It is a life cycle in which they hatch and metamorphose through four different stages of life, from eggs to adult. But while the broad outline of this remarkable story is known, the eels' life cycle is still shrouded in mystery.

This is what   ecologist Jarod Lyon and his team at the Arthur Rylah Institute will be trying to unravel later this year.

From April, the researchers will be working with traditional owners of south-west Victoria to attach satellite tags to short-finned eels on Gunditjmara country, before the eels embark on their one-way trip to paradise.

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The project will combine knowledge gained from some of the most cutting-edge technology with some of the world's most ancient.

Gunditjmara built a way of life around the migration of the short-finned eel, engineeringtheir country to raise, fatten and trap eels. These eel traps, at more than 6500 years old, are being considered for World Heritage Status.

The scientists hope to tap into that ancient knowledge about the freshwater stage of the eels' lives as they seek answers about their saltwater sojourn.

Much of what is believed about that latter phase is based upon educated guesswork.

Research boats that trawl the Coral Sea have found large numbers of eel larvae, so it is thought the eels' spawning ground is somewhere between New Caledonia and New Guinea.

Elsewhere in the world eels are known to spawn around underwater mountains, so it is presumed the same is true here, but as the spawning grounds haven't been seen they are likely deep underwater.

Long-finned eels live from Cape York to Wilsons Promontory, while the short-fins range from northern NSW to south-western Victoria.

Their migration could be as far as 5000 kilometres and take more than a year – a period of time during which they don't eat. So it's presumed they look pretty shabby when they get to their destination.

"By the time they get there they are probably just backbone and reproductive material," Dr Lyon said.

It is believed both long-finned eels and short-finned head to the same vicinity, but Dr Lyon said they were not spawning with each other "otherwise we'd have medium-finned eels".

The start of their migration ranges from January through April. But what triggers the eels into action is yet another of the unanswered questions.

And as the ocean warms and faces increasing pressure by coastal development, fishing and shipping, the answers will become ever more important. Because while Australian eels appear to be doing okay for now, the same is not true elsewhere such as in Europe.

"If we've got this information beforehand, it's better than waiting for some sort of future crisis before we start looking into it," Dr Lyon said.