Green sea turtle released more than a year after being found with horrific injuries on Great Keppel Island

A vulnerable green sea turtle that washed up with life-threatening injuries on a remote beach has returned to the sea — 18 months, and thousands of dollars worth of food later.

In November 2018, a Great Keppel Island resident raised the alarm after finding Denise with a sliced throat, cut eyelid and half a flipper missing.

In rough seas, rescuers loaded the injured turtle onto a bodyboard and carefully towed her to an accessible beach.

With the help of a forklift, she was ferried 15 kilometres to the mainland and driven another 50km to Rockhampton veterinarian Greg Muir.

During her 18-month recovery at the Quoin Island Turtle Rehabilitation Centre, Denise put on more than 30kg and ate more than $15,000 worth of squid, sardines and pilchards.

Denise's flipper was amputated after a suspected boat strike.(Supplied: Alma Street Veterinary Hospital)

Manager Kim van Oudheusden said Denise would not have survived without the help from so many people.

"Her flipper was half chopped off and a boat had sliced her throat and her eye lid had been chopped off," she said.

"The vet kept her overnight and stitched that back up and then she came here in a car and then we took her on a boat here — it was quite an operation.

"We are so grateful to all those people that help us out and do these amazing things because without them, we would not be able to rescue these turtles."

She was named after one her rescuers, Denise Weisse, president of the Keppel Turtle Fund Inc.

Carers at Quoin Island have rescued and rehabilitated hundreds of turtles since 2011 but owner Bob McCosker developed a strong bond with Denise during her lengthy stay.

"I'm happy to see her extremely healthy like she is, but sad to have to see her go through her life flipperless, thanks to another boat," he said.

"I laid down beside her and while I was pulling her stitches out of her eyes, she did not move, didn't flinch — she just watched me and she knew what we were doing.

"They are amazing animals."

Breeding the next generation

Marine biologist Liam Turner and his partner Hayley Coen have been caretakers at the centre for six months.

"It's a really good feeling to release a breeding female out into the wild," Mr Turner said.

It takes females of the vulnerable species' 30 to 40 years to reach reproductive maturity.

"Once she's in the water she's fine, but obviously they don't navigate the land too well with only the one [front] flipper," Mr McCosker said.

"It's just going to be difficult for her to find her way up a beach and lay [eggs].

"But they're an amazingly resilient animal and they just never give up."