Dan originally tagged and released the fish on July 17, 2019, the NSW Department of Primary Industries said on Facebook.

He caught and released it on October 14 that year, before doing so again on June 8 this year, all in Lake Macquarie in NSW's Hunter region.

"Talk about deja vu!" the post said.

The flathead was also caught and released by Stephen Ireland on April 13 last year.

The fish was tagged three months before Dan's original catch.

"It has now been caught an incredible four times within the space of two years. Overall, the fish has spent 693 days at liberty and grown two centimetres in length. On each occasion, the fish was recaptured within 500m of the original release point," the post said.

"This shows that mature dusky flathead display a degree of 'philopatry', which is when an animal has a tendency to stay in an area or habitually return to the same location."

READ MORE:

The department said the story reinforced that "the humble flatty is a resilient species, well suited to catch and release fishing".

"Provided they are handled with care and released quickly, flathead can continue to contribute to the fishery."

Tips on correct handling techniques for catch and release fishing are on the department's website.

"Recent research has shown that most fish survive using current catch and release techniques, with the main factors found to reduce survival being deep hooking and poor handling," the website said.

Dusky flathead had a 91 to 96 per cent survival rate after being caught and released.

The survival rates of other fish in these circumstances include: luderick (99 per cent), mulloway (73 to 81 per cent), sand whiting (93 per cent), snapper (67 to 92 per cent), yellowfin bream (72-97 per cent) and tailor (92 per cent).

The catch and release technique was "quite common for fishers with a strong conservation commitment to release fish that they could legally keep" .

"Compliance with bag and size limits and various fishing closures also means many anglers, by law, return fish they have caught to the water."

Wonder if the big dusky will end up on someone's dinner plate one day, or swim happily in the lake for years to come?

Apparently they can live for up to 20 years.