The southern Riverina has been labelled as one of the hot spots for the plague during late spring to summer with growers urged to check their crops now and start baiting if they notice any damage.

The Department of Primary Industries (DPI) has reported crop damage is low, but there have been cases of isolated crop damage in the Riverina's south in canola and cereal crops towards the edges of paddocks.

DPI director of invasive species John Tracey said if farmers don't start preparing themselves now crop damage will increase significantly.

"Ideal seasonal conditions and a large carry-over population from autumn point to a continuation of Australia's worst mouse plague in living memory," Mr Tracey said.

"With the start of spring, we're encouraging farmers to walk through their crops and check for mice activity and start planning control measures and baiting.

The DPI has reminded farmers to only use registered baits following an increase in the number of illegal or homemade baits.