And winkling them out is the task facing PhD researcher Dr Peter Macreadie, of University of Technology Sydney.

Dr Macreadie is a core member of the UTS Plant Functional Biology and Climate Change Cluster.

"It is extremely rare for any animal to stay in one spot for long but razor clams, if and when they settle, stay in exactly the same place for up to 20 years and that gives us a potentially detailed historical record of the ecology of its immediate environment and biological data," Dr Macreadie said.

"Even the empty shells, long buried after the animal has died, can hold records dating back thousands of years."

Dr Macreadie has been researching seagrass conditions and development in Lake Macquarie since 2010 but in the last six months has focused on razor clams.

"So little is known about these creatures. They arrive as spawn carried by currents but their mortality rate in the early stages is horrific.

"If they survive they might flourish as a population and then suddenly disappear only to reappear many years later," he said.

Dr Macreadie is using sophisticated technology, including nuclear science, to unlock the mysteries held by the razor clams.

"They are a bit like trees except that counting and analysing the rings is very complex," he said.

Friend or foe irrespective, the bi-valve razor clams are believed to be an important if as yet unidentified part of the lake's ecological chain.

"I believe they are native creatures though they are common all over the world and I'd say there are no more of them in the lake now than there's ever been, they are just being noticed more though it is possible that improved seagrasses are helping the clam populations survive as they love seagrass areas," Dr Macreadie said.

"It is unlikely that the bi-valve clams have much beneficial filtration effect on the water quality as seagrass excels at that and clam numbers simply can't compete with seagrass in that context.

"I also doubt that professional fishermen had much of an effect on the past clam population.

"The clams that are considered a danger are in shallow water where most fishermen didn't operate but all the pointers indicate that the clams do play an important role.

"We shouldn't eradicate them, just clear specific swimming areas using existing bag limits," he said.

The first scientific data results are available in about six months.