The unnamed man was left stranded on Townshend Island, off the coast of Queensland, for three days after the crocodile sank its teeth into his boat.
He told authorities he fended off the animal before paddling to the island, where he stayed for three days.
He was rescued by helicopter on 6 August after activating a locator beacon.
"He was very fortunate," a spokeswoman for the Australian Maritime Safety Authority told AFP.
"It didn't pierce the kayak. He said he was running on adrenaline [to get to the island]."
The man was prevented from leaving the island by bad weather and a low tide. He activated his rescue beacon after running out of provisions.
Saltwater crocodiles are the world's largest living reptiles. They have become more common in Australia since becoming a protected species in 1971.
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The eight-week-old Labrador and 10-week-old Malinois have been bred in Scotland specifically for police work and are already showing skills.
PC Gareth Wedley, who is Luna's handler, said the Labrador was chasing and fetching a ball earlier than any puppy he had seen at her age before.
The pair have joined the 17 other dogs in the force's dog section.
Luna the Labrador - named after a character in the Harry Potter books - is living with PC Wedley and his other working dog, a two-year-old general purpose dog called Axe.
"Luna is doing really well at the moment - she's already displaying a desire to chase and find a ball and bring it back to me, when she wants to give it back that is," he said.
"This is something which I haven't seen in a puppy I've had of her age before.
"She's currently undergoing some training and we are also trying to introduce her to various environments.
"Early socialisation and introducing the dog to a wide range of people, animals and experiences is essential to ensure a sociable, well-adjusted and balanced dog which is suitable for police work."
Diesel, who has been living with handler PC Sonia Stobbart for the past two weeks, was named after the police dog who died during the recent terror attacks in Paris.
"Having another puppy is hard work, there's plenty of sleepless nights and hours of your own time spent with them," she added.
"It's all worth it to know that you have a dog that you have put everything into yourself because I will spend the next eight years working with him, he will be my protector and best friend."
A man whose kayak was attacked by a saltwater crocodile has been rescued from an island in Australia.
[NEXT_CONCEPT]
North Wales Police has recruited two keen and eager new members - crime-fighting puppies Luna and Diesel.