The engines rumbled to life in the predawn dark on Thursday, more than 30 sport boats headed offshore to launch the oldest billfishing event in the state, the 46th annual Blue Marlin Tournament in Georgetown.

The first casts were the beginning of the annual South Carolina Governor’s Cup Billfishing Series, this year a five-tournament competition that is the signal flag on the lines of a recreational fishing industry said to bring $600 million per year to the coastal economy.

Their boats are top of the line. They pay thousands of dollars each to enter different categories in the tournament, thousands more to get into pools of extra cash awards and hundreds of dollars each run in fuel alone.

But these anglers bring something bigger to the table: the future of fishing off the Lowcountry coast. And many of them don’t even realize how important they are.

When the boats pull back to the docks, state wildlife officers are waiting to record what they caught, where they caught it, the bait and hooks they used and other details.

The information goes into a database that has been compiled for more than 30 years. It’s the only detailed catch history of its kind in the East if not the country.

Meanwhile, from that record the S.C. Department of Natural Resources has expanded to track meat fish such as tuna, wahoo and dolphin fish, as well as billfish caught year-round.

So, the database has become an unrivaled, sought-after resource for tracking a lot of popular offshore fish — pivotal to state, federal and now international fishery managers such as the International Commission for the Conservation of Atlantic Tunas trying to save the prized, disappearing food fish. The DNR tracking may well end up being the thing that keeps sought-after fish in the ocean off the Lowcountry, and keeps anglers like the tournament competitors coming after them.

“South Carolina has the best data set for its offshore fisheries. Period,” said fishing researcher Don Hammond. He ought to know. It was his idea more than 30 years ago. Today, he’s about to incorporate the dolphin fish data into his research for Cooperative Science Services, his company.

‘Unit of effort’

Those pricey sports boats in the billfish series are the new faces in a centuries-old lineage of ketches, schooners, sidewheelers and the like that are the heritage of the Lowcountry. Theirs is the coast that used to be defined by commercial fishing and shrimping.

Both industries have been strangled by tighter catch restrictions on the fish they’re after, fish that regulators say are caught too often to sustain the population. The commercial boats have disappeared one by one. Meanwhile, more than 80,000 South Carolina residents hold saltwater fishing licenses, a number that does not include out-of-state license owners and some tourist anglers. More than 2 million recreational trips per year are run offshore.

The DNR needs the data it compiles to keep the whole works afloat. The data is far richer than a simple record of catch numbers, it’s an equation of catches based on “unit of effort,” how many hooks in the water for how long. It’s comprehensive to the point of factoring in times when the other lines on a boat are pulled out while a big catch is wrestled in.

If all the tournaments were doing that, and had been doing it, stock assessments would be far more accurate, said Wally Jenkins, who coordinates the billfish series and the data records for DNR.

As just one example, the billfish boats last year caught a total 32 white marlin, one of the species regulators are worried about. But, “that’s a pretty decent number for something that’s supposed to be endangered,” Jenkins said.

Catch and release

The day before the Blue Marlin Tournament opened, Jim Johnston was aboard Big Sky, fitting out the boat he traded his Montana retirement for.

Johnston, 68, has fished in the tournament for every one of its 46 years. He used to own the Georgetown Landing Marina where it’s held. If there’s a rival to DNR’s record history, it’s him. He can reel off the number of boats that competed and the fish caught in the early years. He can talk sizes and strategies.

“I almost know it by heart,” he kidded. Yet, “I don’t know that anybody other than DNR is as aware of it as I am.”

Most anglers, though, have come to expect the DNR officers as soon as they hit the dock. It’s one more formality that makes for the event’s import and pageantry. Everybody knows what’s at stake. The series stresses catch and release, and touts that some nine of every 10 fish hooked are put back.

And coincidentally enough, billfish catch numbers have climbed dramatically for nearly a decade after holding steady for years, while meatfish numbers keep tanking. You can’t attribute that to the tournament’s catch-and-release, but it’s a nice affirmation. The catch records are “really a pioneer state program focused on benefiting recreational fishermen,” Hammond said. “It’s something we can take pride in.”

Reach Bo Petersen at 937-5744, @bopete on Twitter or Bo Petersen Reporting on Facebook.