Australia.
 1. Murray RiverÂ
This is the longest river in Australia with 2,508 km. It stretches from the Australian Alps to the Southern Ocean. Aquafauna present in the river includes Murray cod, perch, catfish, western carp gudgeon, and trout cod.
 2. Murrumbidgee River
The river flows for 1,485 km from the Australian Alps meandering its way to join the Murray River in the riverine plains. The water is home to populations of Murray cod, Murray Cray, perch, crayfish, trout cod, Mountain galaxies, and Australian smelt.
  3. Darling RiverÂ
The river stretches for 1,472 Km from southwest Queensland. The river supports populations of perch, catfish, Murray cod, and Murray hardyhead as well as lizards, frogs, turtles, rats, koalas, and possums.
 4. Lachlan River
The river flows for 1,448 km from near Goulburn in the Great Dividing Range and terminates at the Great Cumbung Swamp near Oxley.
5. Warrego River
The river flows for 1,380 km from the Carnarvon Ranges on the Great Dividing Range in Queensland and flows south where it joins the Darling River upstream of Louth.