Why are dead fish hanging from rural road signs?

For more than a decade, it's been a mystery that's perplexed people driving the lonely roads of regional Queensland.

All the fish are dried out, shrivelled by the elements. Some are filleted. Some are not.

Is it to warning to would-be anglers? Or a welcome?

Research indicates the strange phenomenon began at least a decade ago in north Queensland, but recent social media activity indicates the practice is spreading throughout the rest of the state.

Central Queensland angler Clayton Offord, who lives 50km south-west of Rockhampton, has been doing this for five years and provides the answer.

"We just hang it up for everyone to see and for everyone who drives past to have a look," Mr Offord said.

His latest offering was the desiccated carcase of a 30kg, 1.4-metre Silver Jew, which hangs on a road sign pointing to his property off the quiet South Ulam Road.

And it has the district talking.

"I'm a legend at the pub," Mr Offord said.

"Every time I walk in the pub they rave on about it.

"I know a lot of people who go fishing and they catch nothing, and me and young fella just put it up for everyone to see, mate."

The fish-hanging trend can be found nearby in Upper Ulam, towards the Capricorn Coast at Cawarral and south to Gladstone.

"They all do it," Mr Offord said.

Clayton Offord landed this 30kg, 1.4m Silver Jew at Port Alma. ( Supplied: Clayton Offord )

The Silver Jew, accompanied by a more modest-sized coral trout, put up a fight when it was caught nearby at Port Alma, a popular fishing spot between Rockhampton and Gladstone.

"I fought it for 15 minutes and I thought it was a big shovel-nosed shark, so I handed it to me young fella, Sam. He's 17, and he fought it for another 15 minutes," Mr Offord said.

"And then we seen it come up the side of the boat and I would have had it in about two seconds with a gaff in it," he said.

Before hanging up the carcase, Mr Offord managed to collect about 17kg of flesh from the fish.

"It's really good eating," he said.

Apparently catching fish this size was not out of the ordinary for Mr Offord; the fourth-generation Bajool resident has fished since he was five, and caught a fish this size only four months ago.

"They call me the fish whisperer," he laughed, pointing to his shirt with that very name printed on it.

Mr Offord's son Sam has a similar reputation.

"He could catch a fish out of a toilet bowl!" Mr Offord said.

Although hanging fish carcases from road signs is a slight case of bragging, there is another reason.

This particular fish was to show that controversial net-free fishing laws introduced last November had an impact on the local fish stocks, Mr Offord said.

"We have a lot of friends who live along here, and it's just to show them that ever since the netting laws changed, mate, that there are fish like this out there. It's unreal."

"There are a lot of porpoises, and turtles that have come back in the numbers — they're unbelievable.

"There's more bait, more fish, more birdlife, and the number of fish has really picked up."

Meanwhile, Mr Offord said his secret to fishing success came down to one simple factor: passion.

"It's the love of fishing and it's something we've always done, even when we were tackers with the old fella, with Dad, we'd always go fishing. I would do it for a living if I could."