A turtle researcher says global warming is behind an influx of loggerhead turtles breeding in south-east Queensland.

Researcher Jennie Truman monitors loggerhead and green turtle nests on beaches at North Stradbroke Island, off Brisbane.

She has seen a big increase in breeding activity on the Island and believes that is due largely to global warming which is making beaches further north too hot for nests.

"The sand temperature has started rising up there and it is cooking the eggs basically and not incubating them," she said.

She says as south-east Queensland is increasingly playing an important part in turtle breeding, local authorities must work with researchers to better accommodate the seasonal influx of the endangered species.

Meanwhile, conservationists on North Stradbroke Island are calling for the community to become plastic bag-free to help protect turtles and other marine life.

This summer residents in south-east Queensland have monitored 16 loggerhead and green turtle nests on the island.

That is a big increase on previous years, and researchers say it could be due to global warming which is making beaches further north too hot to nest.

Stradbroke Island Management Organisation (SIMO) spokeswoman Jackie Cooper says the area is home to endangered creatures and more must be done to protect them.

"A lot of people on the island every morning are walking on the beach - they carry a bag to put rubbish in and they collect rubbish off the beach," she said.

"You never come back with an empty bag - it's always got some rubbish in it.

"For Stradbroke to stand up and say we ban plastic bags gives a message to all our visitors and to the rest of Australia that we care about our marine environment."