It's not unusual for kangaroos and wallabies to swim, especially if they are being chased by another animal, such as a dog or dingo.
In 2020, a wallaby was rescued 6.2 kilometres off the coast of North Stradbroke Island in Queensland.
Now I feel slightly less stupid for initially mistaking the headline as 100km offshore! 😅
You probably lost him in the first km or 2, little guy, no need to go 6.