A dainty tree frog from Queensland has leaped across Bass Strait to Tasmania inside a packet of bananas, raising serious biosecurity concerns.

Launceston woman Linda Emery made the shock discovery after her usual grocery shop at Coles in Kings Meadows.

"We purchased the bananas with our groceries yesterday [Friday] at one of our local stores," she said.

"We didn't unpack the bananas until today [Saturday] and we found a little green tree frog inside the bag.

"I said [to the frog] 'Oh, what are you doing here? You're meant to be in Queensland!'.

"I knew that it was not one of ours [in Tasmania], even though we have got frogs in our garden.

"I didn't really want to go and release him out in the garden because he was completely different."

Ms Emery put the frog in her fridge to "put it to sleep" and alerted biosecurity.

Efforts have been made to encourage producers to ensure their bananas travel free of frogs. ( Supplied: Ann Jones )

Local frogs at risk from disease

It was a good thing she did not release it outside, according to Kathy Potter from the Frog and Tadpole Study (FATS) Group of NSW.

Ms Potter said she had never heard of a dainty tree frog (litoria gracilenta) being found in Tasmania, where they are not endemic.

"If she [Ms Emery] had put it out in her garden the chances are it would have just died, considering what the temperatures are there," she said.

"But even so, the frog could be carrying a disease that comes from chytrid fungus, a disease that is affecting frogs all over the world.

"And if it was carrying this disease and it was introduced into an area where there was frogs that had not been exposed to this disease all of the frogs in that region could possibly die."

According to Tasmania's Parks and Wildlife, the chytrid fungus occurs in much of the state but the Wilderness World Heritage Area was mostly free of the disease.

Ms Potter said FATS ran a rescue service for "lost frogs" that had ended up in freight and subsequently groceries.

"We have had four calls to pick up specifically litoria gracilenta that have been from Coles bananas in the past two weeks," she said.

Banana producers asked to do checks

According to Parks and Wildlife, "kidnapped" frogs get processed along with the bananas, being washed, sprayed, soaked and packed before being shipped off to Tasmania.

It says such "accidental importation" was not as common as in the past.

Ms Potter said efforts have been made to raise awareness about the problem with banana producers.

"Our organisation has actually contacted some of the people that grow bananas and actually asked them if they could check the hands of bananas before they boxed them," she said.

"It is a shame to euthanise a healthy animal because it hopped on the wrong truck."

Ms Potter said it was extremely important that if people find a lost frog they should not release it back into the wild unless they know exactly where it came from.

Ms Emery said biosecurity would pay her a visit in the coming days to examine the frog.

The Department for Primary Industries has been contacted for comment.