MRWN spokeswoman Fiona Corke said in recent weeks volunteers had been made aware of an increasing number of animals being left to suffer after being hit by cars on roads in the shire.

These include recent incidents of two koalas left injured on the road, several kangaroos, two echidnas, magpies, wombats and a female wallaby, who was pregnant with a rare set of triplets.

Ms Corke said motorists were legally obliged to render assistance to an injured animal by reporting it to relevant organisations.

"It is so disheartening to find these poor animals just left, still alive and suffering with missing or broken limbs and bones sticking out, writhing in agony in the cold. Joeys are found dead and rotting in a live suffering mother's pouch, who are also at risk of being pulled apart by a dog or fox."

A Gisborne resident, who did not want to be named, said on July 13 she stopped to help a healthy female koala cross Gisborne Melton Road, but was horrified that motorists failed to slow down or stop.

"The cars didn't slow down, no one stopped to help, then a car hit the koala, it flew up into the air, then hit the road hard. I can't get it [out] of my mind, it was just horrific."

Ms Corke said an increase in commuters in the shire had led to an increase in the number of wildlife being hit by motorists.

"People are driving to and from work in the dark, the time wildlife is most active, so please take care driving at these times, concentrate and use your peripheral vision, many people have lived up here all their lives and never hit anything, it's all to do with how you drive."

To report injured wildlife, call Wildlife Victoria's emergency rescue line, 1300094535 or RACV, 131111.