A canine castaway lost at sea has been reunited with her owners after spending more than four months living off goats on a Queensland island.

Owner Jan Griffith said her family were devastated when their cattle dog, Sophie Tucker, fell off the side of their boat in choppy waters off the Mackay coast in north Queensland in late November.

But unbeknown to them, their hardy hound swam five nautical miles to St Bees Island, where she survived until last week by hunting baby goats.

She was last week returned to her family after rangers captured what they believed was a wild dog.

Ms Griffith said she and her husband had contacted rangers after friends suggested the dog – who had earned a name for herself on the island – might be their long-lost pet.

Last Tuesday the couple met the rangers’ boat as it ferried the dog back to the mainland and were blown away to find Sophie Tucker on board.

“We called the dog and she started whimpering and banging the cage and they let her out and she just about flattened us,” Ms Griffith said.

“She wriggled around like a mad thing.”

But even more unbelievable was hearing how their domesticated “inside” dog had survived, she said.

“She had looked really poor (on the island), the story was, and then all of a sudden she started to look good and it was when the rangers had found baby goat carcases so she’d started eating baby goats,” she said.

“We think she’d swum close to five nautical miles from the boat where she went in and then some people believe she went backwards and forwards from Keswick to St Bees (islands).”

Ms Griffith said their pet had been quick to embrace her now easier existence – complete with air conditioning.

AAP