FLIPPER tracks up the shore and a sandy mound were the first signs nesting turtles had returned to the region's beaches.

Mackay and District Turtle Watch spokeswoman Fay Griffin said the first female flatback sea turtle had swum in on the evening tide near Seaforth on Wednesday night, dug her nest and then disappeared back into the sea.

While the arrival of turtles in mid-October was a little early, Ms Griffin said it was not unheard of.

The annual nesting season represented a phenomenal natural cycle, Ms Griffin said, with female turtles hatched on Mackay beaches returning to beaches in the same area decades later.

But each turtle's return to her birthplace was not without its dangers.

Ms Griffin said she was anxious to avoid the tragedy of last year's turtle season, when a flatback turtle was found dead at North Harbour Beach after being attacked by dogs.

To avoid the same incident repeating this year, she reminded residents to keep their dogs on a leash on the beach, especially at night.

Since they were a protected species, Ms Griffin said no one should disturb the turtles or their nests.

Even shining a light at the turtles can have a severe environmental impact, she warned.

"Because quite often that will distract the turtle and she might turn back around and go to the water," she said.

"Allow the turtles to dig her nest, lay her eggs and return to the sea".

If anyone is interested in volunteering with the Mackay and District Turtle Watch Association or spots a potential turtle nest, they should phone 4954 9613.