We're talking the NSW Game Fishing Association's State Championships, of course, better known as Interclub.

A time-honoured battle for prestige with GFA clubs throughout NSW coming to Port Stephens, the home of gamefishing in Australia, to compete across a range of divisions for the mantle "best of the best".

The first ever black marlin caught in Australian waters was landed by Dr Mark Lidwell back in 1913 and that fish remains on display in Sydney's Maritime Museum to this day. Adding to the pedigree, host club Newcastle and Port Stephens GFC celebrated its 90h anniversary last year.

There is much honour and prestige involved, and good reason to be optimistic about the fishing after last weekend's Garmin Billfish Shootout produced 146 marlin, 107 of which were stripes (the rest, 30 blues and nine blacks).

"The fishing is going to be hot this weekend," NPSGFC secretary Nigel Rushworth said.

"Last week there were great numbers of pelagics tagged and that's continued through the week. Yesterday [Wednesday] there was a report one boat tagged 14 stripes. It's been years since we've had such a run and it's going to be great."

Organisers of the Shootout were vindicated in their decision to stare down the weather gods and proceed with the tournament after some serious weather through the week.

Apart from a few interesting moments on the bar last Saturday, conditions were perfect for fishing, if not a bit rolling.

"There was a fair bit of dirty water coming out of the bay and other outlets but there was a stack of fish out on the Shelf and heaps of fish raised," Nigel said.

The big money prize of $200,000 for biggest marlin over 268kg did not go off, nor the $12.5k for biggest shark, but Port Hacking boat The Cuban pocketed a cool $12.5k for heaviest marlin over 150kg, a 157kg blue.

Port Hacking boat Zorro won champion boat tag and release with 103,500 points.

Among a host of great hook-ups, anglers aboard Tim Dean's Calypso nailed a marlin grandslam (tagged a black, blue and striped)

Interclub fishing gets underway this morning following the traditional sail past, followed by three frenetic days of fishing. Approximately 30 boats contested the Lyndy Grieves Memorial Ladies Day tournament on Thursday.

As always with Interclub the focus will be on tag and release, with members of the scientific community on hand to make the most of the few fish that are weighed.

"Those scientists will include Dr Julian Pepperell, a renowned marlin research specialist who was recently inducted into the International Game Fishing Assocation Hall of Fame," Nigel said.

Shark Researcher Nick Ottway, from DPI, will also attend, as he has for the last decade and a half. Researchers will also look into the eyesight of marlin, and the parasitology of sharks,

North Rothbury angler Ben Hall has had a big week in the wake of posting a pic of what looked like a Japanese sea bass caught in the Hunter River last week.

Lured down from North Rothbury by chance of catching a mulloway after the rain, he duely pulled in a fish which his mate immediately noted was a bit different.

One thing led to another after he posted pics on Facebook and it seems DPI and the Australian Museum are all but convinced, pending official DNA testing in the next two weeks, that it is a Japanese sea bass.

"DPI collected a fin clipping on Monday and the Australian Museum contacted me wanting a soft tissue sample so they can ID the fish," Ben said this week.

Renowned fish researcher Dr Julian Pepperell, who is down in Nelson Bay this weekend for Interclub, is pretty sure it is a Japanesee sea bass and is excited.

"They are pretty rare in our waters - the last two fish were caught in the 1980s in Broken Bay and Botany Bay and they were nowhere near as big as this one," he said.

Indeed, Ben did some research and believes the official world record for a Japanese sea bass caught on 20lb line is 17lb and his fish went 27lb, but he's not going to chase that up.

Dr Pepperell said it's likely the fish arrived here via ballast water from a cargo ship and that Ben did the right thing from a scientific point of view keeping the fish, even though there was robust debate on social media to the contrary.

"It's in freezer at moment," Ben said. "I'm going to get it mounted and when that's done I'll donate the frame to the museum. In the meantime, I'll just ride the fame."

The big flush of fresh water has sparked up local estuaries with reports of a wide range of fish being caught, including kingfish, flathead and mulloway.