They're cute. They're native Australians. They inhabit our most iconic river. They're endangered by an introduced and voracious pest. And November is "Turtle Month", the most crucial time in their reproduction cycle.

Most Australians associate turtles with the ocean, not realising their shy, freshwater cousins (about 30 species) are hiding in rivers, lakes and farm dams all over the country – just about anywhere where there's freshwater (except Tasmania).

A Murray River turtle – the species is threatened by feral predators and poor water quality. Credit:Graham Stockfeld

However the three species commonly spread throughout the Murray-Darling Basin – the Murray short-necked, the eastern long-necked and the broad-shelled turtles – are under serious threat from feral predators, poor water quality and (strangely) road accidents.

Research scientist Ricky Spencer, of Western Sydney University, is the leader of a project to monitor turtle numbers in the Murray River, from the Snowy Mountains to the Great Australian Bight.